ARGX

We take a centralized approach to managing our exposure to market risks globally. We coordinate our access to national and international financial markets and consider and manage continuously the financial risks concerning our activities. These risks relate to the adequacy of our equity and debt capitalization, the creditworthiness of our counterparties, our short-term liquidity, the impact of changes in interest rates on our investments and fluctuations in foreign currency exchange rates. We do not believe that risks relating to interest rates on borrowings are material as the Company has no financial debt. We do not buy or trade financial instruments for speculative purposes. For additional information on risk factors applicable to the Company, its business, financial condition and results of operations, please see “Item 3.D. — Risk Factors.” See “Note 24 — Financial Risk Management’’ to our consolidated financial statements appended in our Annual Report and incorporated by reference herein. Capital risk The Company manages its capital to ensure that it will be able to continue as a going concern. The capital structure of the Company consists of equity attributed to the holders of equity instruments of the Company, such as capital, reserves and accumulated losses as mentioned in the consolidated statements of changes in equity. The Company makes the necessary adjustments in light of changes in the economic circumstances, risks associated to the different assets and the projected cash needs of the current and projected research activities. On December 31, 2025, cash and cash equivalents amounted to $3.5 billion, current financial assets amounted to $0.9 billion and total capital amounted to $7.3 billion. The current cash situation and the anticipated cash generation and usage are the most important parameters in assessing the capital structure. The Company’s objective is to maintain the capital structure at a level to be able to finance its activities for at least twelve months. Cash income from operations is taken into account and, if needed and possible, the Company can enter into financing agreements or issue new shares. Credit risk Credit risk refers to the risk that a counterparty will default on its contractual obligations resulting in financial loss to the Company. The Company has adopted a policy of only dealing with creditworthy counterparties and obtaining sufficient collateral, where appropriate, as a means of mitigating the risk of financial loss from defaults. Concentrations in credit risk are determined based on an analysis of counterparties and their importance on the overall outstanding contractual obligations at year-end. The Company's commercial revenue are concentrated as discussed in “Note 16 — Segment Reporting”, on a limited number of U.S. customers with high quality creditworthiness. The Company sets customer specific credit limits in order to reduce credit risk from commercial payors. The Company applied the IFRS 9 simplified approach to measuring expected credit losses which uses a lifetime expected loss allowance for trade receivables. To measure the expected credit losses, receivables have been grouped based on credit risk characteristics and the days past due. The provision for expected credit losses was not significant given that there have been no significant credit losses over the last three years and the high quality nature of the Company’s customers. Cash and cash equivalents and current financial assets are invested with several highly reputable banks and financial institutions. The main purpose of the Cash Investment Policy is to preserve the available cash and to ensure sufficient short-term liquidity at all times. Therefore, the Company holds its cash and cash equivalents, in addition to current financial assets mainly with banks which are independently rated A- or higher. Amounts of cash held with banks rated lower than A- are limited to insignificant balances. The maximum amount and tenor of term accounts depends on the rating of the counterparty bank. The Company also holds cash equivalents in the form of money market funds with a low historical volatility. These money market funds are highly liquid investments and can be readily convertible into a known amount of cash. The company has adopted a policy whereby money market funds must have a minimum rating of A, and whereby 95% of its money market funds should have a AAA-rating. 146 Table of Contents Liquidity risk The Company manages liquidity risk by maintaining adequate reserves, by continuously monitoring forecast and actual cash flows, and by matching the maturity profile of financial assets and liabilities. The Company’s main sources of cash are the sale of commercial product and exercise of stock options. This cash is invested in savings accounts, term accounts and money market funds. These money market funds represent the majority of the Company’s available sources of liquidity. Since all of these are immediately tradable and convertible in cash they have an important mitigating effect on any short-term liquidity risk. As of December 31, 2025, the Company had lines of credit totaling $29 million with financial institutions mainly relating to leasing guarantees. Interest rate risk The only variable interest-bearing financial instruments are cash and cash equivalents and current financial assets. Changes in interest rates may cause variations in interest income resulting from short-term interest-bearing assets. Lower short-term interests may have a negative impact on the interest income of the Company. For the year ended December 31, 2025, if applicable interest rates would increase/decrease by 50 basis points, this would have a positive/negative impact of $22 million (compared to $8 million for the year ended December 31, 2024 and $8 million for the year ended December 31, 2023 if applicable interest rates would increase/decrease by 25 basis points). Foreign exchange risk The Company undertakes transactions denominated in foreign currencies, causing exposures to exchange rate fluctuations. The Company is mainly exposed to the Euro, Japanese yen, British pound and Swiss franc. To limit this risk, the Company attempts to align incoming and outgoing cash flows in currencies other than USD. The Company further limits its non-USD liquidity holdings when possible. The net exposure to exchange differences of the monetary assets (being from cash and cash equivalents, in addition to current financial assets) of the Company at the end of the reporting period are as follows: As of December 31, (in thousands of $) 2025 2024 2023 EUR 155,757 756,676 923,773 Other currencies 1,258 1,679 8,708 On December 31, 2025, if the EUR would have strengthened/weakened versus the USD by 10 %, this would have had a negative/positive impact of $16 million, compared to $76 million and $92 million on December 31, 2024 and December 31, 2023, respectively. If other currencies would have strengthen or weakened against the USD by 10%, this would have had no significant impact in all reported periods.

A.[RESERVED] B.CAPITALIZATION AND INDEBTEDNESS Not applicable. C.REASONS FOR THE OFFER AND USE OF PROCEEDS Not applicable. D.RISK FACTORS Our business faces significant risks, including those described below. You should carefully consider all of the information set forth in this Annual Report and in our other filings with the SEC, including the following risk factors. Our business, financial condition or results of operations could be materially and adversely affected if any of these risks occur. These are not the only risks argenx faces. Additional risks and uncertainties not presently known to argenx or that it currently considers immaterial or not specific may also impair its business, results of operation and financial condition. This report also contains forward-looking statements that involve risks and uncertainties. Our actual results could differ materially and adversely from those anticipated in these forward-looking statements as a result of certain factors including the risks described below and elsewhere in this Annual Report and as may be described in our subsequent SEC filings. See “Cautionary Statement with Respect to Forward-Looking Statements”. Risk Factors Related to Commercialization of argenx’s Products and Product Candidates, Including for New Indications The commercial success of our products and product candidates, including in new indications or methods of administration, will depend on the degree of market acceptance. Our products and product candidates, including for any new indications or methods of administration, if and when approved and available on the market, may never achieve an adequate level of acceptance by physicians, patients, the medical community, or healthcare payors for us to be profitable or sustain net profitability in the future. This will depend on a number of factors, many of which are beyond our control, including, but not limited to: •consumer perceptions or publicity regarding our business or the efficacy, safety and quality of the products and product candidates in our profile, our clinical trials for new indications, or any similar products distributed by other companies, and the prevalence and severity of any adverse effects discovered before or after marketing approval has been received; •approval may be for indications, dosage and methods of administration or patient populations that are not as broad as intended or desired; •changes in the standard of care for the targeted indications for any product and product candidate; •relative availability, cost, and convenience of alternative approved therapies; •labeling may require significant use or distribution restrictions or safety warnings; 2 Table of Contents •acceptance by physicians, public health bodies, patients and healthcare payors of each product as safe, effective and cost-effective; and •patients continued commitment required to receive periodic in-center infusions. In addition, because we are developing our products and product candidates for the treatment of different indications, negative results in a clinical trial evaluating the efficacy and safety of a product or product candidate for one indication, including by one of our competitors, could negatively impact the perception of the efficacy and safety of such product or product candidate in a different indication, which could have an adverse effect on our reputation, commercialization efforts and financial condition. Moreover, efforts to educate the medical community and third-party payors on the benefits of our products and product candidates may require significant resources and may never be successful. If our product candidates or methods of use of existing products or new indications fail to gain market acceptance, it will have a material adverse impact on our ability to generate revenues. Even if some products achieve market acceptance, they may not be able to retain market acceptance and/or the market may prove not to be large enough to allow us to generate significant revenues. We face significant competition for our drug discovery and development efforts. The market for pharmaceutical products is highly competitive and characterized by rapidly growing understanding of disease biology, quickly changing technologies, strong intellectual property barriers to entry, and a multitude of companies involved in the creation, development, and commercialization of novel therapeutics. Many of these companies are highly sophisticated and often strategically collaborate with each other. Competition in the autoimmune field is intense and involves multiple mAbs, other biologics and small molecules either already marketed or in development by many different companies including, but not limited to, large pharmaceutical companies such as AstraZeneca plc, AbbVie, Inc., Amgen, Inc., Biogen Inc., GlaxoSmithKline plc, F. Hoffman-La Roche AG, Johnson & Johnson Innovation, Inc. and Novartis AG. In addition, these and other pharmaceutical companies have mAbs or other biologics in clinical development for the treatment of autoimmune diseases. Currently, our commercial revenue is generated by VYVGART and VYVGART SC in gMG, CIDP and ITP (Japan only). We face and expect to continue to face intense competition from other biopharmaceutical companies, who have launched or are developing products for the treatment of gMG and/or CIDP and other autoimmune diseases, including products that are in the same class as VYVGART, as well as products that are similar to some of our product candidates. Competition for other potential future indications is also fierce, with significant development by competitors in almost all of the indications we are currently developing or planning to develop for our product or product candidates. For example, we are aware of certain biopharmaceutical companies selling products for the treatment of adult patients with gMG, and several biopharmaceutical companies are developing drugs that may have utility for the treatment of gMG and/or CIDP. Competitive product launches may erode future sales of our products, including our existing products and those currently under development, or result in unanticipated product obsolescence. Such launches continue to occur, and potentially competitive products are in various stages of development. We could also face competition for use of limited international infusion sites, particularly in new markets as competitors launch new products. We cannot predict with accuracy the timing or impact of the introduction of competitive products that treat diseases and conditions like those treated by our products or product candidates. In addition, our competitors and potential competitors compete with us in recruiting and retaining qualified personnel in all areas of our business, establishing clinical trial sites, registering patients for clinical trials, as well as in acquiring technologies complementary to, or necessary for, the development of our products. Competition is also increasing from companies that are utilizing artificial intelligence and other computational approaches for the development of products. These competitors may incorporate artificial intelligence into their businesses more quickly or more successfully than us, which could impair our ability to compete effectively and adversely affect our results of operations. We anticipate that we will continue to face increasing competition in the future as new companies enter our market and scientific developments surrounding the pharmaceutical market continue to accelerate. We cannot predict the extent to which these developments will impact potential future sales of our products or our product candidates. There can be no assurance that our competitors are not currently developing, or will not in the future develop, technologies and products that are equally or more effective, are more economically attractive, and can be administered more easily than any of our current or future technologies or products. Such competing products or technology platforms may gain faster or greater market acceptance than our products or technology platforms. If we, our products and product candidates or our technology platforms do not compete effectively, it is likely to have a material adverse effect on our business, financial condition and results of operation. 3 Table of Contents We will face significant challenges in successfully commercializing our products and additional product candidates after they are launched. The commercialization of VYVGART in new indications or other product candidates if and when approved, or entrance of any of our products or product candidates into new markets will require us to further expand our sales and marketing organization, enter into collaboration arrangements with third parties, outsource certain functions to third parties, or use some combination of each. We have built, and continue to expand, our sales force in certain of the countries where VYVGART is approved and plan to further develop our sales and marketing capabilities to promote our products, and product candidates, including new indications, if and when marketing approval has been obtained in other relevant jurisdictions. Even if we successfully expand our sales and marketing capabilities, either on our own or in collaboration with third parties, we may fail to launch or market our products effectively. Recruiting and training a specialized sales force is expensive and the costs of expanding an independent sales, marketing and/or promotion organization could be greater than we anticipate. We could further encounter difficulties in our sales or marketing, due to regulatory actions, shut-downs, work stoppages or strikes, approval delays, withdrawals, recalls, penalties, supply disruptions, shortages or stock-outs at our facilities or third-party facilities that we rely on, reputational harm, the impact to our facilities due to natural or man-made disasters, product liability, and/or unanticipated costs. In addition, recruiting and training a sales force is time-consuming and could delay any product launch. In the event that any such launch is delayed or does not occur for any reason, we would have prematurely or unnecessarily incurred these commercialization expenses, and our investment would be lost if we cannot retain or reposition our sales and marketing personnel. Our products and product candidates for which we have obtained or intend to seek approval as biological products, including for new indications, may face biosimilar competition. In the U.S., the Biologics Price Competition and Innovation Act (BPCIA) created an abbreviated approval pathway for biological products that are demonstrated to be “biosimilar” to or interchangeable with a U.S. FDA-licensed reference biological product. However, during the 12-year regulatory exclusivity period applicable to reference biological products, another company may still market a competing version of the reference product if the FDA approves a full BLA for the competing product containing the sponsor’s own preclinical data and data from adequate and well- controlled clinical trials of their product. We believe that any of our product candidates approved as a biological product under a BLA in the U.S. should qualify for the Biologics Price Competition and Innovation Act 12-year period of exclusivity, as is the case with VYVGART. The base regulatory exclusivity period for VYVGART is expected to extend until December 2033 in the U.S. whereas regulatory protection in the EU is expected to expire in August 2032. However, in the U.S., there is a risk that this exclusivity could be shortened due to congressional action or otherwise, or that the FDA will not consider our product candidates to be reference products for competing products, potentially creating the opportunity for competition by biosimilar products sooner than anticipated. The same applies to the EU, as there is also a risk that this exclusivity could be shortened due to legislative actions. We are aware that some of our competitors may be actively developing competing or biosimilar products for VYVGART. It is possible our competitors will be successful in developing biosimilar or interchangeable products for our products and product candidates, and the approval of such competing products may lead to substantial competition in the market, a decrease in sales, or force us to make VYVGART available at lower prices due to competitive pressures. Moreover, an interchangeable biosimilar product, once approved, may be substituted under existing state laws for any one of our reference products. In addition, the Further Consolidated Appropriations Act, 2020, which incorporated the framework from the Creating and Restoring Equal Access To Equivalent Samples (CREATES) legislation, allows biosimilar developers to obtain access to reference biological products, which may facilitate the development of biosimilars to our products. The FDA has also recently issued guidance eliminating the need for data from comparative clinical efficiency studies to demonstrate biosimilarity in many circumstances, which may accelerate biosimilar market entry. If competing or biosimilar products are approved, the market position of our products for existing and recently approved indications may be adversely affected. In the EU, biosimilars are evaluated for marketing authorization pursuant to a set of general and product class-specific guidelines. Moreover, the EU’s legislative bodies are currently working toward finalizing a reform of the EU Pharmaceutical Legislation, likely shortening the baseline of market exclusivity periods for medicinal products. In addition, some EU Member States have adopted, or are considering the adoption of, biosimilar uptake measures or may impose automatic price reductions upon market entry of one or more biosimilar competitors. While the degree of competitive effects of biosimilar competition among EU Member States may vary, continuation of policies promoting 4 Table of Contents biosimilar products in the EU and in EU Member States could erode market share or introduce competitive pricing pressures for our products and product candidates. Enacted and future legislation and regulations could impact demand for our products which could impact our business and future results of operations. In the U.S. and the EU and other jurisdictions, there have been a number of legislative and regulatory changes to healthcare systems that could affect our future results of operations. Governmental regulations that mandate price controls or limitations on patient access to our products or establish prices paid by government entities or programs for our products could impact our business, and our future results of operations could be adversely affected by changes in such regulations or policies. In particular, there have been and continue to be a number of initiatives at the U.S. federal and state levels that seek to reduce healthcare costs in general and the cost of pharmaceuticals in particular, including pharmaceutical pricing reforms under the IRA. The IRA authorizes Medicare drug price negotiation, imposes inflation-based rebate obligations and significantly redesigns the Medicare Part D benefit, including establishing manufacturer discount requirements and capping beneficiary out-of-pocket costs. Although the program remains subject to legal challenges, the IRA is being implemented and may materially reduce the prices we are able to charge for our products, increase our rebate and discount obligations, and affect coverage, formulary placement and demand for our products and product candidates. See “Item 4.B. — Business Overview — Intellectual property — Regulation — Coverage, Pricing and Reimbursement ” for additional details. The HHS has and will continue to issue and update guidance and rulemaking as these IRA programs are implemented. We cannot predict how the HHS will interpret the IRA in the future, or whether the U.S. Congress will enact legislation that further amends the law. However, at this time, the Trump administration is continuing to implement the IRA. Manufacturers that fail to comply with the IRA may be subject to significant penalties, including civil monetary penalties and excise taxes. The IRA also extends enhanced subsidies for individuals purchasing health insurance coverage in ACA (as defined below) marketplaces through plan year 2025. To date, none of the legislative attempts to extend the subsidies has been enacted. While the full economic impact of IRA is unknown at this time, the law’s passage is likely to affect the pricing of our products and product candidates. The adoption of restrictive price controls in new jurisdictions, more restrictive controls in existing jurisdictions, the adoption of these lower prices by commercial payors, or the failure to obtain or maintain timely or adequate pricing could also adversely impact revenue. We expect pricing pressures will continue globally. Further, at the U.S. state level, legislatures are increasingly enacting laws and implementing regulations designed to control pharmaceutical and biological product pricing, including price or reimbursement constraints, discount requirements, price transparency reporting, and programs designed to encourage importation from other countries and bulk purchasing. States are also enacting laws modeled on federal policies, such as the IRA and the 340B drug discount program. We expect that additional state and federal healthcare reform measures will be adopted in the future, any of which could limit the amounts that federal and state governments will pay for healthcare products and services, including pharmaceuticals, which could result in reduced demand for our products and product candidates or additional pricing pressures. The EU, on the other hand, is in the final stages of adopting new EU Pharmaceutical Legislation in 2026, reforming its legislative framework for medicinal products (see “Item 3.D — Risk Factors — Agreement on new EU Pharmaceutical Legislation”). Depending on the final text, which has yet to be published and is still subject to formal approval, the impact could be positive with respect to certain regulatory processes. Other aspects may, however, have a negative impact on innovative pharma and biotech companies such as argenx. In particular, this may be the case for the envisaged shorter baseline market exclusivity periods. In any case, these legislative changes will only enter into effect after a (not yet specified) transitional period, which will most likely conclude in 2028 the earliest. We are subject to government pricing laws, regulation and enforcement, which affect the prices we may charge the government for our products and the reimbursement our customers may obtain from the government. Changes in such laws, regulation, and enforcement may place downward pressure on the prices we can charge in the marketplace, and our failure to comply with these laws could harm our results, operations and/or financial conditions. In the U.S., we are required to participate in various government programs for our products to be reimbursed or purchased by the federal government. We participate in programs such as the Medicaid Drug Rebate Program, the 340B drug discount program, Medicare Part B, Medicare Part D and the U.S. Department of Veterans Affairs Federal Supply Schedule pricing program. The requirements vary by program, but we are, among other things, required to enter into 5 Table of Contents agreements with and calculate and report prices and other information to certain government agencies, charge no more than statutorily mandated ceiling prices and calculate and pay rebates and refunds for certain products. The calculations are complex and are often subject to interpretation by us, governmental agencies and the courts. If we determine that the prices we reported were in error, we may be required to restate those prices and pay additional rebates or refunds to the extent we understated the rebate or overcharged the government due to the error. Additionally, there are penalties associated with submission of incorrect pricing or other data by the specified deadline, as well as potential allegations under the False Claims Act and other laws and regulations. Statutory or regulatory changes, including changes in CMS guidance, could affect the average sales price calculations and the resulting Medicare payment rate for VYVGART and our potential future products. Any such measures may increase our financial obligations to government payors, reduce net realized prices, and adversely affect the demand, coverage and overall sales of our products. In addition, maintaining compliance with these government price reporting and discounting obligations is time-consuming and costly, and a failure to comply can result in substantial fines, penalties, all of which could adversely impact our financial results. See “Item 4.B. — Business Overview — Intellectual property — Regulation — Coverage, Pricing and Reimbursement” for additional details on the regulatory framework regarding the coverage, pricing and reimbursement of our products and product candidates. In addition, the current U.S. Presidential administration has taken several steps to try to align U.S. drug prices with drug prices in other countries through an approach known as MFN pricing, On November 6, 2025, CMS announced the GENEROUS Model under its CMMI authority. The GENEROUS Model is a voluntary model that tests the impact of CMS-facilitated supplemental rebate agreements that align the Medicaid net price with a defined MFN price. In December 2025, CMS issued proposed rules for the GLOBE Model and the GUARD Model under its CMMI authority. The GLOBE and GUARD Models are mandatory models that, if finalized, would require manufacturers of certain drugs to pay additional rebates based on the difference between the Medicare price and the price in market basket countries. CMS proposes that the new rebate would apply to utilization by approximately 25% of Medicare Part B fee-for-service beneficiaries and 25% of Medicare Part D enrollees. In Congress, there also are pending legislative proposals that, if enacted, would require MFN pricing in certain healthcare programs. It is also currently uncertain how these U.S. policy efforts to align US pharmaceutical pricing more closely to international benchmarks from countries with competing healthcare cost containment measures will affect our business. Any expansion, finalization or implementation of these or similar MFN-based pricing initiatives could subject our products to additional rebate obligations, negatively impact our pricing strategies, product demand, or competitive positioning across global markets, and may result in reduced revenue in critical markets. We may not obtain or maintain adequate pricing and coverage or reimbursement status for our products and product candidates. Sales of VYVGART and our product candidates, if approved, will depend, in part, on the extent to which third-party payors, including government health programs in the U.S. (such as Medicare Parts B and D and Medicaid) and other countries, commercial health insurers, and managed care organizations, provide coverage and establish adequate reimbursement levels for such products and product candidates. Patients generally rely on third-party payors to reimburse all or part of the associated healthcare costs, and are unlikely to use our products unless coverage is provided and reimbursement is adequate to cover a significant portion of the cost of our products. In the U.S., no uniform policy of coverage and reimbursement for products exists among commercial third-party payors. Commercial third-party payors decide which products they will pay for and establish reimbursement levels, often relying upon Medicare coverage policy and payment limitations. However, decisions regarding the extent of coverage, formulary tier placement, utilization management requirements (including step therapy), and the amount of reimbursement to be provided for any product candidate that we develop through approval will be made on a plan-by- plan basis. Even under U.S. government healthcare programs such as Medicare and Medicaid, coverage and reimbursement policies can vary significantly. Medicare Part D is administered by commercial insurance companies under contract with the CMS, and their coverage and reimbursement policies may vary, subject to certain statutory and regulatory requirements. Additionally, Medicaid programs vary from state to state in their coverage policies and reimbursement rates, subject to certain federal requirements. Further, from time to time, typically on an annual basis, payment rates are updated and revised by third-party payors. Such updates could impact the demand for our products, to the extent that patients who are prescribed our products, if approved, are not separately reimbursed for the cost of the product. The process for determining whether a third-party payor will provide coverage for a product may be separate from the process for setting the price of a product or for establishing the reimbursement rate that such a payor will pay for the product. Even if we do obtain adequate levels of reimbursement, third-party payors, such as government or private healthcare insurers, carefully review and increasingly question the coverage of, and challenge the prices charged for, 6 Table of Contents products. Increasingly, third-party payors are requiring that biopharmaceutical companies provide them with predetermined discounts from list prices and are challenging the prices charged for products. We may also be required to conduct expensive pharmacoeconomic studies to justify the coverage and the amount of reimbursement for particular medications. We cannot be sure that coverage and reimbursement will be available for any product that we commercialize and, if reimbursement is available, what the level of reimbursement will be. Moreover, coverage policies and third-party payor reimbursement rates may change at any time. Therefore, even if favorable coverage and reimbursement status is attained for one or more products for which we receive marketing approval in one or more indications, less favorable coverage policies and reimbursement rates may be implemented in the future. For instance, even though favorable coverage and reimbursement status has been attained for VYVGART for the treatment of gMG and CIDP in the U.S., access to VYVGART for any other indication may be reduced or restricted by limited payor coverage due to treatment criteria, which may prevent us from realizing its full commercial potential. In addition, the coverage and reimbursement levels for our products for the treatment in one indication may have an adverse impact on the coverage and reimbursement levels of such products or product candidates in other indications for which marketing approval has previously been or may subsequently be obtained. Inadequate coverage or reimbursement may diminish or prevent altogether any significant demand for our products and/or may prevent us entirely from entering certain markets or indications, which would prevent us from generating significant revenues or sustaining net profitability in the future, which would adversely affect our business, financials and results of operations. In many foreign countries, pricing, coverage, and level of reimbursement of prescription drugs are subject to governmental and/or third-party payor control, and we and our collaborators may be unable to obtain coverage, pricing, and/or reimbursement on terms that are favorable to us or necessary for us or our collaborators to successfully commercialize our marketed products in those countries. In some foreign countries, the proposed pricing for a drug must be approved before it may be lawfully marketed. The requirements governing drug pricing and reimbursement vary widely from country to country, and may take into account the clinical effectiveness, cost, and service impact of existing, new, and emerging drugs and treatments. For example, in the EU, pricing and reimbursement of medicinal products, is almost exclusively a matter for national, rather than EU, provisions and regulations. EU Member States may restrict the range of medicinal products for which their national health insurance systems provide reimbursement and may control the prices of medicinal products for human use. An EU Member State may approve a specific price for the medicinal product or it may instead adopt a system of direct or indirect controls on the profitability of the company placing the medicinal product on the market. Our results of operations may suffer if we or our collaborators are unable to market our products in foreign countries or if coverage and reimbursement for our marketed products in foreign countries is limited or delayed. Downward price pressures in the EU and other countries may, in turn, contribute to downward price pressure in the U.S. because of MFN initiatives. If we fail to obtain orphan drug designation or we do not have valid and enforceable patents covering our products and their uses and product candidates and fail to obtain and/or maintain orphan drug exclusivity for our products or product candidates, our competitors may be able to sell products to treat the same conditions and our revenue may be reduced. We have and may from time to time seek orphan drug designation in the U.S., Japan and, the EU for certain indications addressed by our products and product candidates. With regard to these designations or future designations we may obtain, we may not be the first to obtain marketing approval of these drugs for such indication due to the uncertainties associated with developing therapeutic products, and we may not obtain orphan exclusivity upon approval. In the U.S., orphan drug exclusivity applies only to the specific uses or indications for which a drug is approved within the designated rare disease or condition, and therefore may be narrower than the scope of the original orphan designation. In addition, exclusive marketing rights in the U.S. may be limited if we seek approval for an indication broader than the orphan-designated indication, or may be lost if the FDA later determines that the request for designation was materially defective or if we are unable to assure sufficient quantities of the product to meet the needs of patients with the rare disease or condition. Further, even if we obtain orphan drug exclusivity for a product, that exclusivity may not effectively protect the product from competition because different drugs with different active moieties or different principal molecular structural features can be approved for the same condition. Even after an orphan drug is approved, the MHRA, the EMA, respectively the European Commission, the FDA, the MHLW (collectively, the Relevant Regulatory Authorities) or other comparable regulatory authorities can subsequently approve the same drug with the same principal molecular structural features for the same condition if the regulator concludes that the later drug is safer, more effective, or makes a major contribution to patient care. 7 Table of Contents Risk Factors Related to the Development and Clinical Testing of argenx’s Products and Product Candidates Failure to successfully identify, select and develop our products in other indications, or additional products or product candidates could impair our ability to grow. Our long-term growth strategy entails developing and marketing additional products and product candidates, including efgartigimod for new indications, empasiprubart and adimanebart. This requires substantial resources, whether or not any product candidates or new indications are ultimately identified. The success of this strategy depends partly upon our ability to identify, select, develop, and ultimately, commercialize promising product candidates. We are heavily dependent on precise, accurate and reliable scientific data to identify, select and develop promising product candidates and products. Our business decisions may therefore be adversely influenced by inaccurate, improper or fraudulent scientific data, including data sourced from third parties. Even with accurate scientific data, our technology platforms may fail to discover and to generate additional products and products candidates, that are suitable for further development. Even if we identify additional product candidates, they may not be suitable for clinical development as a result of harmful side effects, limited efficacy or other characteristics that indicate that it is unlikely to be a product that will receive approval by the Relevant Regulatory Authorities, and other comparable regulatory authorities or achieve market acceptance. If we do not successfully identify, develop and commercialize product candidates and VYVGART in new indications based upon our technological approach, we may not be able to obtain product or collaboration revenues in future periods. Obtaining regulatory approval for our products and product candidates is inherently uncertain. To obtain the requisite regulatory approvals to market and sell any of our products and product candidates, we or our collaborators for such candidates must successfully demonstrate that our products are safe and effective in humans. Clinical trials are expensive and can take many years to complete, and their outcome is inherently uncertain. Further, success in early clinical trials or in one indication does not guarantee success in later clinical trials or in other indications. Failure to successfully develop or obtain marketing approval for our products and product candidates could negatively impact our business. The time required to obtain approval by the Relevant Regulatory Authorities and other comparable regulatory authorities is unpredictable but typically takes many years, if obtained at all, following the commencement of clinical trials and depends upon numerous factors, including the substantial discretion or interpretation of the regulatory authorities. This lengthy approval process as well as the unpredictability of future clinical trial results may result in our failing to obtain regulatory approval to market any of our product candidates, including for new indications. We have experienced delays in our prior clinical trials, and we may experience delays in our ongoing or planned clinical trials, for a large variety of reasons outside our control in complying with regulatory approvals which can adversely affect the timing of clinical trials, including as described in “Item 3.D. — Risk Factors — Risk Factors Related to Other Government Regulations — All aspects of our business ranging from preclinical, clinical trials, marketing and commercialization are highly regulated and any delay by relevant regulatory authorities could jeopardize our development and approval process or result in other suspensions, refusals or withdrawal of approvals.” Over the last several years, the U.S. government has shut down several times and average review times at the FDA have fluctuated in recent years as a result. If a prolonged government shutdown occurs it could significantly impact the ability of the FDA to timely review and process our regulatory submissions. Inadequate funding for the FDA and other government agencies, or other disruptions to these agencies’ operations, could also prevent new products and services from being developed or commercialized in a timely manner or otherwise prevent those agencies from performing normal functions on which the operation of our business may rely, which could negatively impact our business. In addition, ongoing efforts by the current U.S. Presidential administration to limit the size of the FDA and other agencies of HHS, including through reductions in staff, may further increase the unpredictability in approval timelines for our products and product candidates. In 2025, HHS announced and implemented a restructuring that included significant reductions in the FDA’s workforce pursuant to an executive order directing federal workforce optimization. These staffing reductions together with resignations, resulting in leadership turnover and loss of institutional knowledge, may disrupt agency operations and adversely affect the timing, consistency or outcome of regulatory review. Ongoing initiatives by the current U.S. Presidential administration to deregulate and to review the scientific basis for, and otherwise attempt to influence, FDA decisions and policies create regulatory uncertainty for pharmaceutical companies. 8 Table of Contents Additionally, uncertainty remains as to how the FDA’s agency-wide implementation of ELSA, a generative artificial intelligence tool, including for review of drug product applications, as well as its deployment of agentic artificial intelligence capabilities, will impact the outcomes and timeliness of FDA reviews and other activities. In addition, the future of the currently applicable Prescription Drug User Fee Act construct to ensure timely FDA review of applications may be impacted due to expressed concerns about the effect on industry-FDA relations, and staffing shortages. If we are unable to obtain regulatory approval of our products and product candidates on a timely basis or at all, our business, financial operations and/or financial condition may be impacted. Certain of our clinical trials have not succeeded, and may in the future also not succeed, and even if they succeed, we may not obtain regulatory approval for our products or product candidates or regulatory approval may be delayed. Certain of our clinical trials have not succeeded, and may in the future also not succeed. We could experience operational challenges as we undertake an increasing number of clinical trials, including those conducted in countries outside the EU, UK and the U.S. that may subject us to further delays and expenses as a result of increased shipment costs, additional regulatory requirements and the engagement of non-EU, non-UK and non-U.S. contract research organizations (CROs). Such trials may also expose us to risks associated with clinical investigators and institutions who apply different standards of diagnosis, screening and medical care or are otherwise unfamiliar with standards and requirements imposed by the Relevant Regulatory Authorities. If we experience delays in the completion of, or termination of, any clinical trial of our products or product candidates, may increase our costs, slow down our product candidate development and approval process and jeopardize our ability to commence product sales and generate revenues. Many of the factors that cause, or lead to, a delay in the commencement or completion of clinical trials may also ultimately lead to the denial of regulatory approval of our product candidates or result in the development of our product candidates being stopped early. Significant clinical trial delays could also allow our competitors to bring products to market before we do or shorten any periods during which we have the exclusive right to commercialize our products and product candidates. Even if clinical trials are initiated, our development efforts may not be successful. Even if we obtain positive results from preclinical trials or initial clinical trials, we may not achieve the same success in future clinical trials, which may negatively impact the price of our ordinary shares or ADSs. Regulatory approval of our products or product candidates may be delayed or refused for many reasons, including for reasons outside our control. Some of the reasons for regulatory delay or refusal include: •the Relevant Regulatory Authorities or other comparable regulatory authorities may disagree with the design or implementation of our clinical trials; •we may be unable to demonstrate, to the satisfaction of the Relevant Regulatory Authorities or other comparable regulatory authorities, that our product candidates are safe, pure, potent and effective for any of their proposed indications; •the results of clinical trials may not meet the level of statistical significance required by the Relevant Regulatory Authorities or other comparable regulatory authorities for approval; •the chemistry, manufacturing and controls information submitted in an application is insufficient; and •the facilities of third-party manufacturers with which we contract for the manufacture of our product candidates are not adequate to support approval of our product candidates. Any of these occurrences may harm our business, results of operations and financial condition significantly. If we decide to pursue accelerated approval for any of our product candidates, it may not lead to faster development or regulatory review or approval and we may still need to conduct additional clinical trials, which could increase the expense of obtaining, if at all, necessary marketing approvals. The accelerated approval pathway has come under scrutiny by various stakeholders, and the Food and Drug Omnibus Reform Act of 2022 (FDORA) revised the requirements for this pathway. Although this legislation did not change the standard for accelerated approval, it authorized the FDA to require a post-approval clinical trial to be underway prior to approval or within a specified time period following approval, and must specify conditions of any required post-approval clinical trial. FDORA also requires sponsors to submit progress reports for required post-approval studies. Failure to 9 Table of Contents conduct due diligence for required post-approval studies is deemed a prohibited act under the FDCA. FDORA also details procedures the FDA must follow to withdraw an accelerated approval on an expedited basis, including where the required post-approval studies are not conducted with due diligence or fail to verify clinical benefit, other evidence demonstrates that the product is not shown to be safe or effective under the conditions of use, or the sponsor disseminates false or misleading promotional materials with respect to the product. FDA has been exercising these authorities and has issued guidance documents regarding the accelerated approval pathway. If we decide to pursue accelerated approval for any of our product candidates, the failure to obtain accelerated approval (or the withdrawal of any accelerated approval) could result in a longer time period to commercialization of such product candidate, if any, and could increase the cost of development of such product candidate and harm our competitive position in the marketplace. For example, if standard of care were to evolve or if any of our competitors were to receive approval for a drug or biological product for a disease or condition for which we are seeking accelerated approval before we receive accelerated approval, we may not be able to demonstrate that our product candidate provides a meaningful advantage over other available therapies and accelerated approval may not occur. Our products and product candidates may have adverse, undesirable or unacceptable side effects, and we or others may identify undesirable or unacceptable side effects caused by any of our products or product candidates before and after they have received marketing approval. Undesirable side effects that may be caused by our product candidates, or by the combination of our product candidates with other medical products, could cause us or regulatory authorities to interrupt, delay or halt clinical trials and could result in more restrictive labeling or the delay or denial of regulatory approval by the Relevant Regulatory Authorities or other comparable regulatory authorities. We have observed adverse events and treatment emergent adverse events in our clinical trials, and we may see additional adverse events and treatment emergent adverse events in our ongoing and future clinical trials. Such side effects may be more serious than those observed to date, and as a result, our ongoing and future clinical trials may be negatively impacted. Moreover, as we seek to develop product candidates, including products in new indications, patients may experience new or more serious effects. Drug-related side effects caused by any of our products or product candidates that we or others identify could, among other things, affect patient recruitment, the ability of enrolled patients to complete the clinical trial, result in potential product liability claims, damage sales of our existing products, result in significant reputational damage for us and our product development, and other issues including the delay of other programs. Any undesirable drug-related side effects can also cause the Relevant Regulatory Authorities or other comparable regulatory authorities to withdraw approvals or revoke licenses of such products and require us to take such products off the market, require the addition of labeling statements, specific warnings, or a contraindication or other modification of the product labeling, request the issuance of safety alerts, require a REMS to ensure that the benefits of the product outweigh its risks, and/or require us to change the way the product is administered, conduct additional clinical trials or change the labeling of the product. If our target patient population is smaller than expected, we are unable to successfully enroll and retain patients in our clinical trials, or experience significant delays in doing so, we may not realize the full commercial potential of any products or product candidates. Currently, we mainly develop products or product candidates for the treatment of rare diseases for which the target patient population can be small. If the actual number of patients with these disorders is smaller than we expected, we may encounter difficulties in enrolling sufficient patients in our clinical trials, thereby delaying or preventing development and approval of our products or product candidates. Physicians, who are an important source of patients for clinical trials, may also be less familiar with these rare diseases and may therefore fail to identify these conditions in their patients and therefore may not refer them to our clinical trials. Patient enrollment, a significant factor in the timing of clinical trials, depends on many factors, including the size and nature of the patient population, eligibility criteria for the clinical trial, the proximity of patients to clinical sites, competition for patient recruitment from competing clinical trials, the design of the clinical trial, the availability of alternate approved therapies for the indication the clinical trial is investigating, and clinicians’ and patients’ perceptions as to the potential advantages of the drug being studied in relation to other available therapies. We compete with other companies to enroll target patient populations, as set forth in “Item 3.D. Risk Factors — Risk Factors Related to Commercialization of argenx’s Products and Product Candidates, Including for New Indications—We face significant competition for our drug discovery and development efforts.” Even if product candidates obtain significant market share for their approved indications, because certain potential target populations are small, we may never recoup our investment in such product candidate without obtaining regulatory approval for additional indications for such product candidates. Even once enrolled, we may be unable to retain a sufficient number of patients to complete any of our clinical trials. In addition, any negative results we may report in clinical trials of our drug candidates may make it difficult or impossible to recruit and retain patients in other clinical trials of that same drug candidate. Delays in the completion of any clinical 10 Table of Contents trial of our product candidates will increase our costs, slow down our product candidate development and approval process and delay or potentially jeopardize our ability to commence product sales and generate revenue. In addition, some of the factors that cause, or lead to, a delay in the commencement or completion of clinical trials may also ultimately lead to the denial of regulatory approval of our product candidates. Risk Factors Related to argenx’s Dependence on Third Parties We rely, and expect to continue to rely, on third parties to conduct some of our research activities, manufacturing and clinical trials and for parts of the development and commercialization of our existing and future research programs, products and product candidates. If our relationships with such third parties are not successful, our business may be adversely affected. We have relied upon and plan to continue to rely upon third parties, including independent clinical investigators, CROs, CMOs and other third-party service providers with the applicable protocol, legal and regulatory requirements and scientific standards, and our reliance on these third parties does not relieve us of our regulatory responsibilities. To the extent our collaborators or the CROs or investigators fail to enroll participants for our clinical trials, fail to conduct the clinical trial to GCP standards or in full compliance with legal and regulatory requirements or are delayed for a significant time in the execution of clinical trials, including achieving full enrollment, we may be affected by increased costs, program delays or both, which may harm our business. In addition, we are, and expect to continue to be, dependent on partnerships with partners and licensees relating to the development and commercialization of our existing and future research programs, products and product candidates. We currently have collaborative research relationships with various pharmaceutical companies such as AbbVie, Zai Lab and with various academic and research institutions worldwide for the development of product candidates resulting from such collaborations. We also have distribution agreements in place with several distribution partners for VYVGART. We have and will continue to have discussions on potential partnering opportunities with various pharmaceutical companies. If we fail to enter into or maintain collaborations on reasonable terms or at all, our ability to develop our existing or future research programs and product candidates and to commercialize our existing or future products could be delayed, the commercial potential of our products could change and our costs of development and commercialization could increase. While we have agreements governing our relationships with these third parties, we have limited influence over their actual performance and control only certain aspects of their activities. If independent investigators, third-party service providers or CROs fail to devote sufficient resources to the development of our product candidates, or if their performance is substandard, it may delay or compromise the prospects for approval and commercialization of any product candidates that we develop. In addition, our collaborators, CROs, CMOs, distributors, and other third-party service providers are subject to extensive healthcare, regulatory, data privacy, manufacturing, anti-corruption and other laws and regulations. Although we seek to structure our relationships in compliance with applicable laws and regulations and monitor the activities of these third parties, we do not control their day-to-day operations and cannot guarantee that they will comply with all applicable legal and regulatory requirements. Any failure by our third-party partners to comply with such requirements could result in regulatory enforcement actions, monetary penalties, exclusion from government healthcare programs, reputational harm, delays in development or commercialization, or other adverse consequences. In particular, regulatory authorities enforce GCP requirements through periodic inspections of clinical trial sponsors, principal investigators and clinical trial sites. If we, our investigators or any of our CROs fail to comply with applicable GCPs, the clinical data generated in our clinical trials may be deemed unreliable and the Relevant Regulatory Authorities or comparable regulatory authorities may require us to perform additional clinical trials before approving our marketing applications. In addition, our collaborative partners may not adhere to, or may terminate collaboration agreements with, all associated consequences or disagree on the interpretation of contractual terms. We may not be able to control our collaborative partners’ compliance with all applicable requirements for the commercialization of our products, which could adversely affect such commercialization and the profitability of such products. Failures by our collaborative partners to meet their contractual, regulatory, or other obligations to us, or any disruption in the relationships between us and our collaborative partners, could have a material adverse effect on our product pipeline and business. We face significant competition in establishing successful relationships with third-party service providers and appropriate collaborative partners. These third-party service providers may have contractual relationships with other entities, some of which may be our competitors, which may draw their time and resources away from our programs. In addition, some of our third-party service providers or CROs have the ability to terminate their respective agreements with us, and if such agreements terminate, we may not be able to enter into arrangements with alternative CROs or investigators or to do so on commercially reasonable terms. In addition, we may not be able to find appropriate collaboration partners. Disruptions caused by our reliance on third parties for our raw materials and manufacturing process may delay or disrupt our business, product development and commercialization efforts. 11 Table of Contents We do not have the ability to internally source the raw materials necessary to produce our products or product candidates, and do not currently have, nor do we plan to acquire, the infrastructure or capability internally to manufacture our products or product candidates and depend on a worldwide supply chain and third parties for both. Disruptions caused by our reliance on such third-party suppliers, service providers and manufacturers may delay or disrupt our business, product development and commercialization efforts. Reliance on Third-Party Suppliers and Service Providers For some of our raw materials, we rely on a single source of supply and there are limited supplies of the raw materials. If prices increased, or we were to experience an unexpected loss of supply of or if any supplier was unable to meet our demand for any of our products and product candidates, including increased demand if VYVGART is approved for additional indications, we could experience delays in our research or planned clinical trials or risk shortages in commercial supply which could materially impact our revenue potential. These issues could be exacerbated by pressure on the supply chain, for example due to power shortages, natural disasters, extreme weather conditions, public health crises, changed laws or regulations, military conflicts, executive orders, or geopolitical events, including trade disputes, embargoes or economic or financial sanctions enacted as a result of international conflict. The cost of our raw materials may also increase based on actual or threatened trade restrictions or increased tariffs on foreign exports. As we continue to grow our business we may need to establish additional sources of supply for our products. The lead time needed to establish a relationship with a new supplier can be lengthy and require us to devote substantial time and resources, which could result in additional costs, or delays and adversely affect our business. Additionally, certain of the raw materials required in the manufacture and the formulation of our products and product candidates may be derived from biological sources, including mammalian tissues, bovine serum and human serum albumin. There are certain European regulatory restrictions on using these biological source materials including rigorous testing requirements, which could limit or delay production. Regulatory authorities may require additional studies if we adopt a new supplier. If there are changes in the regulation requirements that our suppliers are unable to meet, our clinical development or commercial activities may be delayed or interrupted. We may not be able to engage a back-up or alternative supplier or service provider in a timely manner or at all if any of these third parties were to cease or interrupt production or otherwise fail to supply these materials, products, or services to us for any reasons, including due to regulatory requirements or actions (including recalls), adverse financial developments at or affecting the supplier, failure by the supplier to comply with cGMPs, contamination, business interruptions, or labor shortages or disputes. Interruptions in the supply of these materials, products or services may also result from international conflict, trade disputes, embargoes or economic or financial sanctions imposed, administered or enforced by the UN Security Council, the U.S., the UK, the EU, or the respective governmental institutions of any of the foregoing including, without limitation, the Office of Foreign Assets Control of the US Department of the Treasury, the US Department of Commerce, the US Department of State and any other agency of the US government. Reliance on Third-Party Manufacturing We rely on and expect to continue to rely on CMOs. We also rely on certain third parties to perform filling, finishing, distribution, laboratory testing and other services related to the manufacture and supply of our products and product candidates. We do not control the manufacturing process at our CMOs and are completely dependent on them for the production of our products and product candidates in accordance with relevant regulations (such as cGMPs), although we are responsible for ensuring that our products comply with regulatory requirements. If our CMOs cannot successfully manufacture material that conforms to our specifications and the strict regulatory requirements of the Relevant Regulatory Authorities or other comparable regulatory authorities, our business could be adversely affected, including an inability to initiate or continue clinical trials of product candidates under development, delay in submitting regulatory applications, or receiving regulatory approvals for product candidates, including new indications, subjecting third-party manufacturing facilities to additional inspections by regulatory authorities, requirements to cease distribution or to recall batches of our products or product candidates and an inability to meet commercial demands for our marketed products. Most notably, we contract with Lonza for their manufacturing sites in Slough, UK, Portsmouth, U.S., Singapore and Visp, Switzerland as well as with Fujifilm, based in Denmark, for activities relating to the development of cell banks, development of our manufacturing processes and the manufacturing of drug substance. We use additional contract manufacturers to fill, test, label, package, store and distribute our (investigational) drug products. Our products and product candidates are biologics and require multiple processing steps that are more difficult than those required for most small molecule chemical pharmaceuticals. While we work with our CMOs and partners on optimization, strengthening and upscaling our manufacturing, problems with these manufacturing processes, such as capacity issues, or even minor deviations from the normal process or from the materials used in the manufacturing process, which may not be detectable by us in a timely manner, could lead to manufacturing failures or product defects, resulting in lot failures, product recalls, product liability claims and insufficient inventory. 12 Table of Contents We face risks inherent in relying on limited CMOs, as any failure in their ability to successfully manufacture our products or product candidates as described above or any disruption, such as supply shortages or disruptions of raw materials, fires, pandemics, natural hazards or acts of vandalism at the CMO could significantly interrupt our manufacturing capability. Alternative production plans in place or disaster-recovery facilities available to us may not be sufficient. In case of a disruption, we may have to establish additional alternative manufacturing sources. This would require substantial investment on our part, which we may not be able to obtain on commercially acceptable terms or at all. Additionally, we may experience significant manufacturing delays as we build or locate replacement facilities and seek and obtain necessary regulatory approvals. If this occurs, we will be unable to satisfy manufacturing needs on a timely basis, if at all. Also, operating any new facilities may be more expensive than operating at our current facilities. Further, business interruption insurance may not adequately compensate us for any losses that may occur, and we would have to bear the additional cost of any disruption. For these reasons, a significant disruptive event of the manufacturing facility could have drastic consequences, including placing our financial stability at risk. Accuracy and timing of our financial reporting is partially dependent on information received from third-party partners, which we do not control. We have collaborated, and plan to continue to collaborate, with third parties, including distributor and licensing partners, on certain product candidates. As part of some of these collaborations, our collaboration partners are responsible for providing us with financial information regarding specific projects, including funds spent, liabilities incurred and expected future costs, on which we rely for our own financial reporting. If our collaboration partners fail to provide us with the necessary financial information within the agreed upon timeframes, or if such financial information proves inaccurate, it would adversely impact the timing and accuracy of our own financial reporting. Any inaccuracy in our financial reporting could cause investors to lose confidence in our financial reporting, reputational damage or affect our ability to obtain, and the terms of, any future financing, which may harm our business. Risk Factors Related to Other Government Regulations We are subject to healthcare laws, regulation and enforcement. The failure to comply with these laws could harm our results, operations and/or financial condition. Our current and future operations are and may become directly, or indirectly through our customers and third-party payors, subject to various U.S. federal and state, EU and EU Member State, Japanese, Chinese, UK, Canadian and Israeli healthcare laws, and healthcare laws of other jurisdictions in which we conduct our business. This includes, but is not limited to, the U.S. FDCA, the U.S. False Claims Act and EU Directive 2001/83/EC. In particular, our sales, marketing and business arrangements are subject to healthcare fraud and abuse, anti-kickback and similar laws designed to prevent fraud, misconduct, improper inducements and other abusive practices. For example, EU Directive 2001/83/EC restricts the provision of gifts, pecuniary advantages or other benefits to persons qualified to prescribe or supply medicinal products, subject to limited exceptions. Compliance with these complex and evolving requirements requires significant resources and may constrain our commercial activities. Any action against us for violation of these laws, even if we successfully defend against it, could cause us to incur significant legal expenses and divert our management’s attention from the operation of our business. The shifting compliance environment and the need to maintain robust and expandable systems to comply with multiple jurisdictions with different compliance or reporting requirements increases the possibility that we or our collaborative partners may run afoul of one or more of these requirements. We continue to expand, enhance and refine our internal ethics and compliance function and program to ensure compliance with the different healthcare laws and regulations. As we continue to grow our headcount to support our business, we face increased compliance risk as we need to train and supervise additional personnel to comply with relevant healthcare laws and regulations. This involves substantial costs and, notwithstanding our investment, there can be no assurance that our policies and procedures will be followed at all times or will effectively detect and/or prevent all compliance violations by our employees, consultants, subcontractors, agents and partners. It is possible that governmental authorities will conclude that our business practices do not comply with current or future statutes, regulations or case law involving applicable fraud and abuse or other healthcare laws and regulations. If our operations are found to be in violation of any of these laws or any other governmental regulations applicable to us, we may be subject to significant civil, criminal and administrative investigations, penalties, damages, fines, disgorgement, imprisonment, exclusion of drugs from government funded healthcare programs, such as Medicare and Medicaid in the U.S., additional reporting requirements and oversight, reputational harm and the curtailment or restructuring of our operations. Managing such investigations and defending against or appealing any such actions or penalties can be costly and time-consuming and may require significant financial and personnel resources. Therefore, even if we are successful in managing any such governmental investigations and/or defending against or appealing any such actions or penalties that may be brought against or imposed upon us, our business may be impaired. Efforts to ensure that our business 13 Table of Contents arrangements with third parties comply with applicable healthcare laws and regulations also involve substantial costs, and because we do not fully control the operations or compliance practices of these third parties, we cannot assure you that they will comply with all applicable healthcare laws and regulatory requirements. The scope, interpretation and enforcement of healthcare laws remain uncertain and subject to change, particularly in the current environment of healthcare reform. Federal and state authorities in the U.S. have increased scrutiny of interactions between healthcare companies and healthcare providers, as well as promotional practices, including direct-to-consumer prescription drug advertising and manufacturer-sponsored platforms that facilitate patient access to products. The FDA has also heightened its review of the data supporting advertising and promotional claims. Compliance with these evolving requirements, and responding to investigations or enforcement actions, may require significant time and resources and could divert management attention, result in penalties or otherwise adversely affect our business. All aspects of our business, including preclinical research, clinical trials, marketing and commercialization, are highly regulated, and any delay by relevant regulatory authorities could jeopardize our development and approval process and/or result in suspensions of marketing authorizations, refusals to approve our products, or withdrawal of existing approvals. Before we can commence clinical trials for a product candidate, we must complete extensive preclinical testing to support our IND or planned IND applications in the U.S. or Japan, or our clinical trial applications (CTAs) in the EU, or comparable applications in other jurisdictions. We cannot be sure that we will be able to submit INDs or CTAs or comparable applications for our development programs on the timelines we expect, if at all. We also cannot guarantee that submission of INDs or CTAs or comparable applications will result in the Relevant Regulatory Authorities or other regulatory authorities allowing clinical trials to begin. Clinical trials must be conducted in accordance with applicable laws and regulations, Relevant Regulatory Authorities' and other comparable regulatory authorities’ legal requirements and regulations and are subject to oversight by Relevant Regulatory Authorities and other comparable regulatory authorities as well as IRBs and ethics committees. In particular, clinical trials must be conducted in compliance with GCPs and clinical supplies of our products and product candidates must be produced under cGMPs and other regulations. We could encounter delays if a clinical trial is suspended or terminated, by us, by the IRB or ethics committee, by the data review committee or data safety monitoring board for such clinical trial, or by the Relevant Regulatory Authorities or other comparable regulatory authorities. Such authorities may impose a suspension or termination due to a number of factors, including failure to conduct the clinical trial in accordance with regulatory requirements or our clinical protocols, inspection of the clinical trial operations or clinical trial site by the Relevant Regulatory Authorities or other comparable regulatory authorities resulting in the imposition of a clinical hold, unforeseen safety issues or adverse side effects, including those relating to the class to which our products and product candidates belong, failure to demonstrate a benefit from using the product or product candidate, changes in governmental regulations or administrative actions, or lack of adequate funding to continue the clinical trial. If we experience delays in the completion of, or termination of, any clinical trial of our products or product candidates, the costs of our clinical programs may increase, the commercial prospects of our products and product candidates may be harmed, and our ability to generate product revenues from any of these products and product candidates may be delayed. Significant clinical trial delays could also allow our competitors to bring products to market before we do, or shorten any periods during which we have the exclusive right to commercialize our products and product candidates. Moreover, we must obtain separate regulatory approvals in each jurisdiction where we want to market, and approval by one regulatory authority does not ensure approval by any other regulatory authority. As approval procedures can vary among countries and may change over time, this can require additional clinical testing, and the time required to obtain approval may differ. We can provide no assurances that such approval will be obtained on the timeline that we expect or at all. In addition, we anticipate submitting applications for approval of VYVGART in new indications, but can provide no assurances that such applications will be accepted or that we will receive approval on our anticipated timeline, or at all. If VYVGART or any new formulations of VYVGART are not approved in one or more jurisdictions including beyond the countries where VYVGART is approved, or if such approvals are significantly delayed, it could have a material adverse effect on our business. It is possible that none of our other existing product candidates or any product candidates we may seek to develop in the future will ever obtain regulatory approval in any other jurisdiction for any indication. Even if approval is obtained, the Relevant Regulatory Authorities or other comparable regulatory authorities may approve the product for fewer or more limited indications or patient sub-segments than requested and/or with a label that does not include the labeling claims necessary or desirable for the successful commercialization of that product. Further, the Relevant Regulatory Authorities or other comparable regulatory authorities may impose extensive and ongoing unique regulatory requirements, such as granting approval contingent on the performance of costly post-marketing clinical trials, including Phase 4 clinical trials, and surveillance to monitor the safety and efficacy of the product. 14 Table of Contents The costs of compliance with all Relevant Regulatory Authorities' and other applicable authorities' regulations, requirements or guidelines could be substantial, and failure to comply could result in sanctions, including fines, injunctions, civil penalties, denial of applications for marketing authorization of our products, delays, suspension or withdrawal of approvals, license revocation, seizures or recalls of products, operating restrictions and criminal prosecutions, any of which could significantly increase our and/or our collaborative partners’ costs or delay or prevent the development and commercialization of our product candidates. At this time, we cannot guarantee or know the exact nature, precise timing and detailed costs of the efforts that will be necessary to complete the remainder of the development of our research programs and product candidates. We are subject to privacy, cybersecurity and AI laws, regulation and potential enforcement. The failure to comply with these laws could harm our results, operations and/or financial conditions. Privacy laws, regulations and related enforcement are particularly relevant to our business as we collect, store and process personal data and in particular data of vulnerable groups such as patients, and sensitive information including health data as well as human biological samples. We also collaborate with third parties where we may seek to use data collected by third parties on our or their behalf, or we may seek to share data collected by us with such third parties to further our research or commercial initiatives. The GDPR imposes strict requirements, including access controls, impact assessment and safeguards on cross-border transfers of personal data and imposes substantial penalties in the event of non-compliance. We face uncertainty as to the exact interpretation of the requirements under the GDPR, and we may be unsuccessful in implementing all measures required by data protection authorities or courts. Any investigation by a data protection authority could result in fines and other penalties. The data privacy landscape is complex and fragmented. In the EU, national laws may impose stricter obligations than the GDPR, particularly for sensitive genetic, ethnic origin or race data, while regulations like the Directive 2002/58/EC of the European Parliament and of the Council of July 12, 2002 (as amended, the e-Privacy Directive) add further compliance risks. This trend expands globally, with evolving laws in countries such as the U.S., Japan, Canada and China. For example, China has passed a number of laws concerning data protection and the collection, use and transfer of personal data (including data considered to be relevant as Chinese human genetic resources), and restricting the transfer of this data outside of China. These evolving laws and regulations impose increasing restrictions on the processing of personal data, which may require us to modify our data collection or processing practices and to incur significant expenses associated with our compliance efforts. Moreover, in the current digital and regulatory landscape, privacy obligations are increasingly interconnected with broader cybersecurity laws and requirements, reflecting the close link between the protection of personal data and the security of information systems. Failure to comply with applicable cybersecurity frameworks and directives, including Directive (EU) 2022/2555 on Network and Information Security (NIS2), could result in significant legal, regulatory, and operational risks. In addition, inadequate cybersecurity and non-compliance with data protection laws and regulations increases the risk of personal data breaches, potentially resulting in regulatory sanctions, civil claims, reputational damage and loss of trust. Furthermore, our integration of AI solutions into certain of aspects our business, introduce a new layer of regulatory risk. Most significantly, Regulation (EU) 2024/1689 (AI Act) establishes the world’s first comprehensive legal framework for AI, impacting how we develop and deploy AI systems in the future. In particular, high-risk AI systems must comply with strict regulatory requirements to ensure safety, transparency, and fundamental rights protection. Non-compliance with the AI Act may result in significant penalties. As most provisions will take effect from August 2, 2026, we must continuously assess and adapt our compliance strategy to mitigate risks from this evolving legal landscape. If we violate existing laws and regulations or fail to comply with changing laws and regulations, we might be subject to fines, penalties and other adverse consequences, which could have a material adverse effect on our reputation, business, results of operations, cash flows or financial condition. Failure to comply with anti-corruption laws and regulations, anti-money laundering laws and regulations, economic or financial sanctions, trade embargoes and/or export control regulations and other laws governing our operations could have an adverse impact on our business, financial conditions and operations. We are or may become subject to various laws and regulations regarding anti-corruption, anti-money laundering, economic or financial sanctions, trade embargoes, investment restrictions, anti-fraud, other comprehensive prohibitions against transaction activity pursuant to anti-terrorism laws or export control laws and regulations issued by multiple jurisdictions. These include the UK Bribery Act 2010 and the U.S. Foreign Corrupt Practices Act of 1977, in each case, 15 Table of Contents as amended, as well as comparable laws and regulations in other countries in which we do business, including in the European Union and China, which prohibit, among other things, payments, offers, or promises made for the purpose of improperly influencing any act or decision of a foreign government official. In the UK, since September 1, 2025, it is an offense under the Economic Crime and Corporate Transparency Act 2023 for a large organization to fail to prevent certain fraudulent activities by an associated person (such as an employee, agent, or subsidiary), unless it can demonstrate that it had reasonable prevention procedures in place to prevent the fraudulent activity. The nature of our business means that we engage in significant interactions with foreign officials. Compliance with these laws and regulations in the U.S. and in foreign jurisdictions is complex, and may increase our cost of doing business internationally. We are also subject to economic and financial sanctions, trade embargoes, other comprehensive prohibitions against transaction activity pursuant to anti-terrorism laws and export control rules and regulations, including those imposed, administered or enforced by the UN Security Council, the, U.S., the UK, and the EU. Any change in export or import regulations, economic or financial sanctions regulations, trade embargo regulations or related legislation, shift in the enforcement or scope of existing regulations, or change in the countries, governments, persons or technologies targeted by such regulations, could decrease our ability to conduct our planned research and development activities and to manufacture, import, export or sell our products internationally, which could require us to expend additional resources to achieve our goals and adversely affect our business, financial conditions and operations. We have mechanisms in place to promote compliance with such rules and regulations. However, there can be no assurance that our policies and procedures will be followed at all times or will effectively detect and/or prevent violations of applicable compliance regimes by our employees, consultants, sub-contractors, agents and partners. In the event of non-compliance, we could be subject to substantial civil or criminal penalties, including sanctions against us, incarceration for responsible employees and managers, the possible loss of export or import privileges, debarment from participation in government contracting, reputational harm, and resulting loss of revenue and profits, which could have a material adverse impact on our business, financial conditions and operations. Our performance tracked by our Environmental, Social and Governance metrics is subject to risks and the outcomes may not achieve the anticipated benefits or align with new regulations and stakeholders’ expectations. There has been an increasing focus from stakeholders and regulators relating to environmental, social and governance (ESG) matters across all industries in recent years. The standards and stakeholder expectations continue to evolve, sometimes with contradictory expectations, and criteria to evaluate ESG practices may change rapidly. We are subject to evolving rules, including the European Union’s Corporate Sustainability Reporting Directive (CSRD) and ancillary European Union legislation. The SEC adopted rules in 2024 requiring enhanced climate-related disclosures, but after legal challenges, subsequently announced that it would end its defense of such climate disclosure rule. As a result, various U.S. states have enacted or proposed climate- and sustainability-related disclosure laws that may apply to companies doing business in those jurisdictions, such as California’s climate and carbon market disclosure laws, which would require in-scope companies to report on greenhouse gas emissions, climate-related financial risks, and the use of carbon offsets and emissions reduction claims relating to their operations or products. The future of the California climate disclosure laws is uncertain, as these laws are subject to ongoing litigation. In response to new ESG initiatives and regulations we may voluntarily elect, or be required, to adopt strategies, policies, or procedures related to ESG matters. Such efforts could divert management’s attention from central operational matters and cause us to expend significant capital and human resources. Moreover, increasingly, different stakeholder groups and regulators have divergent views, particularly in the U.S., on ESG matters, which increases the risk that any action or lack thereof with respect to sustainability or ESG matters will be perceived negatively by at least some stakeholders and regulators and adversely impact our business and reputation. The current sociopolitical landscape has led to rapid and unpredictable shifts in public sentiment, which has resulted in dynamics that increase the risk of reputational damage, boycotts and shifts in consumer behavior that could adversely affect our business and reputation. Reports could also lead to the disclosure of information that may have a negative impact on our operations and reputation which may lead to additional exposure. In addition, any required disclosures and measurements of ESG metrics are highly dependent on third-parties, such as our suppliers and CROs, that we do not control. Failure to accurately comply with any sustainability reporting obligations may result in enforcement actions, sanctions, fines and penalties, reputational harm or private litigation. We may become exposed to liability and substantial expenses in connection with environmental compliance or remediation activities. Our operations, including our research, development and testing, and our third-party manufacturers’ and suppliers’ operations, are subject to numerous environmental, health and safety laws and regulations and for which we may become liable. These laws and regulations govern, among other things, the controlled use, handling, release and disposal of and the maintenance of a registry for, hazardous materials and biological materials, laboratory procedures and exposure to 16 Table of Contents pathogens. We do not have control over our manufacturers’ or suppliers’ compliance with environmental, health and safety laws and regulations. If we or one of our CMOs or third-party distributors, manufacturers, suppliers, licensees or co-marketers fail to comply with such laws and regulations, such failure could result in substantial liability, fines, penalties or other sanctions and incur substantial expenses, and could also face significant reputational loss. We face a risk of environmental liability inherent in our current and historical activities, including liability relating to releases of our exposure to hazardous or biological materials. Furthermore, environmental, health and safety laws and regulations are becoming more stringent. Both us and our third-party manufacturers and suppliers may be required to incur substantial expenses in connection with future environmental compliance or remediation activities, in which case, our production and development efforts may be interrupted or delayed, and our financial condition and results of operations may be materially adversely affected. Risk Factors Related to argenx’s Financial Position We may not be able to be profitable or sustain net profitability in the future and may require additional financing to fund our operations. To be profitable or sustain net profitability in the future, we must continue to succeed in commercializing products that generate significant product net sales. Our future results of operations and profitability may fluctuate from period to period, and we will need to generate significant revenues to be profitable or sustain net profitability in the future. We may not be able to generate these revenues, and we may never achieve profitability on a sustained basis in the future. If we do not succeed in sustaining profitability or in funding our operations, we would not be able to use deferred tax assets against taxable profits which would result in a de-recognition of our deferred tax asset balance. In addition, we intend to continue to conduct research and development, preclinical testing, clinical trials and regulatory compliance activities as well as the continued commercialization of VYVGART and other products candidates, for current and future indications, and we intend to continue our efforts to expand our sales, marketing and distribution infrastructure. As a result, we anticipate that our operating expenses will increase as we execute on our strategic objectives and could increase more significantly if we experience delays or encounter issues relating thereto, including failed clinical trials, ambiguous clinical trial results, safety issues or other regulatory challenges. To finance our operations, particularly if we are unable to generate sufficient product net sales or otherwise control expenses, we may need to raise additional capital through a combination of public or private equity or debt financings or other sources, which may include collaborations with third parties. Our ability to raise additional funds on acceptable terms or at all will depend on financial, economic and market conditions and other factors, over which we may have no or limited control. If we cannot raise additional capital when needed on acceptable terms, we may be required to delay, reduce or terminate research and development programs; defer or forego commercialization of our products and product candidates (including for new indications); and limit expansion or otherwise fail to capitalize on business opportunities, any of which could have a material adverse effect on our business, financial condition and results of operations. Our assets, earnings and cash flows and the investment of our cash and cash equivalents may be subject to risks which may cause losses and affect the liquidity of these investments. We invest our cash in accordance with an established internal investment policy. Currently, substantially all of our available cash and cash equivalents and current financial assets are invested in either current accounts, savings accounts, term accounts or highly liquid money market funds. Any future investments may include term deposits, corporate bonds, commercial paper, certificates of deposit, government securities and money market funds in accordance with our cash investment policy. These investments may be subject to general credit, liquidity, market, inflation, foreign currency and interest rate risks and we may realize losses in the fair value of these investments or a complete loss of these investments. The aforementioned risks associated with our cash flows and investment portfolio may adversely affect our results of operations, liquidity and financial condition. Due to the international scope of our operations, our assets, earnings and cash flows are influenced by movements in exchange rates of several currencies, particularly the euro and Japanese Yen, versus the U.S. dollar. Our revenue from outside of the U.S. will increase as our products, whether commercialized by us or our business partners or our collaborators gain marketing approval in such jurisdictions. If the U.S. dollar weakens against a specific foreign currency, our revenues will increase, having a positive impact on net income, but our overall expenses will increase, having a negative impact on expenses. Conversely, if the U.S. dollar strengthens against a specific foreign currency, our revenues will decrease, having a negative impact on net income, but our overall expenses will decrease, having a positive impact on expenses. Continued volatility in foreign exchange rates is likely to impact our operating results and financial condition. 17 Table of Contents Risk Factors Related to argenx’s Business and Industry We may become exposed to costly and damaging liability claims. We are exposed to potential product liability and professional indemnity risks that are inherent in the research, development, manufacturing, marketing and use of pharmaceutical products and marketing of human therapeutic products. The current and future use of products and product candidates by us and our collaborators in clinical trials and the sale of any approved products may further expose us to liability claims. If any of our products or product candidates were to cause adverse side effects during clinical trials or after approval of the product candidate, we may be exposed to substantial liabilities. These claims might be made by patients who use the product, healthcare providers, pharmaceutical companies, physicians, payors, caregivers, investors, employees, government agencies, or our collaborators or others selling such products. Physicians and patients may not comply with any warnings that identify known potential adverse effects and patients who should not use our product candidates. Any claims against us, regardless of their merit, could be difficult and costly to defend and could materially adversely affect the market for our products and product candidates or any prospects for commercialization of our products and product candidates. Any such claims, regardless of their merit, could also adversely affect our reputation and the trust that physician and patients place in our products. Product liability risk in the EU will increase in the future once plaintiff-friendly reforms, such as Directive (EU) 2024/2853 (the new Product Liability Directive), take effect. The new Product Liability Directive introduces claimant- friendly changes. This includes, for instance, the expansion of the definition of “damage” (e.g. by including medically recognized psychological harm), creating rebuttable presumptions as to defect and causation to help claimants prove their case (e.g. if the claimant faces excessive difficulties to prove this due to scientific complexity) and abolishing minimum or maximum financial thresholds for claims. The new Product Liability Directive, like its predecessor, provides that claims shall expire if the injured person does not initiate proceedings within ten years after the defective product was placed on the market. However, it extends this long stop period (a statute of limitations) to 25 years if this is due to the latency of the underlying personal injury. Member States must transpose the Product Liability Directive into national law by December 2026. Regardless of the merits or eventual outcome, litigation or liability claims may result in: •decreased demand for our products due to negative public perception; •damage to our reputation; •withdrawal of clinical trial participants or difficulties in recruiting new clinical trial participants; •initiation of investigations by regulators; •costs to defend or settle the related litigation; •a diversion of management’s time and our resources; •substantial monetary awards to clinical trial participants or patients; •product recalls, withdrawals or labeling, marketing or promotional restrictions; •loss of revenues from product sales; and •the inability to successfully commercialize our product candidates, if approved. Although we maintain product liability insurance, we may not be able to maintain insurance coverage at a reasonable cost or to obtain adequate insurance coverage to satisfy any liability that may arise. Product liability claims could delay or prevent completion of our clinical development programs. In addition, claims made by patients, healthcare professionals or others might not be fully covered by product liability insurance and could result in investigations of the safety of our products or product candidates or may result in recalls. If a successful product liability claim or series of claims is brought against us for uninsured liabilities or in excess of insured liabilities, our assets may not be sufficient to cover such claims and our business, financial condition and results of operations would be adversely affected. In the ordinary course of business we may also face substantial, complex or extended litigation that could cause us to incur significant costs and distract our management. This is especially relevant for biopharmaceutical companies. Such litigation or proceedings could substantially increase our operating expenses and could adversely affect our business. 18 Table of Contents We may engage in strategic transactions, including acquisitions, collaborations, licenses or investments in other companies or technologies, and we may not realize the benefits of such transactions. We may enter into strategic transactions, including acquisitions, collaborations, licenses or investments for or in other companies or technologies that complement or augment our existing business and facilitate our access to new products, research projects or geographical areas. However, we may not be able to identify appropriate targets or enter into such transactions under satisfactory conditions. We may be unable to complete a proposed transaction if we or our shareholders are unable to obtain required regulatory approvals in the various jurisdictions in which we or a potential acquisition target or acquirer operate. In addition, we may need additional funding to finance these transactions including through issuances of public or private equity or convertible debt securities, which could be dilutive to our shareholders and ADS holders. Integrating any newly acquired companies, business, technologies or products could be expensive, time-consuming, and may never be successful. Integration efforts often take a significant amount of time, place a significant strain on managerial, operational and financial resources, result in loss of key personnel and could prove to be more difficult or expensive than we predict. The diversion of our management’s attention and any delay or difficulties encountered in connection with any future transactions we may consummate could result in the disruption of our ongoing business or inconsistencies in standards and controls that could negatively affect our ability to maintain third-party relationships. We cannot assure that we will achieve the expected synergies to justify any such transaction, which could have a material adverse effect on our business, financial condition, results of operations and future growth prospects and our investors’ ability to realize on their investment. Our business and operations could suffer in the event of system failures or unauthorized or inappropriate use of or access to our systems. We are increasingly dependent on our and our third-party partners’ information technology systems and infrastructure for our business. We collect, store and transmit sensitive information including intellectual property, proprietary business information, including highly sensitive clinical trial data, and personal data in connection with business operations. The secure maintenance of this information is critical to our operations and business strategy. Some of this information could be an attractive target of criminal attack or unauthorized access and use by third parties with a wide range of motives and expertise, including organized criminal groups, “hacktivists”, patient groups, disgruntled current or former employees and others. Cyber-attacks are of ever-increasing levels of sophistication, and despite our security measures, our information technology and infrastructure may be vulnerable to such attacks or may be breached, including due to employee error or malfeasance. In addition to these threats, we are subject to stringent cybersecurity laws, most notably NIS2 with respect to our activities in the European Union. As a company involved in the development and manufacturing of pharmaceutical and medicinal products, our operations could be brought within the scope of NIS2. This would require us to implement robust measures to secure our network and information systems. We are also subject to cybersecurity laws in other international jurisdictions in which we conduct our operations, such as the Cybersecurity Review Measures in China. Failure to comply with these cybersecurity standards could result in significant penalties. See ”Item 3.D. Risk Factors— Risk Factors Related to Other Government Regulations—We are subject to privacy, cybersecurity and AI laws, regulation and potential enforcement. The failure to comply with these laws could harm our results, operations and/or financial conditions.” Although we are making significant efforts to maintain the security and integrity of our information systems and the information systems of our third-party partners and are exploring various measures to manage the risk of a security breach or disruption, there can be no assurance that our security efforts and measures will be effective or that attempted security breaches or disruptions would not be successful or damaging. Despite the implementation of security measures, our internal computer systems and those of our third-party partners, contractors and consultants are vulnerable to damage or interruption from computer viruses, unauthorized or inappropriate access or use, natural disasters, pandemics, terrorism, war (including the ongoing conflict in Ukraine and conflict in the Middle East), and telecommunication and electrical failures. For example, the loss of pre-clinical trial data or data from completed or ongoing clinical trials for our product candidates could result in delays in our regulatory filings and development efforts, as well as delays in the commercialization of our products, and significantly increase our costs. To the extent that any disruption, security breach or unauthorized or inappropriate use or access to our systems were to result in a loss of or damage to our data, or inappropriate disclosure of confidential, personal or proprietary information, we could incur notification obligations to affected individuals and government agencies, liability, including potential lawsuits from patients, collaborators, employees, stockholders or other third parties and liability under foreign, federal and state laws that protect the privacy and security of personal data, and the development and potential commercialization of our product candidates could be delayed. Disruptions in the our and our third-party partners’ information technology systems could adversely affect our business operations and harm our competitive position. 19 Table of Contents Not all of our contracts contain limitations of liability, and even where they do, there can be no assurance that limitations of liability in our contracts are sufficient to protect us from liabilities, damages or claims related to our data privacy and security obligations. We cannot be sure that our insurance coverage will be adequate or sufficient to protect us from or to mitigate liabilities arising out of our privacy and security practices. Risk Factors Related to argenx’s Intellectual Property We may be unable to adequately maintain, enforce or protect our intellectual property rights in products, product candidates and platform technologies which could adversely affect our ability to maximize the value for patients in our marketed products and product candidates. Our commercial success depends in part on obtaining and maintaining patents and other forms of intellectual property rights for our products, product candidates and platform technologies. Failure to obtain, maintain, enforce, protect, or extend adequate patent and other intellectual property rights, which can be challenging and costly, could adversely affect our ability to develop and market our products and product candidates and reduce any competitive advantage we may have. We cannot be certain that patents will be issued or granted with respect to applications that are currently pending and we may not be the first to file patent applications related to our product candidates and products. The scope of patent protection that the European Patent Office and the USPTO will grant with respect to products in our product pipeline is uncertain and may vary. It is possible that the European Patent Office and USPTO will not allow broad claims that cover molecules closely related to our products and product candidates as well as the specific molecule, and competitors may be free to market substantially similar molecules if granted approval, thereby reducing our market potential. We and our current or future licensors, licensees or collaboration partners may not be able to prepare, file, prosecute and maintain all necessary or desirable patent applications at a reasonable cost or in a timely manner. Our current and future licensors’, licensees’ or collaboration partners’ ability to ensure the issuance, scope, validity, enforceability and commercial value of technology licenses is uncertain and we may need to rely on them to obtain costly additional IP licenses. Additionally, such parties may not fully comply with applicable patent rules or laws, which could result in loss of patent rights, or such parties may disagree with us as to the strategy for prosecution, maintenance or enforcement of any such patent rights. Filing, prosecuting, and defending patents on product candidates in all jurisdictions throughout the world would be prohibitively expensive and the laws of certain jurisdictions may not protect our rights to the same extent as the laws of the U.S., UK or EU. We may face difficulties in enforcing patent rights in the future, including in certain jurisdictions where we have not yet filed patent applications. Competitors may use our and our licensors’ or collaboration partners’ technologies in jurisdictions where we have not obtained patent protection, or where broad research exemptions are available, to develop their own products. Third parties may export otherwise infringing products to territories where we, our licensors or collaboration partners have patent protection, but where enforcement is not as strong as that in the U.S., UK and the EU. In such cases, we would have little effective recourse to prevent such products from competing with ours. In addition, some countries have compulsory licensing laws under which a patent owner may be compelled to grant licenses to third parties, and other countries limit the enforceability of patents against government agencies or government contractors. In these countries, the patent owner may have limited remedies, which could materially diminish the value of such patent. Intellectual property litigation could lead to substantial resource diversion or issued patents could be found invalid, not infringed, or unenforceable if challenged in the applicable patent office or court. Our patents may remain open to invalidity challenges after allowance or grant, whereby third parties can challenge the scope or validity of such granted patent. In the course of such proceedings, we may be compelled to limit the scope of patent claims thus challenged or may lose the claims altogether. We may elect to initiate adversarial proceedings in order to enforce or defend any intellectual property rights owned by or licensed to us, or to determine or challenge the scope or validity of intellectual property rights of third parties to protect our competitive position. We may need to divert substantial time and resources to the enforcement and protection of our or our collaboration partners’ intellectual property rights. In addition, the outcomes of any proceedings could be uncertain and any remedies or damages awarded may not be meaningful. An adverse ruling of non-infringement, limiting claim scope, or invalidating one or more of our issued patents could allow third parties to commercialize our products after the expiration of our market exclusivity or use our platform technologies to compete directly with us, without payment to us. 20 Table of Contents In many jurisdictions (including the Unified Patent Court), an action to enforce a patent may not be brought until immediately before, or even after, the infringing product of a competitor has been launched in the market. In these jurisdictions, infringement rulings and injunctions (even in preliminary injunction proceedings) are often issued only after the competing product has already been launched and potentially impaired the competitive advantage on the market. We may be subject to claims challenging the inventorship or ownership of our intellectual property or be required to make additional payments to secure intellectual property from collaborators. Many of our consultants and employees, including in the senior management team (consisting of our CEO and senior personnel reporting directly to the CEO) (Senior Management Team), were previously employed at other competing or potentially competing biotechnology or pharmaceutical companies and some have executed proprietary rights, non- disclosure and non-competition agreements in connection with such previous employment. Although we take measures to ensure third parties, consultants and employees do not use such proprietary information in their work for us, we may be subject to claims that we or these consultants and employees have improperly used or disclosed confidential information or intellectual property of their former employer. Additionally, many of our collaborators do not commit to assigning all intellectual property arising out of our collaborations to us and, instead, grant us options to acquire intellectual property or commit to making such intellectual property available to us at a fair price. As such, we may be required to make additional payments to secure valuable intellectual property rights under our existing collaborations or become subject to inventorship disputes. In addition, although we take steps to ensure that our collaborators do not use our intellectual property rights other than for the purposes of our collaboration, there may be instances where former or current collaborators or other third parties nevertheless apply for or obtain patent protection for inventions to which we believe we have rights, in whole or in part. In such cases, we may elect to assert our ownership of such intellectual property. There is no guarantee that we will be successful in asserting such claims. In addition, while it is our policy to require our employees and contractors who may be involved in the development of intellectual property to execute agreements assigning such intellectual property to us, we may be unsuccessful in ensuring effective assignment of intellectual property under such agreements. Our assignment agreements may not be self-executing, or may be breached, and we may be forced to bring or defend against claims to assert ownership of such intellectual property. There is no guarantee we will be successful in pursuing such claims, which could result in us paying monetary damages or losing valuable personnel or intellectual property rights. Third-party intellectual property rights could adversely affect our ability to commercialize our products and product candidates. Our revenue generated may suffer if valid and enforceable third-party intellectual property rights cover our products, product candidates, manufacturing processes, or those of our partners. In such cases, our freedom to develop or commercialize products or product candidates may require obtaining a license, designing around third party intellectual property rights with significant time and materials costs, or invalidating the third party rights. If our products are found to infringe a valid and enforceable patent claim, we and our partners could be prevented from continuing to develop or commercialize the affected product without an appropriate license, which may be costly or unavailable on commercially reasonable terms, if at all. Similarly, other companies may have filed patent applications or have patents directed toward molecules and/or uses of those molecules that modulate similar targets modulated by our products and we may not be aware of unpublished pending patent applications or patent applications that are amended to cover our products or platform technologies. Even if we or our partners can obtain the appropriate license, it may be non-exclusive, thereby providing third parties with the opportunity to access the same licensed technology. If the breadth and scope of protection provided by our or our partners’ patents, licensed patents, or patent applications is threatened or limited, it could dissuade companies from future collaborations with us to license, develop, or commercialize products and product candidates which would have an adverse effect on our business position. Furthermore, because of the substantial amount of discovery required in connection with intellectual property litigation, some of our confidential information could be disclosed in any such proceedings. We may not be successful in obtaining or maintaining necessary rights to our products and product candidates through acquisitions and in-licenses. We may be unable to acquire or in-license third-party intellectual property rights necessary or useful for development or commercialization of our product, product candidates or technology. We sometimes collaborate with U.S. and non-U.S. 21 Table of Contents academic institutions and typically receive an option to negotiate a license to the institution’s proprietary interest in any collaboration technology. However, we may be unable to successfully negotiate such license and the institution may offer such intellectual property rights to third parties thereby devaluing our exclusive rights to pursue the applicable program. In addition, our competitor companies may be unwilling to license desirable or necessary intellectual property rights to us, or we may be otherwise unable to license or acquire other third party intellectual property rights on commercially reasonable terms which could negatively impact current development or hinder our ability to pursue development of new programs. Under our existing licenses, failure to comply with our obligations thereunder could result in termination of such licenses, thereby limiting our ability to develop and commercialize products covered by such licensed technology. Moreover, despite our efforts to comply with our contractual obligations, our licensors could conclude we have materially breached any such agreement and we could incur significant costs and disruption to our business defending against any breach alleged by the licensor. Moreover, several of our existing license agreements are sub-licenses from third parties. We have little control if our licensors fail to comply with their obligations under their upstream license agreements, whereby the original third-party licensor may have the right to terminate the original license and possibly our sub-license. In such cases, we may not be able to procure a direct license covering such intellectual property possibly materially affecting our ability to develop and commercialize certain products and product candidates. If our brand protection strategies, including the filing, prosecution and enforcement of trademarks and trade names, are not adequately executed, we may not be able to build name recognition for approved products in our markets of interest in line with our strategic priorities. Third parties may seek to oppose, attempt to cancel our trademark applications, or challenge, infringe or circumvent our registered and unregistered trademarks, including through counterfeiting of our products. In the event that our trademarks are successfully challenged, we may not be able to use these trademarks to continue to effectively market our branded products and could be forced to rebrand them, which could result in loss of their brand recognition or require us to devote resources to develop new brand profiles. Such efforts could also hinder our efforts to commit to and deliver on strategic internal initiatives. If we attempt to enforce our trademarks or assert trademark infringement claims, a court may determine that our trademarks are invalid or unenforceable or that the party against whom we have asserted trademark infringement has superior rights with respect to such marks. If we are unable to establish name recognition and adequately protect and enforce our trademark portfolio, we may not be able to compete effectively in the market or build brand recognition for new products globally. We may not be able to obtain protection under the U.S. Drug Price Competition and Patent Term Restoration Act of 1984 (Hatch-Waxman Act) and similar non-U.S. legislation for extending the term of patents covering each of our products and product candidates. Depending upon the timing, duration and conditions of FDA marketing approval of our product candidates, one or more of our U.S. patents may be eligible for limited patent term extension under the Hatch-Waxman Act and similar legislation in the EU and the Asia Pacific region. However, the patent term extension under the Hatch Waxman Act cannot extend the remaining term of a patent beyond a total of 14 years from the date of product approval, and only one patent applicable to an approved drug may be extended. If we are unable to obtain patent term extension, the term of any such extension is less than we request, or the statutes governing patent term extension are amended to reduce the term of such extensions, our patent exclusivity for that product will be shortened and our competitors may obtain approval to market competing products sooner than we expect. Changes in patent laws or patent jurisprudence could diminish the value of patents in general thereby impairing our ability to protect our products. Changes in patent law across jurisdictions, or changes in any relevant government’s enforcement procedure may weaken our ability to obtain new patents or to enforce rights in our owned and licensed patents. For example, the U.S. Supreme Court has ruled on several patent cases in recent years, either narrowing the scope of patent protection available in certain circumstances or weakening the rights of patent owners in certain situations. Relatedly, the U.S. Congress is considering multiple draft bills that, if passed, may have a significant impact on U.S. patent laws. Any such changes by 22 Table of Contents the U.S. Congress or U.S. courts and the relevant law-making bodies in other countries may materially affect our patents or patent applications and we cannot predict the effects of future changes in patent law. We may be unable to protect the confidentiality of our trade secrets and their disclosure to competitors, harming our market position. In addition to patent protection, we rely on trade secret protection to preserve the value of our proprietary information supporting our business model. We take balanced measures to preserve the commercial value of our trade secrets and prevent their misappropriation. However,despite these measures, which include segregation of key files, requiring our licensors, collaborators, suppliers, consultants and advisors to execute confidentiality agreements, we cannot fully protect against willful or inadvertent unauthorized disclosure of our trade secrets. Trade secret enforcement proceedings can be unpredictable and vary across geographies and we may not be able to secure adequate legal or equitable remedies to prevent lost value in our misappropriated trade secrets. Any misappropriation and use, whether willful or inadvertent, could result in lost value to the company and enable our competitors to duplicate or build upon our technology. Risk Factors Related to argenx’s Organization and Operations Our future growth and ability to compete depends on maintaining our culture, retaining our key personnel and recruiting additional qualified personnel. We believe that our corporate culture has been, and will continue to be a key contributor to our success. However, as we implement more complex organizational structures, and increase our headcount to support the growth in our business, our ability to foster our key values - innovation, co-creation, empowerment, excellence and humility that we believe are important to support our growth - may be impacted. We may find it increasingly difficult to maintain the beneficial aspects of our corporate culture, which could similarly negatively impact our ability to attract, retain and motivate qualified employees and our future success. As a global organization in a highly competitive and specialized industry, our success also depends upon the continued contributions of our key management, scientific, medical and technical personnel, many of whom have been instrumental for us and have substantial experience with our product and related technologies. These key management individuals include the members of the Board of Directors and Senior Management Team. Difficulties in recruiting or the loss of key managers, scientific, medical or technical personnel could delay our research and development activities. In addition, it may be difficult to attract and retain highly qualified management, scientific and medical personnel, particularly if we expand into fields that will require additional skills. In addition, future leadership transitions and management changes may cause uncertainty in, or a disruption to, our business, and may increase the likelihood of senior management or other employee turnover. We are currently undergoing a leadership transition, as in early January 2026, we announced that Karen Massey, our current COO, will transition to the role of CEO and Executive Director and Tim Van Hauwermeiren, our current CEO, will transition to the role of Non-Executive Director and Chairperson of the Board of Directors. Both transitions are subject to shareholder approval at the 2026 General Meeting. Any failure to ensure an effective transition or any future management changes could adversely affect our business, and we cannot predict the likelihood, timing or effect of future transitions among our executive leadership. As a Dutch company listed on Euronext Brussels and Nasdaq, our remuneration practices and policies may be limited by local governance rules or shareholder guidance for EU companies. Such limitations may make it more difficult to successfully compete for key talent in a number of markets with differing remuneration practices and policies compared to our competitors. For example, the Dutch Corporate Governance Code 2025 (DCGC) places certain limitations on the ability to grant equity incentives to Non-Executive Directors, while Belgian law requires Non-Executive Directors to receive part of their remuneration in the forms of shares, but not stock options. The DCGC also places limitations on amount of severance payment permitted in the event of dismissal. Many other biotechnology and pharmaceutical companies and academic institutions that we compete against for qualified personnel have greater financial and other resources, different risk profiles and a longer history in the industry than we do. Additionally, inflationary pressures and a tight labor market for skilled workers may increase compensation expectations, requiring us to raise operating costs in order to attract and retain employees. Therefore, we might not be able to attract or retain these key persons or other employees on conditions that are economically acceptable. Global geo- and socio-political threats and macro-economic uncertainty and other unforeseen political crises could materially and adversely affect our business and financial performance. Many geo- and socio-political threats and macro-economic uncertainties are outside of our control and could adversely affect consumer confidence and disposable income levels, increase difficulty in forecasting our financial results and have other impacts on our business and financial performance. Such geo- and socio-political threats could also result in 23 Table of Contents volatility in stock markets in general, causing our stock to have extreme price and volume fluctuations unrelated to our business and financial performance. Such geo- and socio-political threats and uncertainties include: •general economic and market conditions, including government shutdowns, including the U.S. government shutdown, instability resulting from inflationary pressures, and increasing interest rates; •geopolitical events, including natural disasters, public health emergencies, acts of war, and terrorism; •economic and financial sanctions, trade embargoes, import and export regulations, tariffs, customs, and inbound and outbound investment restrictions; •restrictions, changes in trade agreements, trade barriers or other restrictions on foreign trade, and changes in trade regulations and restrictions, including between the U.S. and other countries; •global or regional economic conditions that impact companies and customers with which we do business; •political or social unrest, economic instability, repression, or human rights issues; •disruptions in supply chains; •risks related to other government regulation or required compliance with local laws; •consumer and commercial credit availability, unemployment, and consumer debt levels; and •local licensing and reporting obligations. Due to our international operations and the fact that we run clinical trials across multiple jurisdictions, geopolitical conflicts and related sanctions may, in certain circumstances, impact our ability to conduct or complete clinical trials in the affected regions. For example, General License 6D issued by the U.S. Department of the Treasury’s Office of Foreign Assets Control currently authorizes certain clinical trial and medical research activities that would otherwise be restricted by U.S. sanctions targeting Russia, the scope, availability, or duration of such authorizations may change. We also perform development activities in a number of countries exposed to geopolitical risk and if conflicts in those countries were to escalate further and impact neighboring countries, it could impact our development activities in those countries. Changes in U.S.-Mainland China relations, including tariffs, export controls, economic and financial sanctions, and other regulations may adversely impact our collaboration with Zai Lab in Mainland China, Hong Kong, Taiwan and Macau (together, Greater China). The U.S. government has taken steps and continues to take steps with regard to U.S.-Mainland China relations that will impact companies with connections to the U.S. or Mainland China, including by imposing tariffs affecting certain products manufactured in Mainland China, imposing economic and financial sanctions on certain individuals and entities in the Mainland China, and issuing statements indicating enhanced review of companies with significant Mainland China-based operations. The U.S. government has also passed laws, including the BIOSECURE Act, which was signed into law on December 18, 2025, that could limit or restrict our ability to purchase products or services from, or otherwise collaborate with, certain Chinese biotechnology companies without losing our ability to contract with or receive funding from the U.S. government. Such restrictions could have an adverse impact on our operations. Several countries are considering or have implemented tariffs, trade barriers or restrictions, as well as other measures impacting cross-border commerce, which could negatively affect our business, financial conditions and results of operations, including by disrupting our research and development activities, affecting our suppliers and negatively impacting our supply chain, impacting our ability to sell our products outside of the United States and negatively impacting our revenues from product sales or our cost of goods sold. The U.S. federal government has implemented tariffs on certain foreign goods and may implement additional or revised tariffs in the future. Such actions could give rise to retaliatory tariffs imposed by foreign governments and an escalation of trade measures by the U.S. and impacted countries. Developments with regard to the timing and manner in which tariffs will be implemented; the amount, scope, and nature of tariffs; the countries subject to new or additional tariffs imposed by the U.S.; tariffs imposed by other countries on goods imported from the U.S.; and other wide-ranging retaliatory measures are rapidly evolving and may change unexpectedly at any time. For example, the U.S. President has repeatedly announced plans to impose 100% tariffs on imported branded or patented pharmaceuticals, unless the importing company is building U.S. manufacturing capacity. It is not yet clear whether these tariffs would apply to the importation of active pharmaceutical ingredients and 24 Table of Contents possibly bulk drug products that are intended for use in clinical trials and not for commercial sale, which could increase the costs of materials for our clinical trials. Any direct tariffs, if imposed on pharmaceutical products, may result in increased costs for raw materials and contract manufacturing services, reduced ability to source critical CMOs, and a delay in our development timelines. Although on February 20, 2026, the U.S. Supreme Court struck down certain tariffs imposed by the Trump Administration pursuant to the International Emergency Economic Powers Act, the Trump Administration responded by announcing new tariffs pursuant to another statute. Other countries may, in turn, retaliate with new tariffs against US exports. These events increase the uncertainty and the risks we face resulting from tariffs described above. Any new legislation, executive orders, tariffs, export controls, economic and financial sanctions, trade embargoes and/or other regulations that may be implemented, any unfavorable government policies on international trade, including tariffs and export controls, the renegotiation of existing trade agreements, any increased scrutiny on companies with significant Mainland China-based operations, and any retaliatory actions taken by the U.S., EU, Chinese or other governments due to trade tensions could have an adverse effect on our business, including the development and commercialization of products containing argenx-licensed material. Further, general political uncertainty may have an adverse impact on our business, financial condition and results of operations. We face risks related to natural disasters and public health issues, that could negatively affect our business and financial condition. Our business could be adversely impacted by the effects of catastrophic global events including natural disasters such as earthquakes, fires, hurricanes, tornados, floods or significant power outages and public health crises. For example, the manufacturing of all of our products and product candidates requires using cells which are stored in a cell bank. We have one master cell bank for each product manufactured in accordance with cGMPs. However, it is possible that we could lose multiple cell banks and have our manufacturing significantly impacted by the need to replace these cell banks, which could materially adversely affect our business, prospects, financial condition and results of operations. Public health issues could also negatively affect our business and financial condition. We operate and conduct our clinical trials globally. We cannot presently predict the scope and severity of any potential future business shutdowns or disruptions as a result of public health issues. If we or any of the third parties with whom we engage, including the suppliers, contract manufacturers, clinical trial sites, regulators and other third parties, were to experience shutdowns, quarantines, or other business disruptions due to natural disasters or global public health issues, it may impair our or our third-party partners’ ability to initiate clinical trials and recruit and retain patients, particularly if quarantine or travel restrictions impede healthcare provider or patient movement, impact the usability of the data due to treatment interruptions and require protocol amendments. In addition, regulatory authorities may restrict their operations or be delayed in their operations during a pandemic, the outbreak of new variants or other public health issues, including further to travel restrictions which could adversely affect our ability to obtain regulatory approval for and to commercialize our products and product candidates and have a material adverse effect on our business and financial results. We are exposed globally to unanticipated changes in tax laws and regulations, adjustments to our tax provisions, exposure to additional tax liabilities, or adjustments of our tax assets. As a company active in research and development, we have benefited from certain research and development tax incentives including tax credits and a payroll withholding tax exemption. We also expect to benefit from the Belgian innovation income deduction. The determination of our provision for income taxes and other tax liabilities requires judgment, including the adoption of certain accounting policies and our determination of whether our deferred tax assets are, and will remain, fully available in future periods. We cannot guarantee that our interpretation of applicable tax laws (including with respect to our eligibility for, or our calculation of, tax incentives such as the Belgian R&D tax credit, the Belgian payroll withholding tax exemption for R&D personnel, the Belgian innovation income deduction and similar tax incentives in other jurisdictions in which we have material operations or sales), our transfer pricing policies or our organizational and operational structure will not be questioned by the relevant tax authorities, or that the relevant tax laws and regulations, or the interpretation thereof, including through tax rulings, will not be subject to change. Our effective tax rates could be adversely affected, now or in the future, by changes in tax laws, treaties and regulations or the interpretation thereof by the relevant tax authorities in countries where we have material operations. A successful challenge to tax positions in Belgium or other country where we have material operations may lead to adjustments in the amounts recorded in our financial statements and could have a significant impact on our effective tax rate and on our deferred tax assets. An increase of the effective tax rates could have an adverse effect on our business, financial position, results of operations and cash flows. In case of a change of control, we could be exposed to the risk of losing any unused tax credit and innovation income deduction. Furthermore, if any legislator decides to eliminate, or change the conditions for claiming such tax incentives, 25 Table of Contents or reduce the scope or the rate of such incentives, any of which it could decide to do at any time, our results of operations could be adversely affected including through the de-recognition of deferred tax assets. We may encounter difficulties efficiently managing our growth and our increasing development, regulatory, and sales and marketing capabilities, which could disrupt our operations. We have grown, and expect to continue to grow globally, significantly in the number of employees and scope of operations over recent years, particularly in the areas of drug research, drug development, regulatory affairs, and sales and marketing. To manage our anticipated future growth and support our expanding global footprint, we must continue to enhance our managerial, operational and financial systems, expand our facilities and recruit and train additional qualified personnel and build the internal infrastructure necessary. Any inability to manage growth effectively could delay the execution of our strategic objectives or disrupt our operations, which in turn could materially harm our business and prospects. In particular, our planned international expansion subjects us to a number of risks, including risks following complexities in monitoring and coordinating research and development, marketing, supply chain and other operations in a large number of jurisdictions, risks related to laws, regulations and policies, including those implemented following changes in political leadership and trade, risks related to varying standards and practices in the legal, regulatory and business cultures in which we operate, risks related to capital and exchange controls, cross-border taxes and tariffs, cross-border data transfer restrictions, and complex sanctions regimes in various countries such as the U.S., the EU and other jurisdictions, violations of which could lead to fines or other penalties, risks related to geopolitical and local political instability and uncertain business environments and risks related to complexities associated with managing local personnel and preventing misconduct by local third-party partners. The application of laws and regulations impacting global business operations is often unclear and may at times conflict. Compliance with these laws and regulations may involve significant costs or require changes in our business practices that result in reduced revenue and profitability. Non-compliance could also result in fines, damages, criminal sanctions, prohibited business conduct, and damage to our reputation. Risk Factors Related to the ADSs Holders of our ADSs have fewer rights than our ordinary shareholders. Except as described in this Annual Report or any deposit agreements, holders of ADSs are not treated as our shareholders unless they withdraw the ordinary shares underlying their ADSs in accordance with the deposit agreement and applicable laws and regulations. The depositary, or its nominee, is the holder of the ordinary shares underlying the ADSs. ADSs are transferable on the books of the depositary. The depositary may refuse to deliver, transfer or register transfers of ADSs. Temporary delays in the cancellation of ADSs and withdrawal of the underlying ordinary shares may arise. In addition, ADS holders may not be able to cancel their ADSs and withdraw the underlying ordinary shares when they owe money for fees, taxes and similar charges and when it is necessary to prohibit withdrawals in order to comply with any laws or governmental regulations that apply to ADSs or to the withdrawal of ordinary shares or other deposited securities. Holders of ADSs may vote them in person or by proxy in accordance with applicable laws and regulations and our articles of association (Articles of Association). We cannot guarantee that holders of ADSs will receive the voting materials in time to ensure that they can instruct the depositary to vote the ordinary shares underlying their ADSs. Holders of our ADSs may not be able to exercise their right to give voting instructions or to vote in person or by proxy and they may not have any recourse against the depositary or us if their ordinary shares are not voted as they have requested or if their shares cannot be voted. The price of our ADSs may be volatile and may fluctuate due to factors beyond our control. An active public trading market may not be sustained. The stock markets in general, and biopharmaceutical companies in particular, have experienced extreme price and volume fluctuations that have often been unrelated or disproportionate to the operating performance of these companies. The trading price of our ADSs depends on a number of factors, including those described elsewhere in this “Risk Factors” section, many of which are beyond our control and may not be related to our operating performance, which may limit or prevent investors from readily selling their ADSs or ordinary shares and may otherwise negatively affect the liquidity of our ADSs and ordinary shares. We provide guidance regarding our cash and expenses, which are inherently uncertain. Any guidance that we provide may not always be accurate or may vary. If we fail to meet our guidance, or if we have to revise such guidance, the price of our ADSs or ordinary shares could decline. Sales of a substantial number of ADSs or our ordinary shares in the public market, or the perception that these sales might occur, could depress the 26 Table of Contents market price of ADSs or our ordinary shares and could impair the market price of our securities or our ability to raise capital through the sale of additional equity securities. In addition, an active public trading market for our ADSs may not be sustained. Further, fluctuations in exchange rates may also impact the price of our ADSs and ordinary shares which may result in heavy trading by investors seeking to exploit such differences, or impact the proceeds holders receive. If securities or industry analysts cease coverage of us, or publish inaccurate or unfavorable research about our business, the price of our ADSs or ordinary shares and our trading volume could decline. The trading market for the ADSs and ordinary shares depends in part on the research and reports that securities or industry analysts publish about us or our business. We do not have control over these analysts. If no or too few securities or industry analysts cover us, the trading price of our ADSs and ordinary shares would likely be negatively affected. If one or more of the analysts who cover us downgrade our ADSs or ordinary shares or publish inaccurate or unfavorable research about our business, the price of our ADSs or ordinary shares would likely decline. If we fail to maintain an effective system of disclosure controls and internal control over financial reporting, our ability to comply with applicable regulations could be impaired, and the trading price of our ADSs may be negatively impacted. We are required to comply with various corporate governance and financial requirements under the Sarbanes-Oxley Act of 2002, the Dodd-Frank Wall Street Reform and Consumer Protection Act, the listing rules of the Nasdaq Global Market (the Nasdaq Listing Rules) and requirements, and other applicable securities rules and regulations. We are required to furnish a report by management on, among other things, the effectiveness of our internal control over financial reporting and an attestation report on internal control over financial reporting issued by our independent registered public accounting firm. Undetected material weaknesses in our internal controls could lead to financial statement restatements and require us to incur the expense of remediation. Moreover, any failure to maintain internal control over financial reporting or any material weaknesses or significant deficiency thereover, could result in a loss of investors’ in the accuracy, completeness and reliability of our financial statements, subject us to sanctions or investigations, or negatively impact the trading price of our ADSs or ordinary shares. Risk Factors Related to being a Foreign Private Issuer or a Dutch Company The risks in this subsection that relate to our status as a foreign private issuer will change if we lose our status as a foreign private issuer under U.S. law. We are a Dutch European public company with limited liability. The rights of our shareholders may be different from the rights of shareholders in companies governed by the laws of U.S. jurisdictions. We are a Dutch European public company with limited liability (Societas Europeae). The rights of shareholders and the responsibilities of members of our Board of Directors may be different from the rights and obligations of shareholders in companies governed by the laws of U.S. jurisdictions. As a result of these differences between Dutch corporate law and our Articles of Association, on the one hand, and the U.S. federal and state laws, on the other hand, in certain instances, our shareholders and holders of our ADSs could receive less protection than they would as shareholders or ADS holders of a listed U.S. company. For example, provisions of our Articles of Association may make it more difficult for a third party to acquire control of us or effect a change in our Board of Directors. We have adopted several provisions that may have the effect of making a takeover of our Company more difficult or less attractive. These provisions could discourage potential takeover attempts that other shareholders may consider to be in their best interest and could adversely affect the market price of our securities. Holders of our ordinary shares outside the Netherlands, and holders of ADSs may not be able to exercise pre-emptive rights or preferential subscription rights, respectively. In the event of an increase in our share capital, holders of our ordinary shares are generally entitled under Dutch law to full pre-emptive rights, unless these rights are excluded either by a resolution of the shareholders at a General Meeting, or by a resolution of the Board of Directors (if the Board of Directors has been designated by the shareholders at a General Meeting for this purpose). However, making pre-emptive rights available to holders of ordinary shares or ADSs representing ordinary shares also requires compliance with applicable securities laws in the jurisdictions where holders of those securities are located, 27 Table of Contents which we may be unable or unwilling to do. In particular, holders of ordinary shares or ADSs located in the U.S. would not be able to participate in a pre-emptive rights offering unless we registered the securities to which the rights relate under the U.S. Securities Act of 1933, as amended (Securities Act) or an exemption from the registration requirements. In addition, ADS holders would not be able to participate in a pre-emptive rights offering unless we made arrangements with the depositary to extend that offering to holders of ADSs, which we are not required to do. Claims of U.S. civil liabilities may not be enforceable against us or the members of our Senior Management Team and our Board of Directors. A significant amount of our assets are located outside the U.S. The majority of the members of our Senior Management Team and our directors are not U.S. residents and we do not have significant assets in the U.S. As a result, it may not be possible, or more difficult, for investors to enforce against them or us in U.S. courts, including judgments predicated upon the civil liability provisions of the U.S. federal securities laws. There are no treaties between the U.S. with either the Netherlands or Belgium providing for the reciprocal recognition and enforcement of judgments, other than arbitration awards, in civil and commercial matters. Consequently, a final judgment for payment given by a court in the U.S. based on civil liability, whether or not predicated solely upon U.S. securities laws, would not automatically be recognized or enforceable in the Netherlands or in Belgium unless the underlying claim was re-litigated before a Dutch or Belgian court of competent jurisdiction. This will depend on the applicable Dutch or Belgian national rules. In addition, there is doubt as to whether a Dutch or Belgian court would impose civil liability on us or the members of our management or of our Board of Directors in an original action predicated solely upon the U.S. federal securities laws brought in a court of competent jurisdiction against us, our management or directors. As a foreign private issuer, we are exempt from various rules and regulations that a U.S. domestic public company would be required to follow, including those requirements under U.S. securities laws and Nasdaq listing standards. As a “foreign private issuer” defined in the SEC’s rules and regulations, we are not subject to all of the disclosure and corporate governance requirements applicable to companies organized within the United States. For example, we are exempt from certain provisions of the U.S. Securities Exchange Act of 1934, as amended (Exchange Act), that are applicable to U.S. domestic public companies. In addition, our executive officers, directors and principal shareholders are exempt from the short-swing profit and recovery provisions contained in Section 16(b) of the Exchange Act. We are subject to Dutch laws and regulations with regard to such matters. While we furnish quarterly unaudited financial information to the SEC on Form 6-K, the information we furnish to the SEC is less extensive and less timely compared to that required to be filed with the SEC by U.S. domestic issuers. As a foreign private issuer listed on Nasdaq, we are subject to corporate governance listing standards. However, we are permitted to rely on home country governance requirements and certain exemptions thereunder. Certain of our corporate governance practices may differ significantly from the Nasdaq corporate governance listing standards. These practices may afford less protection to shareholders than they would enjoy if we complied fully with corporate governance listing standards. As a Dutch public company with limited liability, we are not obligated to, and do not comply with, all the best practice provisions of the DCGC, which may affect shareholders’ rights. We are required to disclose in our annual report, filed in the Netherlands, whether we comply with the provisions of the DCGC. If we do not comply with the provisions of the DCGC, we must list the reasons for any deviation from the DCGC in our annual report filed in the Netherlands. We may lose our foreign private issuer status which would then require us to comply with the Exchange Act’s domestic reporting regime and cause us to incur significant legal, accounting and other expenses. In order to maintain our current status as a foreign private issuer, either (a) a majority of our ordinary shares must be either directly or indirectly owned of record by non-residents of the U.S. or (b) none of the following conditions may be true: (i) a majority of our executive officers or directors are U.S. citizens or residents, (ii) more than 50% of our assets are located in the U.S. and (iii) our business is administered principally in the U.S. As of February 19, 2025, we believe at least 50% of our outstanding ordinary shares were held by U.S. residents (assuming that all our ordinary shares represented by ADSs were held by residents of the U.S.). In June 2025, the SEC issued a concept release soliciting public comment on potential changes to the definition of a foreign private issuer. This release is the first review of the foreign private issuer framework since 2008, and the SEC is considering revisions that could significantly impact which foreign companies qualify for the more accommodative U.S. reporting, corporate governance requirements afforded to foreign private issuers, as well as the lack of Section 16(b) liability for certain FPI officers, directors and shareholders. The SEC may revise the requirements to qualify as a foreign private issuer in a way that changes our status as a foreign private issuer and results in us qualifying as a U.S. domestic issuer. This could cause us to have to comply with regulations applicable to U.S. domestic issuers in a very compressed timeframe. The regulatory and compliance costs to us as a U.S. domestic issuer may be significantly higher than those 28 Table of Contents we incur as a foreign private issuer. We also expect that if we were required to comply with the rules and regulations applicable to U.S. domestic issuers, it would make it more difficult and expensive for us to obtain director and officer liability insurance, and we may be required to accept reduced coverage or incur substantially higher costs to obtain coverage. These rules and regulations could also make it more difficult for us to attract and retain qualified members of our Board of Directors. If we were to be classified as a passive foreign investment company for U.S. federal income tax purposes, this could result in adverse U.S. tax consequences to certain U.S. holders. If the Company is classified as a passive foreign investment company (PFIC) for any taxable year, U.S. investors may be subject to adverse U.S. federal income tax consequences described below under “Item 10.E Taxation — Certain Material U.S. Federal Income Tax Considerations for U.S. Holders” The Company will be classified as a PFIC for U.S. federal income tax purposes for any taxable year in which, taking into account a pro rata portion of the income and assets of 25% or more owned subsidiaries, either (i) at least 75% of its gross income consists of “passive income” or (ii) at least 50% of the average quarterly value of its assets is attributable to assets that produce, or are held for the production of, passive income. Based on our historic and anticipated operations, the composition of our income and the projected composition and estimated fair market values of our assets, we do not believe that we were a PFIC for our most recent taxable year and do not expect to be classified as a PFIC for the current taxable year or for the foreseeable future. However, our status as a PFIC is a factual determination made on an annual basis, and we cannot provide any assurances regarding our PFIC status for the current or future taxable years.

A.HISTORY AND DEVELOPMENT OF THE COMPANY Our legal and commercial name is argenx SE. We were incorporated under the laws of the Netherlands on April 25, 2008, as a private company with limited liability (besloten vennootschap met beperkte aansprakelijkheid). From incorporation until August 28, 2009, our research and development activities were initially performed in the Netherlands, then Belgium, by argenx N.V. and its legal predecessors. Since August 28, 2009, all our research and development activities have been performed by our wholly-owned subsidiary, argenx BV, under a license provided by argenx N.V. Throughout this time, argenx BV assigned all resulting intellectual property to argenx N.V. On May 28, 2014, we converted to a Dutch public company with limited liability (naamloze vennootschap). On April 26, 2017, we converted to a Dutch European public company with limited liability (Societas Europaea or SE). On May 5, 2017, we transferred the legal ownership of all intellectual property rights of argenx SE to argenx BV, effective retroactively as of January 1, 2017. As a result, since January 1, 2017, (i) argenx BV holds all legal and economic ownership of our intellectual property rights, and (ii) the research and development agreement between argenx SE and argenx BV has been terminated. Our official seat is in Amsterdam, the Netherlands, and our registered office is at Laarderhoogtweg 25, 1101 EB Amsterdam, the Netherlands. We are registered with the trade register of the Dutch Chamber of Commerce under number 24435214. Our European legal entity identifier number (LEI) is 7245009C5FZE6G9ODQ71. Our telephone number is +31 (0) 10 70 38 441. Our website address is www.argenx.com. This website is not incorporated by reference in this Annual Report. The SEC maintains an Internet site that contains reports, proxy and information statements, and other information regarding issuers that file electronically with the SEC at www.sec.gov. The registered agent for service of process in the U.S. is CT Corporation System, with an address at 111 8th Avenue, New York, NY 10011. For information on our capital expenditure for the years ended December 31, 2025, 2024 and 2023, please see “Note 4 — Property, Plant and Equipment” and “Note 5 — Intangible Assets” in our consolidated financial statements which are included at the end of this Annual Report on Form 20-F for the period ended December 31, 2025. We anticipate our capital expenditure in 2026 to be financed from the cash flows from operating activities and cash reserves. For more information on our capital expenditures and requirements, see “Item 5.B. — Liquidity and Capital Resources — Cash Flows — Operating and Capital Expenditure Requirements” in our Annual Report for the period ended December 31, 2025. No takeover bid has been instigated by third parties in respect of our equity during the current or previous fiscal years. 29 Table of Contents B.BUSINESS OVERVIEW Our legal and commercial name is argenx SE. We were incorporated under the laws of the Netherlands on April 25, 2008, as a private company with limited liability (besloten vennootschap met beperkte aansprakelijkheid). From incorporation until August 28, 2009, our research and development activities were initially performed in the Netherlands, then Belgium, by argenx N.V. and its legal predecessors. Since August 28, 2009, all our research and development activities have been performed by our wholly-owned subsidiary, argenx BV, under a license provided by argenx N.V. Throughout this time, argenx BV assigned all resulting intellectual property to argenx N.V. On May 28, 2014, we converted to a Dutch public company with limited liability (naamloze vennootschap). On April 26, 2017, we converted to a Dutch European public company with limited liability (Societas Europaea or SE). On May 5, 2017, we transferred the legal ownership of all intellectual property rights of argenx SE to argenx BV, effective retroactively as of January 1, 2017. As a result, since January 1, 2017, (i) argenx BV holds all legal and economic ownership of our intellectual property rights, and (ii) the research and development agreement between argenx SE and argenx BV has been terminated. For additional information regarding our Company’s principal markets and revenue breakdown, see “Item 5.A. — Operating Results” in our Annual Report for the period ended December 31, 2025. 2025 In Brief Operational Highlights 2025 was a year of strong execution as we advanced our long‑term commitment to patients under Vision 2030: aiming to treat 50,000 patients globally, secure 10 labeled indications across all approved medicines, and advance five pipeline candidates into Phase 3 development by 2030. We made significant progress executing against this goal throughout the year, by expanding our global reach with VYVGART in two blockbuster indications, advancing 10 ongoing registrational clinical trials, and completed our goal to bring forward four Phase 1 molecules by the end of the decade. Throughout 2025, VYVGART continued to deliver meaningful impact for patients globally, reaching more than 19,000 patients across three indications (gMG, CIDP, and ITP) and three product presentations. We successfully launched our PFS, which expanded access to new patient segments and enabled more convenient treatment options. In gMG, we strengthened our position as the #1 prescribed and fastest‑growing biologic, supported by increasingly earlier use in the treatment paradigm and continued expansion into broader patient populations. Positive topline data from the Seronegative gMG clinical trial strengthened our ambition to be the treatment of choice and to pursue the broadest MG label to date. In CIDP, real‑world outcomes continued to validate the ADHERE results, with physicians reporting sustained functional improvement and patients experiencing greater independence and quality of life. This strong commercial execution resulted in a milestone for the Company, with VYVGART surpassing $1 billion in product net sales in a single quarter for the first time in the third quarter of 2025. Across the pipeline, we made meaningful progress on a broad set of programs. We advanced efgartigimod through additional Phase 3 clinical trials that are expected to read out in 2026: Myositis and ITP, each supported by compelling biology and robust clinical or proof‑of‑concept data. Together, we believe these programs strengthen efgartigimod’s position as a foundational FcRn‑based therapy with potential across multiple high‑need autoimmune diseases. Our second asset, empasiprubart, advanced notably with three Phase 3 clinical trials underway in MMN and CIDP. As a first‑in‑class antibody targeting complement C2, we further expanded our understanding of C2 biology and its potential to set a new bar for treatment outcomes in immune‑mediated neuromuscular diseases. Momentum also continued with adimanebart (ARGX‑119), which entered Phase 3 development in CMS and progressed in a proof-of-concept clinical trial in spinal muscular atrophy (SMA). Across our early‑stage portfolio, we advanced key next‑generation programs, which include ARGX-213 and ARGX-124. We have a highly productive IIP, our engine for sourcing novel biology and accelerating differentiated medicines, with over 25 active programs. Together, these achievements and the progress across our pipeline position us well for the year ahead as we prepare for multiple registrational readouts and continued expansion of our global patient impact. Corporate Achievements •Subject to shareholder approval, Karen Massey, current COO, will transition to CEO and Executive Director and Tim Van Hauwermeiren, current CEO, will transition to Non-Executive Chairperson of the Board of Directors. •In 2025, Sandrine Piret-Gérard was appointed Chief Commercialization Officer. Sandrine joins from Gilead, where she lead the U.S. commercial organization. 30 Table of Contents •Anthony Rosenberg, who has served as a non-executive director since April 2017, was reappointed as a non- executive director and vice-chairperson of the Board of Directors for a term of 2 years. •Expansion to 1,863 full-time employees (as of December 31, 2025) to support further growth of our business, including fully staffed commercial teams in the U.S., Europe, Japan and Canada. 2025 Financial Highlights •Product net sales of $4.2 billion •Research & development of $1.4 billion •Financial Strength to Invest in Sustainable innovation. 2026 Outlook 2026 marks a defining year on the path to Vision 2030 with three strategic priorities: •Impact more patients globally with VYVGART, driving broader adoption across current patient populations and unlocking new opportunities with potential label expansions •Shape the long-term future of FcRn medicines, advancing future FcRn molecules, innovative delivery modalities and combination approaches designed to transform patient outcomes •Deliver next wave of immunology innovation, accelerating empasiprubart and diversified pipeline of first-in-class molecules to drive sustainable value creation 31 Table of Contents The table above is subject to risks and uncertainties that may materially impact the achievement of our 2026 outlook. For more information, please refer to “Item 3.D. — Risk Factors” of this Annual Report for a discussion of such risks and uncertainties. Our Medicines VYVGART and VYVGART HYTRULO is a first-and-only immunoglobulin G (IgG) Fc-antibody fragment that targets the FcRn. It is approved for the treatment in three indications, including gMG and CIDP globally and ITP in Japan (as VYVDURA). Our Pipeline •efgartigimod is an IgG1 antibody Fc fragment that has been engineered for increased affinity to FcRn compared to endogenous IgG. Efgartigimod selectively reduces IgG by blocking FcRn-mediated IgG recycling without impacting antibody production or affecting other parts of the immune system. It is approved in three indications, including gMG, CIDP and ITP, and is being evaluated in more than ten additional serious autoimmune indications. •empasiprubart (C2 inhibitor) is a novel complement inhibitor targeting C2, blocking the function of both the classical and lectin pathways while leaving the alternative pathway intact. We believe empasiprubart has the potential to be a pipeline-in-a-product candidate and is being evaluated in two indications currently in Phase 3 clinical trials. •adimanebart (MusK agonist): adimanebart is an agonist SIMPLE ANTIBODY™ to the MuSK receptor with potential in multiple neuromuscular indications. It is currently in clinical trials for CMS (Phase 3 clinical trial) and SMA (Phase 2). •Earlier Stage Programs: ◦Two future FcRn molecules are progressing: ARGX-213, an FcRn-targeted antibody engineered for half-life extension and sustained IgG reduction, and ARGX-124, a first-in-class FcRn pipeline candidate. ◦ARGX-109 (targeting IL-6) and ARGX-121 (a first-in-class molecule targeting immunoglobulin A (IgA)) are also progressing. ◦Entered into a research collaboration with Tensegrity Pharma, including an option for future acquisition, to advance Tensegrity’s lead program TSP-101 in autoimmune disease and other indications. ◦Three new molecules expected to enter Phase 1 clinical trials in 2026, including ARGX-118, a first-in-class molecule targeting Galectin-10, ARGX-125, a first-in-class bispecific antibody, and TSP-101, targeting Fn14. •In addition to our wholly-owned pipeline, we have candidates that emerged from our IIP that we out-licensed to a partner for further development and for which we have milestone, royalty or profit-share agreements. These candidates include, amongst others: cusatuzumab (anti-CD70 antibody – OncoVerity), ARGX-112 (LP-0145 – anti- IL-22R antibody – LEO Pharma), ARGX-114 (AGMB-101 – agonistic anti-MET antibody – Agomab) and ARGX-115 (ABBV-151 – anti-GARP antibody – AbbVie). Immunology Innovation Program (IIP) Our IIP is the engine behind our robust and expansive pipeline. By fostering deep, ongoing collaboration between leading academic researchers and our in-house antibody engineers, we aim to translate breakthrough science into first-in- class therapies across multiple indications. This co-creation model has enabled every candidate in our wholly owned and partnered pipelines to emerge from IIP collaborations, underscoring our ability to identify and advance novel targets with speed and precision. Our approach is designed for scale and sustainability: we run parallel development programs, optimize trial design for efficiency, and maintain a relentless focus on unmet patient needs. This strategy has delivered measurable results – accelerating our path to profitability, driving strong commercial growth, and positioning argenx as a leader in immunology innovation. By integrating the aspirations of patients and the insights of healthcare professionals into every stage of discovery and development, we are not only building a differentiated pipeline but also setting new standards for impact and value creation in the sector.We bring to the collaboration our unique suite of antibody discovery and antibody engineering technologies and experience in clinical development to complement our partners’ expertise in disease and target biology. Our suite of technologies includes amongst others our SIMPLE ANTIBODY™ platform technology and NHANCE™, ABDEG™, POTELLIGENT®, and DHS mutations that focus on engineering the Fc region of antibodies in order to augment their intrinsic therapeutic properties. 32 Table of Contents Our Suite of Technologies •SIMPLE ANTIBODY™ platform technology: Our proprietary SIMPLE ANTIBODY™ platform technology, based on the powerful llama immune system, allows us to exploit novel and complex disease biology targets. The platform sources antibody variable regions (V-regions) from the immune system of outbred llamas, each of which has a different genetic background. The llama produces highly diverse panels of antibodies with a high human homology, or similarity, in their V-regions when immunized with targets of human disease. Our SIMPLE ANTIBODY™ platform technology allows us to access and explore a broad target universe while potentially minimizing the long timelines associated with generating antibody candidates using traditional methods. •NHANCE™, ABDEG™, POTELLIGENT®, and DHS mutations focus on engineering the Fc region of antibodies in order to augment their intrinsic therapeutic properties. In addition, we obtained a non-exclusive research license and option from Chugai Pharmaceutical Co., Ltd. for the SMART-Ig® (“Recycling Antibody” and part of “Sweeping Antibody”) and ACT-Ig® (Antibody half-life extending) technologies. These technologies are designed to enable us to expand the therapeutic index of our product candidates, which is the ratio between toxic and therapeutic dose, by potentially modifying their half-life, tissue penetration, rate of disease target clearance and potency. Our Products and Product Candidates The following table summarizes key information on our portfolio of lead products and product candidates as of the date of this Annual Report. Program Indication Preclinical Phase 1 Proof of Concept Registrational Commercial VYVGART gMG ITP (Japan) VYVGART HYTRULO gMG CIDP efgartigimod Seronegative gMG Ocular MG Primary ITP Graves’ Disease Myositis SjD Systemic Sclerosis AMR empasiprubart MMN DGF CIDP adimanebart CMS SMA ARGX-213 Undisclosed ARGX-121 IgA Nephropathy ARGX-124 Undisclosed ARGX-109 Undisclosed TSP-101 Undisclosed ARGX-118 Undisclosed ARGX-125 Undisclosed NEUROLOGY NEPHROLOGY AND HEMATOLOGY ENDOCRINOLOGY RHEUMATOLOGY UNDISCLOSED 33 Table of Contents Our Programs VYVGART \Approvals and Regulatory Plan VYVGART is approved in more than 30 countries with three active indications (gMG, CIDP and ITP) and three presentations (IV, SC, PFS). More approvals and launches of VYVGART in multiple jurisdictions and countries are planned following pricing and reimbursement negotiations. The following table summarizes the status of regulatory approvals for VYVGART as of February 2026: Product Indication Geography Regulatory Status VYVGART IV VYVGART gMG US Approved VYVGART gMG Europe Approved VYVGART gMG Canada Approved VYVGART gMG Israel Approved VYVGART gMG Japan Approved VYVGART gMG The UK Approved VYVGART gMG China Approved VYVGART gMG Australia Approved VYVGART gMG Kuwait Approved VYVGART gMG Saudi Arabia Approved VYVGART gMG Korea (the Republic of) Approved VYVGART gMG United Arab Emirates Approved VYVGART gMG Switzerland Approved Pending gMG Brazil Submitted VYVGART gMG Singapore Approved VYVGART ITP Japan Approved VYVGART SC VYVGART HYTRULO gMG US Approved VYVGART HYTRULO CIDP US Approved VYVGART gMG Australia Approved VYVGART CIDP Australia Submitted VYVGART gMG Europe Approved VYVGART CIDP Europe Approved VYVGART gMG Switzerland Approved VYVGART CIDP Switzerland Submitted VYVGART gMG The UK Approved VYVGART CIDP The UK Approved VYVGART SC gMG Israel Approved VYVGART HYTRULO gMG China Approved VYVGART HYTRULO CIDP China Approved VYVDURA gMG Japan Approved VYVDURA CIDP Japan Approved PFS VYVDURA gMG Japan Approved VYVDURA CIDP Japan Approved VYVGART HYTRULO gMG U.S. Approved VYVGART HYTRULO CIDP U.S. Approved VYVGART gMG Europe Approved VYVGART CIDP Europe Approved VYVGART SC gMG Canada Approved VYVGART SC CIDP Canada Approved VYVGART gMG The UK Approved VYVGART CIDP The UK Approved VYVGART gMG Australia Approved VYVGART CIDP Australia Submitted VYVGART Switzerland Submitted VYVGART gMG Israel Submitted VYVGART CIDP Israel Submitted 34 Table of Contents Commercialization We have established our own sales force in the U.S., Japan, Europe and Canada for VYVGART for the treatment of gMG and CIDP (where approved). We plan to expand our own sales and marketing capabilities and promote our products and product candidates in other regions if we decide there is a business case to do so after regulatory approval has been obtained. Development and commercialization may also be done through collaborations with third parties. In January 2021, we entered into an exclusive out-license agreement with Zai Lab (Zai Lab Agreement), a commercial-stage biopharmaceutical company, for the development and commercialization of efgartigimod in Greater China, (which includes Mainland China, Hong Kong, Taiwan and Macau, Greater China). Zai Lab announced approval of VYVGART in Mainland China in June 2023 for the treatment of adult gMG patients and in 2024 Zai Lab also announced the approval of VYVGART SC for gMG and CIDP. Under the Zai Lab Agreement, we received and continue to be eligible for certain sales-based milestone payments and royalties based on annual product net sales of efgartigimod in Greater China. We intend to continue expanding into new markets and will evaluate the most appropriate commercialization approach for each territory, whether through our own commercial organization or through additional distribution partnerships. In the U.S., argenx advertises certain products via digital and traditional media channels, including the internet and television. For a discussion of total revenues by geographic market, please see “Note 16 — Segment Reporting” in our consolidated financial statements which are included in our Annual Report for the period ended December 31, 2025. Pre-Approval Access Program We are committed to improving the lives of people suffering from rare diseases. We are driven to discover new treatment approaches fueled by the resilience of patients to urgently deliver them. We aim to do this in partnership; we listen to patients, supporters and advocacy communities, and we hear their stories. Their insights guide us as we develop our investigational therapies and motivate us to advance the understanding of rare diseases. We have a Pre-Approval Access program (PAA) for patients with gMG which opened on February 21, 2021 for patients who are unable to participate in an ongoing clinical trial. In 2024, we approved access to this PAA for over 403 gMG patients in 14 countries. The PAA program remains open in countries where VYVGART is not yet launched or reimbursed. efgartigimod (ARGX-113) Development Mechanism of Action As shown in Figure 1, efgartigimod is a human IgG1 Fc fragment equipped with our ABDEG™ mutations that is designed to target the FcRn and reduce IgG. FcRn is foundational to the immune system and functions to recycle IgG, extending its serum half-life over other IgGs that are not recycled by FcRn. IgGs that bind to FcRn are rescued from lysosomal degradation. By binding to FcRn, efgartigimod can reduce IgG recycling and increase IgG degradation. 35 Table of Contents Figure 1: efgartigimod’s mechanism of action blocks the recycling of IgG antibodies and removes them from circulation. FcRn, neonatal Fc receptor; Ig, immunoglobulin; LDL, low-density lipoprotein. 1) Ulrichts P, et al. J Clin Invest. 2018;128:4372–86 6) Roopenian DC, Akilesh S. Nat Rev Immunol. 2007;7:715–25. 7) Ward ES, Ober RJ. Trends Pharmacol Sci. 2018;39:892–904. Formulations Overview We are developing two formulations of efgartigimod to address the needs of patients, physicians, and payers across indications and geographies, including efgartigimod IV (VYVGART) and efgartigimod SC (VYVGART SC). efgartigimod Indications Clinical trial overview Clinical Trial Stage Indica­tion Patients Primary Endpoint Status ADAPT Registrational gMG The proportion of responders based on the Myasthenia Gravis Activities of Daily Living (MG-ADL) score Marketed ADAPT-SC Registrational gMG The proportion of responders based on the Myasthenia Gravis Activities of Daily Living (MG-ADL) score Marketed ADAPT-SERON Registrational Seronegative gMG 119 MG-ADL total score change from baseline to day 29 (w4) Positive clinical trial results reported in 2025 with expected PDUFA date of May 10, 2026 ADAPT-OCULUS Registrational Ocular MG 141 Change in MGII PRO ocular score from baseline to day 29 (w4) Positive clinical trial results reported in February 2026 ADHERE Registrational CIDP 322 The hazard ratio for the time to first adjusted INCAT deterioration Marketed ADVANCE-IV Registrational ITP The proportion of patients that achieved sustained platelet response Marketed 36 Table of Contents Clinical Trial Stage Indica­tion Patients Primary Endpoint Status ADVANCE-NXT Registrational ITP 63 Extent of disease control (cumulative number of weeks over the planned 24-week treatment period with platelet counts of ≥ 50×109/L Ongoing clinical trial results expected in 4Q 2026 ALKIVIA Registrational Myositis Target 240 The total improvement score (TIS) at the end of treatment period Ongoing clinical trial results expected in 3Q 2026 UNITY Registrational SjD Target 580 The change from baseline on the ClinESSDAI score (w48) Ongoing clinical trial results expected in 2H 2027 In partnership with Zai Lab PoC LN Target 60 The change in urine protein creatinine ratio from baseline to end of the treatment period Clinical trial discontinued in 2025 uplighTED Registrational TED Target 108/trial Percentage of participants who were proptosis responders at week 24 Clinical trial discontinued in 2025 shAMRock PoC AMR Target 30 Safety and tolerability. Efficacy measures such as estimated glomerular filtration rate, histology and urine protein creatinine ratio are captured in the secondary endpoints Ongoing clinical trial ADAPT-JUNIOR IV Phase 2/3 gMG Target over 12 To confirm an age-adjusted optimum dose of efgartigimod IV and provide (model-predicted) evidence for a treatment response Ongoing clinical trial ADAPT-JUNIOR SC Phase 2/3 gMG Target over 12 To confirm an appropriate dose of efgartigimod PH20 SC in pediatric participants with gMG Ongoing clinical trial Other clinical trials PoC AIE To be confirmed Ongoing clinical trial PoC AIM To be confirmed To be confirmed Ongoing clinical trial gMG Overview gMG is a rare, chronic autoimmune disease in which pathogenic IgG autoantibodies disrupt neuromuscular signaling, leading to fluctuating and sometimes life‑threatening muscle weakness. Autoantibodies block or remove acetylcholine receptors and activate complement, damaging the neuromuscular junction. MG often begins with ocular symptoms such as ptosis and diplopia, and approximately 85% of patients progress to generalized MG (gMG), which can impair bulbar, limb, and respiratory function. Respiratory crises occur in 15–20% of patients. MG prevalence in the U.S. is estimated at approximately 20 per 100,000, and roughly 85% of gMG patients have detectable AChR antibodies. efgartigimod has demonstrated consistent and robust clinical benefit across MG populations. Pivotal ADAPT data formed the basis for global approvals of VYVGART IV, and positive ADAPT‑SC results supported approval of the subcutaneous formulation. In 2025, we reported positive topline results from ADAPT‑SERON, our Phase 3 clinical trial in anti‑AChR antibody‑negative gMG, demonstrating a clear treatment effect and reinforcing the broad applicability of FcRn across MG subtypes. These data support our supplemental regulatory submission to expand VYVGART into the seronegative population, which was accpeted for priority review with an expected PDUFA target action date of May 10, 2026. We also reported positive data from our ADAPT OCULUS clinical trial, which met its primary endpoint, showing that patients living with oMG and treated with VYVGART demonstrated statistically significant improvement from baseline in Myasthenia Impairment Index (MGII) Patient Reported Outcome (PRO) ocular scores at Week 4 compared to placebo. The results support our supplemental regulatory submissions to expand VYVGART into the ocular MG population. We also have ongoing clinical trials in pediatric gMG patients (ADAPT-JUNIOR) with efgartigimod IV and efgartigimod SC. 37 Table of Contents CIDP Overview CIDP is a chronic autoimmune disorder of peripheral nerves and nerve roots caused by an autoimmune-mediated destruction of the myelin sheath, or myelin producing cells, insulating the axon of the nerves and enabling speed of signal transduction. The cause of CIDP is unknown, but abnormalities in both cellular and humoral immunity have been shown. CIDP is a chronic and progressive disease: onset and progression occur over at least eight weeks in contrast with the more acute Guillain-Barré-syndrome. Demyelination and axonal damage in CIDP lead to loss of sensory and/or motor neuron function, which can lead to weakness, sensory loss, imbalance and/or pain. The U.S. prevalence is estimated at approximately 42,000 patients, of whom roughly 24,000 receive treatment. Most patients rely on IVIg as first‑line therapy, while glucocorticoids, plasma exchange, and other immunosuppressants are used less frequently given safety, tolerability, and access limitations. In July 2023, the pivotal ADHERE clinical trial demonstrated that VYVGART SC significantly reduced the risk of relapse compared to placebo and provided evidence that pathogenic IgG autoantibodies play an important role in CIDP biology. Sixty‑seven percent of patients entering the open‑label Stage A improved clinically, and efgartigimod SC was well tolerated with a safety profile consistent with prior clinical trials. Nearly all eligible patients (99%) continued into the ADHERE‑Plus OLE. Based on these data, VYVGART SC received regulatory approvals in the U.S. in June 2024, in China in November 2024, and in Japan in December 2024, with regulatory review ongoing in additional jurisdictions, including the EU. Primary ITP Overview Primary ITP is an acquired autoimmune bleeding disorder, characterized by a low platelet count (<100×109/L) in the absence of other causes associated with thrombocytopenia. In most patients, IgG autoantibodies directed against platelet receptors can be detected. They accelerate platelet clearance and destruction, inhibit platelet production, and impair platelet function, resulting in increased risk of bleeding and impaired quality of life. Primary ITP is differentiated from secondary ITP, which is associated with other illnesses, such as infections or autoimmune diseases, or which occurs after transfusion or taking other drugs, such as cancer drugs. Platelet deficiency, or thrombocytopenia, can cause bleeding in tissues, bruising and slow blood clotting after injury. Patients may suffer from depression and fatigue as well as side effects of existing therapies, impairing their quality of life. Current therapeutic approaches include non-specific immunosuppression (e.g., steroids and rituximab), inhibition of platelet clearance (e.g., splenectomy, IVIg, anti-D globulin, and spleen tyrosine kinase inhibitor fostamatinib13) or stimulation of platelet production (e.g., thrombopoietin receptor agonist TPO-RA). Splenectomy remains the only treatment that provides sustained remission off therapy for one year or longer for a high proportion of patients. ITP affects approximately 72,000 patients in the U.S. In 2022, the Phase 3 ADVANCE (IV) clinical trial met its primary endpoint, demonstrating that a higher proportion of chronic ITP patients receiving efgartigimod achieved a sustained platelet count response compared to placebo. These results supported approval of efgartigimod for ITP in Japan. In 2023, the accompanying subcutaneous clinical trial, ADVANCE‑SC, did not meet its primary endpoint. To fulfill the requirement for two well-controlled trials needed for global registration, argenx is now conducting ADVANCE‑NEXT, a Phase 3, randomized, double‑blinded, placebo‑controlled trial evaluating efgartigimod IV in adults with primary ITP. ADVANCE-NEXT remains ongoing, with topline Phase 3 results expected in the fourth quarter of 2026. AIM Overview AIM are a rare and heterogeneous group of autoimmune diseases that can affect muscle alone or multiple organ systems, including the skin, joints, lungs, gastrointestinal tract, and heart. These conditions are severe, disabling, and materially impact quality of life. Advances in understanding disease biology and the discovery of characteristic autoantibodies have led to clearer differentiation of AIM into clinically meaningful subtypes, including immune‑mediated necrotizing myopathy (IMNM), antisynthetase syndrome (ASyS), and dermatomyositis (DM). Each subtype presents with distinct autoantibody profiles and manifestations, though proximal muscle weakness remains a defining feature across AIM. Today, there are no FDA‑approved therapies for IMNM or ASyS, and treatment is largely dependent on steroids or broad immunosuppressants; IVIg was approved for DM in 2021. argenx is advancing the registrational ALKIVIA clinical trial of efgartigimod SC for the treatment of AIM. ALKIVIA is a seamless Phase 2/3 clinical trial enrolling approximately 240 patients across IMNM, ASyS, and DM, with Total Improvement Score (TIS) as the primary endpoint and a broad set of functional and quality‑of‑life secondary measures. 38 Table of Contents In November 2024, following achievement of statistical significance on the primary endpoint in the Phase 2 portion and consistent improvement across all six core components of the TIS, argenx announced a ‘GO’ decision to proceed with the Phase 3 portion in all three AIM subtypes. Safety and tolerability were consistent with the known profile of efgartigimod. ALKIVIA remains ongoing, with topline Phase 3 results expected in the third quarter of 2026. SjD Overview SjD is a chronic, progressive autoimmune disease, characterized by lymphocytic infiltration and progressive destruction of exocrine glands. B-cells play a pivotal role in the development of the disease and this results amongst others in production of IgG autoantibodies, especially those which target SSA/Ro, SSB/La ribonuclear complexes. In addition to symptoms of dry eyes, dry mouth, chronic pain and fatigue, a substantial subset of patients suffer from extraglandular systemic disease. There are no FDA-approved treatments currently registered for the treatment of SjD. argenx is advancing the registrational UNITY clinical trial of efgartigimod SC for the treatment of SjD. UNITY is a Phase 3, randomized, placebo‑controlled, double‑blind clinical trial assessing the safety and efficacy of efgartigimod SC in 480 patients with at least moderate systemic disease (ClinESSDAI ≥6) who are on stable background therapy and positive for anti‑SSA/Ro. After the 48‑week treatment period, eligible participants may roll over into an OLE. The primary endpoint is change from baseline in clinESSDAI, with key secondary endpoints focused on patient‑reported outcomes, ESSDAI, and STAR. UNITY remains ongoing, with topline Phase 3 results expected in the second half of 2027. empasiprubart (ARGX-117) Development Mechanism of Action empasiprubart is a differentiated therapeutic mAb targeting C2 equipped with our proprietary NHANCE™ mutations. By addressing a novel target at the intersection of the complement and lectin pathways of the complement cascade, we believe empasiprubart represents a broad pipeline opportunity across several severe autoimmune indications. Activation of the classical and lectin pathway of complement may contribute to tissue damage and organ dysfunction in a number of autoimmune inflammatory diseases and ischemia-reperfusion conditions. Targeting C2 also leaves the alternative pathway of the complement system intact, which is an important component of the innate defense system. empasiprubart exhibits both pH- and calcium dependent binding. These unique characteristics enable empasiprubart to capture free C2 in circulation and release it in the endosome to be sorted for degradation in the lysosome. empasiprubart is equipped with NHANCE™ mutations increasing its affinity for FcRn and allowing it to recycle back into circulation to capture more C2. In addition to an IV formulation, we have exclusive access to Halozyme’s ENHANZE® SC drug delivery technology for the C2 target. 39 Table of Contents Figure 2: empasiprubart mechanism of action. C2, complement component 2; FcRn, neonatal Fc receptor; IgG, immunoglobulin G. 1) Van de Walle I, et al. J Allergy Clin Immunol. 2021;147:1420–9. 2) Vaccaro C, et al. Proc Natl Acad Sci. 2006;103:18709–14. 3) Brinkhaus M, et al. Nat Commun. 2022;13:6073. empasiprubart Indications MMN Overview MMN is a debilitating neuromuscular autoimmune disorder that is characterized by slowly progressive muscle weakness due to motor neuron degeneration. It mainly affects hands and forearms, mainly in males, and the median age of diagnosis is around 40 years. Diagnosis takes about a year and a half and is often misdiagnosed as ALS. There are estimated to be around 12,000 patients across key markets. Specific pathophysiologic characteristics of MMN include the presence of IgM autoantibodies against the ganglioside GM1 and conduction block, i.e., impaired propagation of action potentials along the axon. GM1 is widely expressed in the nervous system by neurons, particularly around the nodes of Ranvier, and Schwann cells. IVIg is the only approved treatment for MMN and needs to be dosed frequently to address the disease’s progressive nature. Phase 2 POC ARDA Clinical Trial The Phase 2 POC ARDA clinical trial was a randomized, double‑blinded, placebo‑controlled multicenter clinical trial evaluating the safety and tolerability, efficacy, PK, PD, and immunogenicity of two dose regimens of empasiprubart in adults with MMN. Safety and tolerability were the primary endpoint and additional endpoints included time to IVIg retreatment, biomarker analyses of C2 levels, and changes in key functional scores (modified medical research council‑10 sum score, grip strength, MMN‑RODS) as well as several patient‑reported quality‑of‑life measures (fatigue severity score (FSS), chronic acquired polyneuropathy patient‑reported index (CAP‑PRI), and patient global impression change scale). In 2024, argenx announced positive data from the first cohort (n=16), which were confirmed with the second cohort (n=16) in July 2024, establishing POC in MMN, with empasiprubart demonstrating a 91% reduction in the need for IVIg rescue compared to placebo [HR (95% CI)=0.09 (0.02; 0.44)] in cohort 1 and an 84% reduction in IVIg rescue compared to placebo [HR (95% CI)=0.16 (0.02; 1.54)] in cohort 2. 40 Table of Contents Based on these results argenx initiated the EMPASSION Phase 3 clinical trial evaluating empasiprubart in MMN head to head with IVIg at the end of 2024. Phase 3 EMPASSION Clinical Trial Design A Phase 3, randomized, double-blinded, double-dummy clinical trial evaluating the efficacy and safety of empasiprubart versus intravenous immunoglobulin in adults with multifocal motor neuropathy. The clinical trial comprises a screening period of up to 15 weeks, including a minimum of 2 IVIg cycles; a 24-week (6-month), randomized, double-blinded, double-dummy treatment period (part A) evaluating the efficacy and safety of empasiprubart vs IVIg continuation; a 24-month OLE period (part B); and a 15-month safety follow-up period starting after the last dose of IMP. The primary objective is to demonstrate the efficacy of empasiprubart compared to IVIg in improving functional ability. This will be measured by change from baseline in the 25-item MMN-RODS centile score at week 24. Additional key secondary endpoints include changes in measurements on key functional scores (modified medical research council -14 sum score, grip strength) as well as patient-reported quality of life outcome measures (polyneuropathy patient-reported index, and values of the patient global impression change scale and evaluation of manual dexterity using 9HPT. DGF Delayed graft function (DGF), defined as the need for dialysis in the first week after kidney transplant, affects up to 40% of deceased‑donor recipients and is associated with poorer long‑term outcomes. Decision for Phase 2 VARVARA clinical trial is now expected mid-year 2026 to complete 52-week efficacy analysis CIDP Overview Please refer to “Item 4.B — efgartigimod Indications” (CIDP) for more information on CIDP. Phase 3 EMVIGORATE and EMNERGIZE Clinical Trials argenx is advancing two Phase 3 clinical trials of empasiprubart in CIDP: EMVIGORATE and EMNERGIZE. EMVIGORATE is a head‑to‑head clinical trial comparing empasiprubart to IVIg in adults with CIDP. EMNERGIZE is a randomized, placebo‑controlled clinical trial evaluating the efficacy and safety of empasiprubart. Topline results from both EMVIGORATE and EMNERGIZE are expected in the second half of 2027. adimanebart (ARGX-119) Development adimanebart is a humanized agonist monoclonal antibody that specifically targets and activates MuSK to promote maturation and stabilization of the NMJ, with planned development across severe neuromuscular diseases including CMS, ALS, and SMA. It is the first highly specific agonist mAb targeting human MuSK and was developed using the SIMPLE ANTIBODY™ platform in collaboration with leading experts, with preclinical proof‑of‑concept demonstrated in a DOK7‑CMS model. A Phase 3 clinical trial in CMS is expected to initiate in the third quarter of 2026, following positive results from the Phase 1b clinical trial. A proof-of-concept clinical trial is also ongoing in SMA. Strategy and Objectives Company’s Strategies Our objective is to transform the lives of at least 50,000 patients and their communities before 2030 by providing them with life-changing medicines built on scientific breakthroughs in immunology. To reach this, we aim to deliver on a set of different goals: •Transform the lives of 50,000 patients, by redefining treatment expectations in MG & CIDP and delivering at least eight additional labeled indications and a second self-administered FcRn medicine by 2030. 41 Table of Contents •Be the precision complement inhibitor that sets a new SOC and improves patient experience and outcomes across indications, with 3+ labeled indications and five total indications in development by 2030. •Be the leader in neuromuscular junction (NMJ) therapeutics, redefining patient expectations and reigniting hope in one labeled indication and at least four total indications by 2030. •Expand our pipeline of transformational innovation to enable consistent cadence of value creation for patients; >5 new molecules in late stage by 2030. •Scale in The argenx Way to remain a unique, independent company. •Solidify our place in the biotech ecosystem as the benchmark for entrepreneurial science delivering value for patients. Competitive position We participate in a highly innovative industry characterized by a rapidly growing understanding of disease biology, quickly changing technologies, strong intellectual property barriers to entry, and a multitude of companies involved in the creation, development and commercialization of novel therapeutics. Many of these companies are highly sophisticated and often strategically collaborate with each other. Competition in the autoimmune field is intense and involves multiple monoclonal antibodies (mAbs), other biologics and small molecules either already marketed or in development by many different companies, including large pharmaceutical companies. We compete with a wide range of biopharmaceutical companies that are developing products for the treatment of gMG, CIDP, ITP and other autoimmune diseases, including products that are in the same class as VYVGART, as well as products that are similar to some of our product candidates. We are aware of several FcRn inhibitors that are in clinical development or marketed. In addition, we may face future competition from biosimilar versions of approved biologics in the autoimmune and immunology fields. The regulatory frameworks in the United States, Europe and other key markets could evolve in ways that may facilitate the entry of biosimilars once reference products lose market exclusivity. While FcRn inhibitors are a relatively new therapeutic class, the broader biologics market has seen an increase in biosimilar development and commercial activity, supported by maturing regulatory pathways, expanding manufacturing capabilities and ongoing payer and health‑system initiatives aimed at reducing the cost of care. Competitive product launches may erode future sales of our products, including our existing products and those currently under development, or result in unanticipated product obsolescence. Such launches continue to occur, and potentially competitive products are in various stages of development. We could also face competition for use of limited international infusion sites, particularly in new markets as competitors launch new products. We cannot predict with accuracy the timing or impact of the introduction of competitive products that treat diseases and conditions like those treated by our products or product candidates. In addition, our competitors compete with us to recruit and retain qualified scientific and management personnel, establish clinical trial sites and patient registration for clinical trials, as well as in acquiring technologies complementary to, or necessary for, the development of our products. Please refer to “Item 3.D. — Risk Factors — Risk Factors Related to Commercialization of argenx's Products and Product Candidates, Including for New Indications — We face significant competition for our drug discovery and development efforts” We compete in this dynamic landscape by aiming to advancing differentiated, first‑in‑class and best‑in‑class therapies grounded in novel biology, enabled by our deep scientific expertise and our technology platforms. Our strategy is to innovate ahead of the field—identifying new pathways, engineering unique mechanisms of action, and continuously expanding our understanding of Fc‑mediated biology and related immunology. We also actively protect and strengthen our intellectual property through a comprehensive global portfolio of patents, trade secrets and proprietary know‑how covering our product candidates, platforms and manufacturing processes. This commitment to scientific innovation and robust IP protection is central to sustaining our competitive position and delivering long‑term value. Manufacturing and Supply At argenx, our manufacturing and supply strategy is built for scale, resilience, and speed, reflecting our commitment to move science forward and deliver for patients worldwide. We utilize third-party contract manufacturers who act in accordance with the FDA’s current good manufacturing practices (cGMPs) for the manufacture of drug substances and drug products. We partner with a global network of contract manufacturers who share our standards for quality and innovation, with the goal that every step, from cell bank development to large-scale drug substance production, meets the highest industry benchmarks. Our global supply chain and distribution strategy is to serve patients in region for that region. We work with Lonza teams based in Slough, UK, Portsmouth, U.S., Singapore and Visp, Switzerland for 42 Table of Contents activities relating to the development of cell banks, development of our manufacturing processes and the manufacturing of drug substance, thereby using validated and scalable systems broadly accepted in our industry. In 2022, we started our collaboration with FUJIFILM Diosynth Biotechnologies Denmark ApS (Fujifilm) based in Hillerød, Denmark, for activities relating to the large-scale manufacturing of efgartigimod drug substance. In 2025, we expanded our partnership with Fujifilm to include new manufacturing site in North Carolina, U.S., strengthening our global supply chain and supporting anticipated growth in efgartigimod and pipeline assets. We use additional contract manufacturers to fill, label, package, store and distribute (investigational) drug products. Intellectual Property Introduction We strive to protect and maintain exclusivity for the proprietary technologies that we believe are important to our patients, business, and shareholders. We continue to pursue and maintain patent protection intended to cover core platform technologies incorporated into, or used to produce, our product candidates and commercial products. We will seek protection for our patient innovations in key global jurisdictions. We continue to focus our exclusivity strategies on all aspects of our assets, including our compositions of matter, methods of use for our approved products, and other inventions that are important to our business (e.g., the patient innovations described in our product labels/product inserts and our core manufacturing technologies). Our intellectual property portfolio continues to grow and keep pace with the innovations arising from our discovery, development, and commercial efforts. We expect the total volume of patent positions under our management to increase each year as our pipeline evolves. We currently oversee more than 500 pending applications and granted patents. More importantly, as we continue to innovate for patients, we will work to protect our patient innovations with new intellectual property filings to enable future reinvestment for patients. In addition to patent protection, we rely on trademarks and trade secrets to protect aspects of our business that are not amenable to, or that we do not consider appropriate for, patent protection, including certain aspects of our llama immunization and antibody affinity maturation approaches. Our commercial success depends in part upon our ability to obtain and maintain exclusivity, including regulatory exclusivities, patent, trade secret, and other proprietary protection for commercially important technologies, inventions and know-how related to our business. We will defend and enforce our intellectual property rights, particularly our patent rights, and preserve the confidentiality of our trade secrets while operating without infringing valid and enforceable intellectual property rights of others. Specifically, we are materially dependent on elements of our regulatory, patent and other proprietary protection, including certain of those related to our core platform technologies, described in “Item 4.B. — Business Overview — Intellectual Property — Platform Technologies” below and our product candidates, as described in “Item 4.B. — Business Overview — Intellectual Property — Our internal Programs” below and “Item 4.B. — Business Overview — Intellectual Property — Our Partnered Programs” below. The patent positions for biotechnology companies like us are generally uncertain and can involve complex legal, scientific, and factual issues. In addition, the coverage recited in the claims in a patent application can be significantly reduced before a patent is issued, and claim scope can be reinterpreted and even challenged after issuance. As a result, we cannot guarantee that any of our platform technologies and product candidates, or products will be protectable or remain protected by valid and enforceable patents. We cannot accurately predict whether pending patent applications will issue as patents in any particular jurisdiction or whether the claims of any issued patents will provide sufficient protection from infringing competitors. Any patents we hold may be challenged, circumvented, limited or invalidated by third parties. The term of individual patents depends on the patent laws in the countries in which they are obtained. In most countries, the patent term is 20 years from the earliest date of filing a non-provisional patent application. In the U.S., the term of a patent covering an FDA-approved drug may be eligible for a limited patent term extension under the Drug Price Competition and Patent Term Restoration Act of 1984 (Hatch-Waxman Act) as compensation for the loss of patent term during the FDA regulatory review process as described in “Item 4.B. — Business Overview — Regulation — Licensure and Regulation of Biologics in the U.S.” below. Similar provisions are available in the EU and in other jurisdictions to extend the term of a patent that covers an approved drug and/or its use. It is possible that issued U.S. patents covering each of our products/product candidates may be entitled to patent term extensions. If our product candidates receive FDA approval, we intend to apply for patent term extensions, if available, to extend the term of patents that cover the approved product candidates and/or their uses. We also intend to seek patent term extensions in any jurisdictions where available. There is no guarantee that the applicable authorities, including the FDA, will agree with our assessment of whether such extensions should be granted, and if granted, the length of such extensions. 43 Table of Contents Platform Technologies With regard to our platform technologies, we own or control intellectual property rights directed to our SIMPLE ANTIBODY™ discovery platform, the ABDEG™ and NHANCE™ technologies. With regard to our SIMPLE ANTIBODY™ discovery platform, we have a broad patent portfolio providing exclusivity on the SIMPLE ANTIBODY™ platform. We expect to enjoy exclusivity under this patent portfolio until between 2029 and 2033. With regard to the ABDEG™ platform, we co-own the technology with the University of Texas Southwestern Medical Center and enjoy certain exclusive license rights. We have a broad patent portfolio covering the composition of matter and uses of certain FcRn antagonists to achieve certain biological effects. A composition of matter patent expires in 2036 in the U.S., whereas in many other countries the base expiry date is 2034. With regard to the NHANCE™ platform, we exclusively licensed two U.S. patents from the University of Texas Southwestern Medical Center with composition of matter claims directed to an IgG molecule comprising a variant human Fc domain, and method of use claims directed to a method of blocking FcRn function in a subject by providing to the subject such an IgG molecule. The U.S. patents are expected to expire between 2027 to 2028. The patent family also includes a granted European patent. Our Internal Programs efgartigimod efgartigimod incorporates the ABDEG™ platform technology, for which we co-own the technology with the University of Texas Southwestern Medical Center and enjoy certain exclusive license rights. We have a broad patent portfolio with multiple patent families covering the composition of matter and uses of certain FcRn antagonists to achieve disease- modifying effects. A composition of matter and other relevant patents arising from the same patent family in the U.S. expire in 2036 and 2037 in Europe whereas in many other countries the base expiry date is 2034. We anticipate several more patient innovations to evolve during development and commercialization for which we will seek additional patent protection with later expiration dates. Our ARGX-109 Product Candidate With regard to our wholly-owned ARGX-109 product candidate, we have one patent family with composition of matter claims directed to ARGX-109. The patent family has a base expiry date in 2033. We anticipate several more patient innovations to evolve during development for which we will seek additional patent protection. Furthermore, ARGX-109 incorporates or employs the SIMPLE ANTIBODY™ platform technology and the NHANCE™ platform technology. empasiprubart Product Candidate With regard to the empasiprubart product candidate, we own or have rights to multiple patent families (with several granted patents and pending patent applications in multiple jurisdictions in North America, South America, the EU and Asia, directed to composition of matter claims and method of treatment claims. The patent families have base expiry dates in 2034, 2039 and 2040. We anticipate several more patient innovations to evolve during development for which we will seek additional patent protection. empasiprubart product candidate incorporates or employs the NHANCE™ platform technology. adimanebart Product Candidate With regard to the adimanebart product candidate, we in-licensed patent families from/with New York University Langone Health, a U.S. medical center based in New York, and additional patent families from/with the Leiden University Medical Centre, with a U.S. granted patent and several pending applications in multiple jurisdictions . We anticipate several more patient innovations to evolve during development for which we will seek additional patent protection. Our ARGX-118 Product Candidate With regard to the ARGX-118 product candidate, we co-own a patent portfolio with VIB, an inflammation research center in Ghent, Brussels, and Ghent University, with one U.S. granted patent and pending patent applications in multiple jurisdictions in North America, South America, the EU and Asia. The patent family has a base expiry date in 2039. 44 Table of Contents Our Partnered Programs Our cusatuzumab (ARGX-110) Product Candidate With regard to the cusatuzumab product candidate, we have a broad patent portfolio that include claims to the composition of matter, uses of the molecule, and other important inventions. The issued U.S. patents expire in 2032 and 2033, without taking a potential patent term extension into account. cusatuzumab incorporates or employs the SIMPLE ANTIBODY™ and POTELLIGENT® platform technologies. Our ARGX-115 (ABBV-151) Product Candidate With regard to the ARGX-115 (ABBV-151) product candidate that we co-own with, and exclusively license from, the Ludwig Institute for Cancer Research and UCL, we have a patent portfolio that includes a U.S. patent with a base expiry date in 2034, without taking a potential patent term extension into account. There is a second family with meaningful patent coverage to the composition of matter and epitope claims that are expected to expire in 2036 and 2038. Furthermore, ARGX-115 (ABBV-151) incorporates or employs the SIMPLE ANTIBODY™ platform technology. Our ARGX-112 (LP-0145) Product Candidate With regard to the ARGX-112 (LP-0145) product candidate, we have one patent family with composition of matter claims directed to an antibody that binds human IL-22R. The patent family has a base expiry date in 2037. Furthermore, ARGX-112 (LP-0145) incorporates the SIMPLE ANTIBODY™ platform technology. Collaborations and licenses At argenx, our approach to collaboration and licensing is rooted in the conviction that progress accelerates when boundaries are challenged and expertise is shared. We follow a disciplined strategy to maximize the value of our pipeline. We retain full development and commercialization rights for programs where we believe our platform and capabilities can deliver the greatest impact, ensuring we capture the full value of our innovation. At the same time, we actively seek out partnerships with organizations that share our drive to redefine what’s possible, leveraging complementary strengths to unlock new opportunities for patients. Our licensing strategy is dynamic and pragmatic: we license out select intellectual property to expand the reach of our science, while we also in-license or acquire technologies and assets that can amplify our pipeline or accelerate development. We have partnered, and plan to continue to partner, to develop products and product candidates that we believe have promising utility in disease areas or have patient populations that may benefit from resources of other biopharmaceutical companies. We believe every agreement is shaped by a clear-eyed focus on execution, mutual benefit, and the potential to create lasting change. We aim to be disciplined in our diligence and financial commitments, but not at the expense of agility or ambition. By building alliances that transcend traditional hierarchies and by staying relentlessly focused on unmet needs, we are not just advancing our own portfolio, we are helping to reshape the landscape of immunology for the long term. We also have several license agreements in place, under which we license patents, patent applications and other intellectual property to third parties. We have also entered into several license agreements under which we license patents, patent applications and other intellectual property from third parties. License agreements can relate to research and development and/or commercialization of the relevant product candidates (and technologies) or products. The licensed intellectual property covers some of our product candidates and some of the antibody engineering technologies that we use. Some of these licenses impose various diligence and financial payment obligations on us. We expect to continue to enter into these types of license agreements in the future. We have entered into multiple collaboration agreements with pharmaceutical partners and license agreements, some of which are described below. Our Strategic Partnership with Zai Lab for efgartigimod Pursuant to the Zai Lab Agreement, Zai Lab obtained the exclusive right to develop and commercialize efgartigimod in Greater China. Zai Lab will also contribute patients to our global Phase 3 clinical trials of efgartigimod. Our Zai Lab strategic collaboration allows us to accelerate development of efgartigimod into new autoimmune indications with Zai Lab taking operational leadership of selected Phase 2 POC Clinical trials. We are eligible to receive a one-time sales based milestone and tiered royalties based on annual net sales of efgartigimod in Greater China thereafter. 45 Table of Contents Our Exclusive License with Halozyme for ENHANZE® In February 2019, we entered into an in-license agreement with Halozyme for the use of certain patents, materials and know-how owned by Halozyme and relating to its ENHANZE®, for application in the field of prevention and treatment of human diseases (the ENHANZE® License Agreement). Pursuant to the ENHANZE® License Agreement, we were granted exclusive rights to apply ENHANZE® to biologic products against pre-specified targets, in order to research, develop and commercialize SC formulations of our therapeutic antibody-based product candidates. Our first therapeutic target for which we received an exclusive license from Halozyme was FcRn, which allows us to apply ENHANZE® to efgartigimod and any other product candidates selective and specific for FcRn. Moreover, the breadth of our exclusive license to FcRn precludes either Halozyme itself or any of its current or future partners from utilizing ENHANZE® in the context of an FcRn-targeted product. Our second therapeutic target for which we received an exclusive license from Halozyme was human C2 associated with the product candidate empasiprubart, which is being developed to treat severe autoimmune diseases. Pursuant to the ENHANZE® License Agreement, we also have the right to nominate future targets for an exclusive ENHANZE® license if the target in question has not already been licensed by Halozyme or is not already being pursued by Halozyme. We have expanded our collaboration with Halozyme for ENHANZE® drug delivery technology to additional targets for a total of six, including FcRn and C2. We may terminate the ENHANZE® License Agreement at any time, either in its entirety or on a target-by-target basis, by sending Halozyme prior written notice. Absent early termination, the ENHANZE® License Agreement will automatically expire upon the expiry of our royalty payment obligations under the agreement. In the event the ENHANZE® License Agreement is terminated for any reason, the license granted to us would terminate but Halozyme would grant our sublicensees a direct license following such termination. In the event the ENHANZE® License Agreement is terminated other than for our breach, we would retain the right to sell licensed products then on hand for a certain period of time post-termination. Our Exclusive License with the University of Texas for NHANCE™ and ABDEG™ In February 2012, we entered into an exclusive in-license with the Board of Regents of the University of Texas System (UT BoR) for the use of certain patent rights relating to the NHANCE™ platform for any use worldwide (the UT Agreement). The UT Agreement was amended on December 23, 2014 to also include certain additional patent rights relating to the ABDEG™ platform. Upon commercialization of any of our products that use the in-licensed patent rights, we will be obligated to pay UT BoR a percentage of net sales as a royalty until the expiration of any patents covering the product. This royalty varies with net sales volume and is subject to an adjustment for royalties we receive from a sublicensee of our rights under the UT Agreement, but in any event does not exceed 1%. In addition, we must make annual license maintenance payments to UT BoR until termination of the UT Agreement and we have assumed certain development and commercial milestone payment and reimbursement obligations. We also have diligence requirements with respect to development and commercialization of products which use the in-licensed patent rights. Pursuant to the UT Agreement, we may grant sublicenses to third parties. If we receive any non-royalty income in connection with such sublicenses, we must pay UT BoR a percentage of such income varying from low-middle single digits to middle-upper single digits depending on the nature of the sublicense. Such fees are waived if a sublicensee agrees to pay the milestone payments as set forth in the UT Agreement. We may unilaterally terminate the UT Agreement for convenience upon prior written notice. Absent early termination, the UT Agreement will automatically expire upon the expiration of all issued patents and filed patent applications within the patent rights covered by the UT Agreement. Our royalty payment obligations expire, on a product-by-product and country-by-country basis, at such time as there are no valid claims covering such product. OncoVerity for cusatuzumab In 2022, we, the University of Colorado Anschutz Medical Campus and the University of Colorado Health (UCHealth) created an asset-centric spin-off, OncoVerity, Inc (OncoVerity), focused on optimizing and advancing the development of cusatuzumab, a novel anti-CD70 antibody, in acute myeloid leukemia (AML). OncoVerity is an entity of co-creation, combining the extensive translational biology insights from Dr. Clayton Smith, M.D. from the University of Colorado with our experience on the CD70/CD27 pathway. In 2023, we granted an exclusive license for cusatuzumab to OncoVerity and provided, together with a joint venture of University of Colorado Health and University License Equity Holdings, Inc. on the University of Colorado Anschutz Medical Campus, and funding for ongoing clinical development of cusatuzumab. 46 Table of Contents In 2024 and 2025, we participated in a further funding round to support the continued, ongoing, clinical development of cusatuzumab by OncoVerity. Our Strategic Partnership with AbbVie for ARGX-115 (ABBV-151) In 2016, we entered into a collaboration agreement with AbbVie for ARGX‑115 (ABBV‑151), targeting GARP in oncology (the AbbVie Collaboration Agreement). After completing IND‑enabling work, AbbVie exercised its option and assumed full responsibility for global development and commercialization. We are eligible for up to $625 million in potential development, regulatory and commercial milestones, plus tiered royalties from the mid‑single digits to lower teens. We also retain co‑promotion rights in the EEA and Switzerland. The agreement continues on a product‑by‑product basis until AbbVie’s payment obligations expire, and AbbVie may terminate the AbbVie Collaboration Agreement with prior notice. Trade Secret Protection In addition to patent protection, we rely on trade secret protection to ensure exclusivity for our proprietary information that is not amenable to, or that we do not consider appropriate for, patent protection, including, for example, certain aspects of our llama immunization and antibody affinity maturation approaches. However, trade secrets can be difficult to protect. Although we take steps to protect our proprietary information, including restricting access to our premises and our confidential information, as well as entering into agreements with our employees, consultants, advisors and potential collaborators, third parties may independently develop the same or similar proprietary information or may otherwise gain access to our proprietary information. As a result, we may be unable to meaningfully protect our trade secrets and proprietary information. Regulation Government authorities in the U.S., at the federal, state and local level, and in the EU and its Member States and other countries and jurisdictions, extensively regulate, among other things, the research, development, testing, manufacture, quality control, approval, packaging, storage, recordkeeping, labeling, advertising, promotion, distribution, marketing, post-approval monitoring and reporting, and import and export of pharmaceutical products, including biological products. In addition, many countries and jurisdictions regulate the pricing of pharmaceutical products. The processes for obtaining marketing approvals in the U.S. and in other countries and jurisdictions, along with subsequent compliance with applicable statutes and regulations and other regulatory authorities, require the expenditure of substantial personnel and financial resources, and breach of which can result in enforcement activity under civil, administrative and/or criminal law. Licensure and Regulation of Biologics in the U.S. In the U.S., biological products used for the prevention, treatment, or cure of a disease or condition in a human being are subject to regulation under the U.S. Federal Food, Drug, and Cosmetic Act (FDCA) and its implementing regulations. Biologics are approved for marketing under provisions of the Public Health Service Act (PHSA) via biologics license applications (BLAs). An applicant seeking approval to market and distribute a new biologic in the U.S. generally must satisfactorily complete each of the following steps: •preclinical laboratory tests, animal studies and formulation studies all performed in accordance with applicable requirements, including the GLPs; •submission to the FDA of an IND application for human clinical testing, which contains results of the preclinical tests, together with manufacturing information and analytical data and must become effective before human clinical trials may begin; •approval by an institutional review board (IRB) representing each clinical site before each clinical trial may be initiated; •performance of adequate and well-controlled human clinical trials to establish the safety, potency and purity of the product candidate for each proposed indication, in accordance with good clinical practices (GCPs); •preparation and submission to the FDA of a BLA for a biological product requesting marketing for one or more proposed indications, including submission of detailed information on the manufacture and composition of the product in clinical development and proposed labeling; 47 Table of Contents •one or more FDA inspections of the manufacturing facility or facilities, including those of third parties, at which the product, or components thereof, are produced to assess compliance with cGMP requirements and to assure that the facilities, methods and controls are adequate to preserve the product’s identity, potency, quality and purity; •FDA inspections of the clinical trial sites and/or sponsor to assure compliance with GCPs, and the integrity of clinical data in support of the BLA; •payment of user fees and securing FDA approval of the BLA and licensure of the new biological product; and •compliance with any post-approval requirements, including the potential requirement to implement a risk evaluation and mitigation strategy (REMS) and any post-approval studies required by the FDA. Human Clinical Trials in Support of a BLA Clinical trials typically are conducted in three sequential phases, but the phases may overlap or be combined. Additional clinical trials may be required after approval. •Phase 1 clinical trials are initially conducted in a limited population to test the product candidate for safety, including adverse effects, dose tolerance, absorption, metabolism, distribution, excretion and PD in healthy humans or, in patients. •Phase 2 clinical trials are generally conducted in a limited patient population to identify possible adverse effects and safety risks, evaluate the efficacy of the product candidate for specific targeted indications and determine dose tolerance and optimal dosage. Multiple Phase 2 clinical trials may be conducted by the sponsor to obtain information prior to beginning larger Phase 3 clinical trials. •Phase 3 clinical trials are undertaken within an expanded patient population to gather additional information about safety and effectiveness necessary to evaluate the overall benefit-risk relationship of the drug and to provide an adequate basis for physician labeling. A sponsor who wishes to conduct a clinical trial outside the U.S. may, but is not required to, obtain FDA clearance to conduct the clinical trial under an effective IND. If a foreign clinical trial is not conducted under an IND, the sponsor may submit data from the clinical trial to the FDA in support of the BLA so long as the clinical trial is well-designed and well-conducted in accordance with GCPs, including review and approval by an independent ethics committee, and the FDA is able to validate the clinical trial data through an onsite inspection, if necessary. In some cases, the FDA may approve a BLA for a product candidate but require the sponsor, or the sponsor may otherwise choose, to conduct additional clinical trials to further assess, amongst other things, the product candidate’s safety and effectiveness after approval. Such post-approval clinical trials are typically referred to as Phase 4 clinical trials. Failure to exhibit due diligence with regard to conducting required Phase 4 clinical trials could result in FDA enforcement, including withdrawal of approval for products. Review and Approval of a BLA The results of product candidate development, preclinical testing and clinical trials, including negative or ambiguous results as well as positive findings, are submitted to the FDA as part of a BLA requesting a license to market the product. The BLA also must contain extensive manufacturing information and detailed information on the composition of the product and proposed labeling as well as payment of a user fee, unless exempt. The FDA has 60 days after submission of the application to conduct an initial review to determine whether the BLA is sufficient to file based on the agency’s threshold determination that it is sufficiently complete to permit substantive review. If the FDA determines the BLA is not sufficiently complete, it will refuse to file the BLA. Once the submission has been filed, the FDA begins an in-depth review of the application. Under the goals agreed to by the FDA under the PDUFA, the FDA has 10 months from the filing date in which to complete its initial review of a standard application and respond to the applicant, and six months from the filing date for an application granted priority review. The FDA does not always meet its PDUFA goal dates and they may be extended in certain circumstances. After the FDA’s evaluation of the application and accompanying information, including the results of any necessary inspections, the FDA will issue an approval letter, or a complete response letter. An approval letter authorizes commercial marketing of the product with specific prescribing information for specific indications. Under the PHSA, the FDA may approve a BLA if it determines that the product is safe, pure and potent and the facility where the product will be manufactured meets standards designed to ensure that it continues to be safe, pure and potent. If the application is not approved, the FDA will issue a complete response letter, which will identify the deficiencies in the application. Sponsors that receive a complete response letter may resubmit to the FDA information addressing the issues identified by the 48 Table of Contents FDA, withdraw the application, or request a hearing. Even if a BLA is resubmitted with data and information addressing the deficiencies, the FDA may decide that the BLA does not satisfy the criteria for approval. The FDA may also refer the application to an advisory committee, consisting of independent experts, for review, evaluation and recommendation as to whether the application should be approved, particularly when applications present difficult or novel questions of safety or efficacy. The FDA is not bound by the recommendations of an advisory committee, but it considers such recommendations carefully when making decisions. If the FDA approves a new product, it may require testing and surveillance programs to monitor the product after commercialization, or impose other conditions, including distribution restrictions or other risk management mechanisms, including REMS, to help ensure that the benefits of the product outweigh the potential risks. REMS can include medication guides, communication plans for healthcare professionals, and/or elements to assure safe use. This can include, but are not limited to, special training or certification for prescribing or dispensing, dispensing only under certain circumstances, special monitoring, and the use of patent registries. The FDA may prevent or limit further marketing of a product based on the results of post-market studies or surveillance programs. After approval, many types of changes to the approved product, such as adding new indications, certain manufacturing changes, and additional labeling claims, are subject to further testing requirements and FDA review and approval. Expedited Development and Review Programs The FDA is authorized to designate products meeting certain criteria for expedited development and review programs. Even if a product qualifies for one or more of these programs, the FDA may later decide that the product no longer meets the conditions for qualification, or the time period for FDA review or approval may not be shortened. The FDA may designate a product for fast track review if it is intended, whether alone or in combination with one or more other products, for the treatment of a serious or life-threatening disease or condition, and demonstrates the potential to address unmet medical needs for such a disease or condition. For fast track products, sponsors may have more frequent interactions with the FDA and the FDA may initiate review of sections of a fast track product’s application before the application is complete (rolling review). The sponsor must also provide, and the FDA must approve, a schedule for the submission of the remaining information and the sponsor must pay applicable user fees. However, the FDA’s PDUFA clock for a rolling review application does not begin until the last section of the application is submitted. A product may be designated as a breakthrough therapy if it is intended, either alone or in combination with one or more other products, to treat a serious or life-threatening disease or condition and preliminary clinical evidence indicates that the product may demonstrate substantial improvement over existing therapies on one or more clinically significant endpoints, such as substantial treatment effects observed early in clinical development. The FDA may take certain actions with respect to breakthrough therapies, including holding meetings with the sponsor throughout the development process; providing timely advice to the product sponsor regarding development and approval; involving more senior staff in the review process; assigning a cross-disciplinary project lead for the review team; and taking other steps to design the clinical trials in an efficient manner. Breakthrough therapy designation also comes with all of the benefits of fast-track designation. The FDA may designate a product for priority review if it is a product that treats a serious condition and, if approved, would provide a significant improvement in safety or effectiveness. The FDA determines, on a case-by-case basis, whether the proposed product represents a significant improvement when compared with other available therapies. Significant improvement may be illustrated by evidence of increased effectiveness in the treatment of a condition, elimination or substantial reduction of a treatment-limiting product reaction, documented enhancement of patient compliance that may lead to improvement in serious outcomes, or evidence of safety and effectiveness in a new subpopulation. A priority designation is intended to direct overall attention and resources to the evaluation of such applications, and to shorten the FDA’s goal for taking action on a marketing application from 10 months to six months after accepting the application for filing. The FDA may grant accelerated approval to a product for a serious or life-threatening condition that provides meaningful therapeutic advantage to patients over existing treatments based upon a determination that the product has an effect on a surrogate endpoint that is reasonably likely to predict clinical benefit or on a clinical endpoint that can be measured earlier than an effect on irreversible morbidity or mortality (IMM) and that is reasonably likely to predict an effect on IMM or other clinical benefit (intermediate clinical endpoint), taking into account the severity, rarity, or prevalence of the condition and the availability or lack of alternative treatments. Products granted accelerated approval must meet the same statutory standards for safety and effectiveness as those granted traditional approval. For the purposes of accelerated approval, a surrogate endpoint is a marker, such as a laboratory measurement, radio- graphic image, physical sign, or other measure that is thought to predict clinical benefit but is not itself a measure of clinical benefit. Surrogate endpoints can often be measured more easily or more rapidly than clinical endpoints. An 49 Table of Contents intermediate clinical endpoint is a measurement of a therapeutic effect that is considered reasonably likely to predict the clinical benefit of a product, such as an effect on IMM. The accelerated approval pathway is most often used in settings in which the course of a disease is long and an extended period of time is required to measure the intended clinical benefit of a product, even if the effect on the surrogate or intermediate clinical endpoint occurs rapidly. Thus, accelerated approval has been used extensively in the development and approval of products for treatment of a variety of cancers in which the goal of therapy is generally to improve survival or decrease morbidity and the duration of the typical disease course requires lengthy and sometimes large clinical trials to demonstrate a clinical or survival benefit. The accelerated approval pathway is usually contingent on a sponsor’s agreement to conduct, in a diligent manner, a post-approval confirmatory clinical trial or studies to verify and describe the product’s clinical benefit. These confirmatory clinical trials must be completed with due diligence, and the FDA may require that the confirmatory clinical trial be designed, initiated, and/or fully enrolled prior to, or within a certain period following, approval. The FDA must also specify the conditions of any required post-approval clinical trial. Sponsors are required to submit progress reports for required post-approval studies, and the failure to conduct with due diligence a required post-approval clinical trial, including a failure to meet any required conditions specified by the FDA, or to submit timely reports, are prohibited acts under the FDCA. Failure to conduct required post-approval studies, or confirm a clinical benefit during post- marketing studies, would allow the FDA to withdraw the product from the market on an expedited basis. Unless otherwise informed by the FDA, all promotional materials for product candidates approved under accelerated approval are subject to prior review by the agency. Orphan Drug Designation and Exclusivity Orphan drug designation in the U.S. is designed to encourage sponsors to develop products intended for rare diseases or conditions. In the U.S., a rare disease or condition is statutorily defined as a condition that affects fewer than 200,000 individuals in the U.S. or that affects more than 200,000 individuals in the U.S. and for which there is no reasonable expectation that the cost of developing and making available the product for the disease or condition will be recovered from sales of the product in the U.S. An application for designation as an orphan product can be made any time prior to the filing of an application for approval to market the product. If the FDA grants orphan drug designation, the generic identity of the product and its potential orphan use are disclosed publicly by the FDA. Orphan drug designation qualifies a company for tax credits. Orphan drug designation does not convey any advantage in or shorten the duration of the regulatory review and approval process. If a product that has orphan drug designation subsequently receives the first FDA approval for the disease or condition for which it has such designation, the product is entitled to orphan drug exclusivity, which means that the FDA may not approve any other application to market the same drug for the same indication for seven years from the date of such approval, except in limited circumstances, such as a showing of clinical superiority to the product with orphan exclusivity by means of greater effectiveness, greater safety or providing a major contribution to patient care, or if the holder of the orphan exclusivity is unable to supply the market. Competitors, however, may receive approval of either a different product for the same indication or the same product for a different indication, which could be used off-label in the orphan indication. Orphan drug exclusivity also could block the approval of one of our products for seven years if a competitor obtains approval before we do for the same product, as defined by the FDA, for the same indication we are seeking approval, or if our product is determined to be contained within the scope of the approval of the competitor’s product for the same indication or disease. Post-Approval Regulation If regulatory approval for marketing of a product or new indication for an existing product is obtained, the sponsor will be required to comply with all post-approval regulatory requirements, including those that the FDA has imposed as part of the approval process. The sponsor will be required to report certain adverse reactions and production problems to the FDA, provide updated safety and efficacy information and comply with requirements concerning advertising and promotional labeling. Manufacturers and other parties involved in the drug supply chain for prescription drug and biological products must also comply with product tracking and tracing requirements and must notify the FDA of counterfeit, diverted, stolen and intentionally adulterated products or products that are otherwise unfit for distribution in the U.S. Manufacturers and certain of their subcontractors are required to register their establishments with the FDA and certain state agencies, and are subject to periodic unannounced inspections by the FDA and certain state agencies for compliance with ongoing regulatory requirements, including cGMPs. Accordingly, the sponsor and its third-party manufacturers must continue to expend time, money and effort in the areas of production and quality control to maintain compliance with cGMPs and other regulatory requirements. A biological product may also be subject to official lot release, meaning that the manufacturer is required to perform certain tests on each lot of the product before it is released for distribution. If the product is subject to official lot release, the manufacturer must submit samples of each lot, together with a release protocol showing a summary of the history of 50 Table of Contents manufacture of the lot and the results of all of the manufacturer’s tests performed on the lot, to the FDA. The FDA may in addition perform certain confirmatory tests on lots of some products before releasing the lots for distribution. Finally, the FDA will conduct laboratory research related to the safety, purity, potency and effectiveness of biological products. Any distribution of biological products and samples must comply with the U.S. Prescription Drug Marketing Act and the PHSA. Once approval of a BLA is granted, the FDA may revoke or suspend the approval if compliance with regulatory requirements and standards is not maintained or if problems occur after the product reaches the market. Later discovery of previously unknown problems with a product, including adverse events of unanticipated severity or frequency, or with manufacturing processes, or failure to comply with regulatory requirements, may result in revisions to the approved labeling to add new safety information; imposition of post-market studies or clinical trials to assess new safety risks; or imposition of distribution or other restrictions under a REMS program. FDA also has authority to require post-market studies, in certain circumstances, on reduced effectiveness of a product and may require labeling changes related to new reduced effectiveness information. Other potential consequences for a failure to maintain regulatory compliance include, among other things: •restrictions on the marketing or manufacturing of the product, complete withdrawal of the product from the market, or product recalls; •fines, untitled letters, or warning letters; •refusal of the FDA to approve pending applications or supplements to approved applications, or suspension or revocation of product license approvals; •product seizure or detention, or refusal to permit the import or export of products; or •injunctions or the imposition of civil or criminal penalties. Pediatric Studies and Exclusivity Under the Pediatric Research Equity Act of 2003, as amended (PREA), certain BLAs or supplements thereto must contain data that are adequate to assess the safety and effectiveness of the product for the claimed indications in all relevant pediatric sub-populations, and to support dosing and administration for each pediatric subpopulation for which the product is safe and effective. Sponsors must also submit an initial Pediatric Study Plan (PSP), within 60 days of an end-of-Phase 2 meeting or, if there is no such meeting, as early as practicable before the initiation of the Phase 3 or Phase 2/3 clinical trial. The initial PSPs must contain an outline of the proposed pediatric clinical trial or studies the applicant plans to conduct, including clinical trial objectives and design, any deferral or waiver requests and other information required by regulation. The applicant and the FDA must agree upon a final plan. The FDA or the applicant may request an amendment to the plan at any time. The FDA may, on its own initiative or at the request of the applicant, grant deferrals for submission of some or all pediatric data until after approval of the product for use in adults, or full or partial waivers from the pediatric data requirements. Unless otherwise required by regulation, PREA does not apply to a biologic for an indication for which orphan designation has been granted, except that PREA will apply to an original BLA for a new active ingredient that is orphan-designated if the biologic is a molecularly targeted cancer product intended for the treatment of an adult cancer and is directed at a molecular target that FDA determines to be substantially relevant to the growth or progression of a pediatric cancer. Pediatric exclusivity is another type of non-patent regulatory exclusivity in the U.S. and, if granted for a biologic, provides for the attachment of an additional six months of protection to the term of any existing regulatory exclusivity (i.e., reference product exclusivity and orphan drug exclusivity) that has at least 9 months left to expiration. This six- month exclusivity may be granted if a BLA sponsor submits reports of pediatric studies that fairly respond to a written request from the FDA for such studies, were conducted in accordance with commonly accepted scientific principles and protocols, and have been reported in accordance with filing requirements. Biosimilars and Exclusivity The Biologics Price Competition and Innovation Act (BPCIA) established a regulatory scheme authorizing the FDA to approve biosimilars and interchangeable biosimilars. Under the BPCIA, an applicant may submit an application for licensure of a biologic product that is “biosimilar to” or “interchangeable with” a previously approved biological product or “reference product.” For the FDA to approve a biosimilar product, it must find that the proposed biosimilar is highly similar to the reference product notwithstanding 51 Table of Contents minor differences in clinically inactive components and that there are no clinically meaningful differences between the product and the reference product in terms of safety, purity, or potency. For the FDA to approve a biosimilar product as interchangeable with a reference product, the agency must find that the biosimilar product is biosimilar to the reference product and that it can be expected to produce the same clinical results as the reference product in any given patient, and (for products administered multiple times) that the biologic and the reference biologic may be alternated or switched after one has been previously administered without increasing safety risks or risks of diminished efficacy relative to exclusive use of the reference biologic without such alternation or switch. Under the BPCIA, an application for a biosimilar product may not be submitted to the FDA until four years following the date of approval of the reference product. The FDA may not approve a biosimilar product until 12 years from the date on which the reference product was approved. Even if a product is considered to be a reference product eligible for exclusivity, another company could market a competing version of that product if the FDA approves a full BLA for such product containing the sponsor’s own preclinical data and data from adequate and well-controlled clinical trials to demonstrate the safety, purity and potency of their product. We note that patent positions may be available to preclude the introduction into commerce of such competing product independent of any FDA exclusivities. The BPCIA also created certain exclusivity periods for biosimilars approved as interchangeable products. Products deemed interchangeable by the FDA may be substituted by pharmacies as dictated by individual state law. U.S. Patent Term Restoration Depending upon the timing, duration, and specifics of FDA review and approval of our product candidates, some of our U.S. patents may be eligible for limited patent term extension under the Hatch-Waxman Act that permits restoration of the patent term of up to five years as compensation for patent term lost during the FDA regulatory review process. Patent-term restoration, however, cannot extend the remaining term of a patent beyond a total of 14 years from the product’s approval date, and only those claims covering such approved product, a method for using it or a method for manufacturing it may be extended. The patent-term restoration period is generally one-half the time between the effective date of an IND and the submission date of a BLA plus the time between the submission date of a BLA and the approval of that application, except that the review period is reduced by any time during which the applicant failed to exercise due diligence. Only one patent applicable to an approved biologic is eligible for the extension and the application for the extension must be submitted within 60 days of approval from FDA and prior to the expiration of the patent. The U.S. Patent and Trademark Office (USPTO), in consultation with the FDA, reviews and approves the application for any patent term extension or restoration. In the future, we may apply for restoration of patent term for our currently owned or licensed patents to add patent life beyond the current expiration date, depending on the expected length of the clinical trials and other factors involved in the filing of the relevant BLA. Regulation and Procedures Governing Approval of Medicinal Products in the European Union Similar to the U.S., the EU comprehensively regulates, among other things, the development, manufacturing, placing on the market, advertising, distribution, import and export of medicinal products. Particularly, the placing on the market of a medicinal product for human use in the EU requires a marketing authorization (MA). Main provisions governing medicinal products in the EU are Directive 2001/83/EC and Regulation (EC) No 726/2004 (each as amended). Regulation (EC) No 141/2000 and Regulation (EC) No. 847/2000 (each as amended) are also of particular relevance for orphan medicinal products. While directives need to be transposed into national law by member states of the EU (EU Member States) before they are applicable, regulations directly apply in the EU Member States once these have been enacted. The process governing approval of MA applications (MAA) for the placing on the market of medicinal products in the EU generally follows the same lines as in the U.S. It entails satisfactory completion of pharmaceutical development, pre- clinical trials and adequate and well-controlled clinical trials to establish the safety and efficacy of the medicinal product for each proposed indication. The EU also requires an application for authorization of clinical trials to relevant competent authorities and the submission of an MAA to the European Medicines Agency (EMA) or to competent authorities in EU member states and granting of such MA by the European Commission or relevant national authorities before the medicinal product can be marketed and sold in the EU or the relevant EU Member States. The below mentioned principles and rules generally apply within the EEA, i.e., the EU including Iceland, Liechtenstein and Norway. Clinical Trial Approval Both non-clinical and clinical data are generally required to support an MAA for a medicinal product in the EU. Non- clinical investigations are performed to demonstrate the health or environmental safety of new biological substances. Non-clinical (pharmaco-toxicological) investigations must generally be conducted in compliance with the principles of good laboratory practice (GLP) as set forth in EU Directive 2004/10/EC (as amended). 52 Table of Contents Clinical trials are comprehensively regulated in the EU under the Clinical Trials Regulation (EU) No 536/2014 (CTR), which entered into application on January 31, 2022, and gradually replaced the Clinical Trials Directive 2001/20/EC (CTD). As before, many of the CTR’s legal obligations are on the so-called sponsor, which is defined as the individual, company, institution, or organization that takes responsibility for the initiation, for the management and for setting up the financing of a clinical trial. The sponsor must obtain an authorization from the competent authority in the EU Member State(s) in which the clinical trial will be conducted as well as an approval from the competent national ethics committee in accordance with relevant national legislation in each of the relevant member states, before the commencement of such clinical trial. The CTR also imposes requirements, among others, regarding the conduct of a clinical trial (which must be conducted in accordance with the protocol and good clinical practice to generate acceptable data for MA submission), safety reporting of adverse events and reactions, changes to clinical trials, protection and informed consent of clinical trial subjects. Clinical trials conducted outside the EEA must follow the principles set forth in EU legislation if their results are to be submitted in an MAA in the EU. Orphan Designation and Exclusivity Regulations (EC) No. 141/2000 and No. 847/2000 (each as amended) provide that a product can be designated as an orphan medicinal product by the European Commission if its sponsor can establish: (i) that the product is intended for the diagnosis, prevention or treatment of a life-threatening or chronically debilitating condition, (ii) either (a) the prevalence of the condition is not more than five in ten thousand persons in the EU when the application is made, or (b) without incentives it is unlikely that the marketing of the product in the EU would generate sufficient return to justify the necessary investment in its development and (iii) there exists no satisfactory method of diagnosis, prevention, or treatment of the condition in question that has been authorized in the EU or, if such method exists, the product has to be of a significant benefit compared to products available for the condition. An orphan designation provides a number of benefits, including fee reductions and, regulatory assistance. If an MA is granted for an orphan medicinal product, this generally results in a ten-year period of market exclusivity for the approved orphan indication. It is, however, not possible to combine non-orphan and orphan indications within the same MA. Thus, for non-orphan indications treated with the same active pharmaceutical ingredient, a separate MA has to be sought. Alternatively, the orphan designation may be waived to allow for the addition of non-orphan indications to an existing MA. As a result, the approved medicinal product would no longer profit from the orphan designation’s benefits. During an orphan medicinal product’s market exclusivity period, neither the EMA, the European Commission nor the EU Member States can accept an application or grant an MA for a “similar medicinal product.” A “similar medicinal product”, i.e., a medicinal product containing a similar active substance or substances as contained in an authorized orphan medicinal product, and which is intended for the same therapeutic indication. The market exclusivity period for the authorized therapeutic indication may, however, be reduced to six years if, at the end of the fifth year, it is established that the product no longer meets the criteria for orphan designation. For orphan medicinal products intended for pediatric use, the market exclusivity period may be prolonged by additional two years if they are authorized with a pediatric indication based on the results from studies conducted under an EMA-approved pediatric investigation plan or if they are authorized without a pediatric indication but the results of the studies conducted under the EMA-approved pediatric investigation plan are reflected in the summary of product characteristic and, if appropriate, in the package leaflet. Market exclusivity may also be revoked in very select cases, such as if (i) it is established that a similar medicinal product is safer, more effective or otherwise clinically superior; (ii) the MA holder (MAH) for the authorized orphan medicinal product consents to the second orphan application; or (iii) the MAH for the authorized orphan medicinal product cannot supply sufficient quantities. Orphan designation must be requested before submitting an MAA and is reconfirmed during the MAA process. Orphan designation does not convey any advantage in, or shorten the duration of, the regulatory review and MA approval process. Marketing Authorization To obtain an MA for a medicinal product under the EU regulatory framework, an applicant must submit an MAA, either to the EMA using the centralized procedure or to competent authorities in the EU Member States using the other procedures (decentralized procedure, national procedure, or mutual recognition procedure). An MA may be granted only to an applicant established in the EU. Regulation (EC) No. 1901/2006 provides that prior to obtaining an MA in the EU, an applicant must demonstrate compliance with all measures included in an EMA-approved pediatric investigation plan, covering all subsets of the pediatric population, unless the EMA has granted a product-specific waiver, class waiver, or a deferral for one or more of the measures included in the pediatric investigation plan. The centralized procedure provides for the grant of a single MA by the European Commission that is valid for all EEA Member States. Pursuant to Regulation (EC) No. 726/2004 (as amended), the centralized procedure is compulsory for 53 Table of Contents specific products, including for medicines produced by certain biotechnological processes, products designated as orphan medicinal products, advanced therapy medicinal products (gene therapy, somatic cell therapy or tissue engineered products) and products with a new active substance indicated for the treatment of certain diseases, including products for the treatment of cancer and auto-immune diseases and other immune dysfunctions and neurodegenerative disorders. The centralized procedure is optional for certain other medicinal products. Under the centralized procedure, the EMA’s Committee for Medicinal Products for Human Use (CHMP) is responsible for conducting the assessment of a product to define its risk/benefit profile. The CHMP recommendation is then sent to the European Commission, which adopts a decision binding in all EEA Member States. Under the centralized procedure, the maximum timeframe for the evaluation of an MAA is 210 days, excluding clock stops when additional information or written or oral explanation is to be provided by the applicant in response to questions asked by the CHMP, which can considerably extend the 210 days. Accelerated evaluation (150 days excluding clock stops) may be granted by the CHMP in exceptional cases, when a medicinal product is of major interest from the point of view of public health and, in particular, from the viewpoint of therapeutic innovation. MAs have an initial validity for five years, in principle, and they may be renewed after five years on the basis of a reevaluation of the risk benefit balance by the EMA, or by the competent authority of the EU Member State. Once renewed, the MA is valid for an unlimited period, unless the European Commission or the competent authority decides, on justified grounds relating to pharmacovigilance, to proceed with one additional five-year renewal period. Any MA that is not followed by the placement of the medicinal product on the EU market or on the market of the authorizing EU Member State(s) within three years after authorization, or if the drug is removed from the market for three consecutive years, ceases to be valid. European Data and Market Exclusivity In the EU, innovative medicinal products, approved on the basis of a complete independent data package, qualify for eight years of data exclusivity upon MA and an additional two years of market exclusivity (for the more comprehensive protections applying to orphan medicinal products, please refer to “Item 4.B — Business overview — Orphan Designation and Exclusivity” above). The data exclusivity, if granted, prevents generic or biosimilar applicants from referencing the innovator’s preclinical and clinical trial data contained in the dossier of the reference product when applying for a generic or biosimilar MA in the EU, for a period of eight years from the date on which the reference product was first authorized in the EU. During the additional two-year period of market exclusivity, a generic or biosimilar MAA can be submitted, and the innovator’s data may be referenced, but no generic or biosimilar product can be marketed in the EU until the expiration of the market exclusivity period. The overall ten-year period will be extended to a maximum of 11 years if, during the first eight years of those 10 years, the MAH obtains an MA for one or more new therapeutic indications which, during the scientific evaluation prior to their authorization, are determined to bring a significant clinical benefit in comparison with currently approved therapies. There is no guarantee that a product will be considered by the EMA to be an innovative medicinal product, and products may not qualify for data exclusivity. Even if a product is considered to be an innovative medicinal product so that the innovator gains the prescribed period of data exclusivity, another company nevertheless could also market another version of the product if such company obtained an MA based on an MAA with a complete independent data package of pharmaceutical tests, preclinical tests and clinical trials. Regulatory Requirements after Marketing Authorization Following MA approval, the MAH is required to comply with a range of requirements applicable to the manufacturing, marketing, promotion and sale of the medicinal product. These include compliance with the EU’s stringent pharmacovigilance or safety reporting rules under Directive 2001/83/EC and Regulation (EU) 726/2004 (each as amended) and the associated guideline on good pharmacovigilance practices (as amended), pursuant to which post- authorization studies and additional monitoring obligations can be imposed. In addition, the manufacturing of authorized medicinal products, for which a separate manufacturer’s license is mandatory, must also be conducted in strict compliance with the principles of good manufacturing practice (GMP) set forth in Commission Directive 2017/1572 GMP and comparable requirements of other regulatory bodies in the EU, which mandate the methods, facilities and controls used in manufacturing, processing and packing of products to assure their safety and identity. Further, the wholesale distribution of authorized medicinal products requires a separate distribution license and must be conducted in strict compliance with good distribution practice standards. Finally, the marketing and promotion of authorized medicinal products is strictly regulated under Directive 2001/83/EC, (as amended) and as transposed into national laws. Potential consequences for a failure to maintain regulatory compliance mainly depend on the relevant regulations in the EU Member States, but are, for example, in Germany, similar to those in the U.S. Please refer to “Item 4.B — Business overview — Post-Approval Regulations” above. 54 Table of Contents Agreement on new EU Pharmaceutical Legislation On December 11, 2025, the EU legislative bodies agreed to overhaul, modernize, and streamline the existing general pharmaceutical legislation, including e.g., Directive 2001/83/EC, as well as Regulations (EC) No. 726/2004, No. 141/2000, or No. 1901/2006 (EU Pharmaceutical Legislation). This agreement is still subject to formal approval by the European Parliament and the Council of the EU, before being formally adopted. It is expected that the EU Pharmaceutical Legislation will become applicable in 2028. Although the final text has not yet been published, agreed key elements appear to include, among others, certain changes to the baseline marketing exclusivity periods, the streamlining of regulatory procedures as well as a broadening of the so-called “Bolar exemption”, which allows developers to undertake testing and to prepare for regulatory submissions before patent expiry. Regulation and Procedures Governing Approval of Medicinal Products in Japan In order to market any medical products in Japan, a company must comply with numerous and varying regulatory requirements regarding quality, safety and efficacy in the context, among other things, of clinical trials, marketing approval, commercial sales and distribution of products. A person who manufactures or markets medical products in Japan is subject to the supervision of the Ministry of Health, Labour and Welfare (MHLW), primarily under the Act on Securing Quality, Efficacy and Safety of Pharmaceuticals and Medical Devices (Pharmaceutical and Medical Devices Act). This entails the satisfactory completion of pharmaceutical development, preclinical studies and adequate and well- controlled clinical trials to establish the safety and efficacy of the medical product for each proposed indication. It also requires the filing of a notification of clinical trials with the Pharmaceuticals and Medical Devices Agency (Japan) (PMDA) and the obtaining of marketing approval from the relevant authorities before the product can be marketed and sold in the Japanese market. Business License Under the Pharmaceutical and Medical Devices Act, a company or individual must obtain a Marketing Authorization Holder (MAH) license from the MHLW to engage in the marketing or provision of medical products. This requirement applies to medical products that are either manufactured by the company itself outsourced to a third party for manufacturing or imported. To manufacture medical products for the Japanese market, a company must obtain a manufacturing license from the MHLW for each production facility. This license is separate from the marketing authorization and is required for both domestic and foreign manufacturing sites. Marketing Approval Under the Pharmaceutical and Medical Devices Act, it is generally required to obtain marketing approval from the MHLW for the marketing of each medical product. An application for marketing approval must be made through the PMDA, which implements a marketing approval review. Clinical Trial Under the Pharmaceutical and Medical Devices Act, it is required to file notification of clinical trials with the PMDA. The data of clinical trials and other pertinent data, which must be attached to an application for marketing approval, must be obtained in compliance with the standards established by the MHLW, such as GLPs and GCPs stipulated by the ministerial ordinances of the MHLW. Regulatory Requirements after Marketing Approval A MAH that has obtained marketing approval for a new pharmaceutical is subject to re-examination by the PMDA for a specified period after receiving marketing approval. Such re-examination period for VYVGART is stated to be 10 years after the marketing approval in January 2022. The purpose of this re-examination process is to ensure the safety and efficacy of a newly approved pharmaceutical by imposing on the MAH the obligation to gather clinical data for a certain period after the marketing approval was granted to enable the PMDA to re-examine the product. Results of use and other pertinent data must be attached to an application for a re-examination. An MAH that has obtained a marketing approval is also required to investigate, among other things, the results of use and to periodically report to the PMDA pursuant to the Pharmaceutical and Medical Devices Act. 55 Table of Contents Price Regulation Japan's public medical insurance systems cover virtually the entire Japanese population. The public medical insurance system, however, does not cover any medical product which is not listed on the National Health Insurance (NHI) price list published by the Minister of the MHLW. Accordingly, an MAH of medical products must first have a new medical product listed on the NHI price list to obtain coverage under the public medical insurance system. VYVGART was listed on the NHI price list in April 2022 and the price was adjusted in February 2024. VYVDURA was listed in April 2024. The NHI price of a medical product is determined either by price comparison of comparable medical products with necessary adjustments for innovation, usefulness or size of the market; or, in the absence of comparable medical products, by the cost calculation method, determined after considering of the opinion of the manufacturer. Prices on the NHI price list are subject to revision, generally once every year, based on the actual prices at which the medical products are purchased by medical institutions. Coverage, Pricing and Reimbursement Significant uncertainty exists as to the coverage and reimbursement status of any product candidates for which we may obtain regulatory approval. Even if our product candidates are approved for marketing, sales of such product candidates will depend, in part, on the extent to which third-party payors, including government health programs in the U.S. (such as Medicare and Medicaid), commercial health insurers, and managed care organizations, provide coverage and establish adequate reimbursement levels for such product candidates. Moreover, increasing efforts by governmental and third- party payors in the EU, the U.S. and other markets to cap or reduce healthcare costs may cause such organizations to limit both coverage and the level of reimbursement for newly approved products and, as a result, they may not cover or provide adequate payment for our product candidates. We expect to experience pricing pressures in connection with the sale of any of our product candidates due to the trend toward managed healthcare, the increasing influence of health maintenance organizations and additional legislative changes. The downward pressure on healthcare costs in general, particularly prescription drugs and surgical procedures and other treatments, has become very intense. As a result, increasingly high barriers are being erected to the entry of new products. In the U.S. and markets in other countries, patients generally rely on third-party payors to reimburse all or part of the costs associated with their treatment. Adequate coverage and reimbursement from governmental healthcare programs, such as Medicare and Medicaid, and commercial payors is critical to new product acceptance. Patients are unlikely to use any product candidates we may develop unless coverage is provided and reimbursement is adequate to cover a significant portion of the cost of such product candidates. Factors payors consider in determining reimbursement are based on whether the product is (i) a covered benefit under its health plan; (ii) safe, effective and medically necessary; (iii) appropriate for the specific patient; (iv) cost-effective; and (v) neither experimental nor investigational. The Medicare and Medicaid programs increasingly are used as models for how private payors and other governmental payors develop their coverage and reimbursement policies for drugs and biologics. Some third-party payors may require pre-approval of coverage for new or innovative devices or drug therapies before they will reimburse healthcare providers who use such therapies. It is difficult to predict at this time what third-party payors will decide with respect to the coverage and reimbursement for our product candidates. No uniform policy for coverage and reimbursement for drug products exists among third-party payors in the U.S. Therefore, coverage and reimbursement for drug products can differ significantly from payor to payor including formulary tier placement and utilization management requirements (if any). As a result, the coverage determination process is often a time-consuming and costly process that will require us to provide scientific and clinical support for the use of our products to each payor separately, with no assurance that coverage and adequate reimbursement will be applied consistently or obtained in the first instance. The position of a product on a formulary generally determines the co-payment that a patient will need to make to obtain the product and can strongly influence the adoption of a product by patients and physicians. Third-party payors may limit coverage to specific products on a formulary, which might not include all of the approved products for a particular indication. Additionally, a payor’s decision to provide coverage for a product does not imply that an adequate reimbursement rate will be approved or that cost-sharing will be acceptable for patients. Coverage policies and third-party reimbursement rates may change at any time. Even if favorable coverage and reimbursement status is attained for one or more of our products for which we or our collaborators receive marketing approval, less favorable coverage policies and reimbursement rates may be implemented in the future. Third-party payors are increasingly challenging the price and examining the medical necessity and cost-effectiveness of medical products and services and imposing controls to manage costs, especially drugs when an equivalent generic drug or a less expensive therapy is available. It is possible that a third-party payor may consider our product candidate and other therapies (in some cases even off-label treatments) as substitutable and only offer to reimburse patients for the less expensive product. Even if we show improved efficacy or improved convenience of administration with our product candidate, pricing of existing drugs may limit the amount we will be able to charge for our product candidate. These 56 Table of Contents payors may deny or revoke the reimbursement status of a given drug product or establish prices for new or existing marketed products at levels that are too low to enable us to realize an appropriate return on our investment in product development. If reimbursement is not available or is available only at limited levels, we may not be able to successfully commercialize our product candidates and may not be able to obtain a satisfactory financial return on products that we may develop. In Mainland China, VYVGART IV has been included in the National Reimbursement Drug List (NRDL) for the treatment of adults with gMG who are AChR-AB+ after going through price negotiations with the National Healthcare Security Administration (NHSA) since January 2024, which means that the price of this drug can be (partly) reimbursed by the social security program of Mainland China for the treatment of this indication in accordance with relevant rules within certain period. According to the current regulations of Mainland China, if we want our products in addition to VYVGART IV to be included in the NRDL or want VYVGART to be included in the NRDL for the treatment of other indications, we will need to go through price negotiations with the NHSA, for which purpose we will likely need to significantly reduce their prices. Although the inclusion of our products in the NRDL may increase the demand for the relevant products, our potential revenue from the sales of these products may still decrease as a result of lower prices. Furthermore, rules and regulations regarding reimbursement change frequently, in some cases at short notice, and we believe that changes in these rules and regulations are likely. Outside the U.S., we will face challenges in ensuring obtaining adequate coverage and payment for any product candidates we may develop. Pricing of prescription pharmaceuticals is subject to governmental control in many countries. In order to secure coverage and reimbursement for any product that might be approved for sale, we have needed and may need to conduct expensive pharmacoeconomic studies in order to demonstrate the medical necessity and cost-effectiveness of the product, and the cost of these studies would be in addition to the costs required to obtain FDA or other comparable marketing approvals. Conducting such studies could be expensive, involve additional risk and result in delays in our commercialization efforts. Even after pharmacogenomic studies are conducted, product candidates may not be considered medically necessary or cost- effective. A decision by a third-party payor not to cover any product candidates we may develop could reduce physician utilization of such product candidates once approved and have a material adverse effect on our sales, results of operations and financial condition. Third-party reimbursement and coverage may not be adequate to enable us to maintain price levels sufficient to realize an appropriate return on our investment in product development. The insurance coverage and reimbursement status of newly approved products for orphan diseases is particularly uncertain, and failure to obtain or maintain adequate coverage and reimbursement for any such product candidates could limit our ability to generate revenue. As noted above, in the U.S., we plan to have various programs to help patients afford our products, including patient assistance programs and co-pay coupon programs for eligible patients. More specifically, patients can enroll into MY VYVGART PATH™, a patient support program that provides personalized support from a nurse case manager and committed support team. In addition to providing support on questions on the treatment and on navigating the insurance process, the program provides a VYVGART Co-pay Program to eligible patients, aids in referring patients to charitable foundations that may be able to help with out-of-pocket costs and informs patients of financial assistance programs that may be available. The containment of healthcare costs also has become a priority of U.S. federal, state and international governments and the prices of pharmaceuticals have been a focus in this effort. Governments have shown significant interest in implementing cost-containment programs, including price controls, restrictions on reimbursement and requirements for substitution of generic products. Net prices for drugs may be reduced by mandatory discounts or rebates required by government healthcare programs or private payors and by any future relaxation of laws that presently restrict imports of drugs from countries where they may be sold at lower prices than in the U.S. Increasingly, third-party payors are requiring that drug companies provide them with predetermined discounts from list prices and are challenging the prices charged for medical products. We cannot be sure that reimbursement will be available for any future product candidate that we commercialize and, if reimbursement is available, the level of reimbursement. In addition, many pharmaceutical manufacturers must calculate and report certain price reporting metrics to the government, such as average sales price and best price. Penalties may apply in some cases when such metrics are not submitted accurately and timely. Adoption of price controls and cost-containment measures, and adoption of more restrictive policies in jurisdictions with existing controls and measures, could further limit our potential revenue from the sale of any products for which we may obtain approval. The delivery of healthcare in the EU, including the establishment and operation of health services and the pricing and reimbursement of medicinal products, is almost exclusively governed by national laws, rather than EU legislation. National governments and health service providers have different priorities and approaches to the delivery of healthcare and the pricing and reimbursement of products in that context. Therefore, in the EU, pricing and reimbursement schemes vary widely from EU Member State to another. Some EU Member States provide that products may be marketed only after a reimbursement price has been agreed. Some EU Member States may require the completion of additional studies that compare the cost-effectiveness of a particular product candidate to currently available therapies (so called health technology assessments) in order to obtain reimbursement or pricing approval. EU Member States may approve a specific price for a product or may instead adopt a system of direct or indirect controls on the profitability of the company placing the medicinal product on the market. Other EU Member States allow companies to fix their own prices for products but monitor and control prescription volumes and issue guidance to physicians to limit prescriptions. 57 Table of Contents Recently, many EU Member States have increased the amount of discounts required on medicinal products and these efforts could continue as Member States attempt to further manage healthcare expenditures. For example, Germany introduced a specific discount on certain combination products with new active ingredients. The downward pressure on healthcare costs in general, particularly medicinal prescription products, has become intense. As a result, increasingly high barriers are being erected to the entry of new products. Political, economic and regulatory developments may further complicate pricing negotiations, and pricing negotiations may continue after reimbursement has been obtained. Reference pricing used by various EU Member States and parallel trade (arbitrage between low-priced and high-priced Member States) can further reduce prices. Special pricing and reimbursement rules may apply to orphan medicinal products. Inclusion of orphan drugs in reimbursement systems tend to focus on the medical usefulness, need, quality and economic benefits to patients and the healthcare system as for any drug. Acceptance of any medicinal product for reimbursement may come with cost, use and often volume restrictions, which again can vary by country. In addition, results-based rules of reimbursement may apply. There can be no assurance that any EU Member State that has price controls or reimbursement limitations for pharmaceutical products will allow favorable reimbursement and pricing arrangements for any of our products, if approved in those countries. Historically, products launched in the EU do not follow price structures of the U.S. and generally prices tend to be significantly lower. The above underlines that, outside the U.S., international operations are generally subject to extensive governmental price controls and other market regulations, and we believe the increasing emphasis on cost-containment initiatives in Europe, Canada and other countries has and will continue to put pressure on the pricing and usage of our product candidates. In many countries, the prices of medical products are subject to varying price control mechanisms as part of national health systems. Other countries allow companies to fix their own prices for medical products but monitor and control company profits. Additional foreign price controls or other changes in pricing regulation could restrict the amount that we are able to charge for our product candidates. Accordingly, in markets outside the U.S., the reimbursement for our products may be reduced compared with the U.S. and may be insufficient to generate commercially reasonable revenue and profits. Government Pricing and Reimbursement Programs for Marketed Drugs in the U.S. Medicaid, the 340B Drug Pricing Program, and Medicare Federal law requires that a pharmaceutical manufacturer, as a condition of having its drug and biological products receive federal reimbursement under Medicaid and Medicare Part B, must pay rebates to state Medicaid programs for all units of its covered outpatient drugs dispensed to Medicaid beneficiaries and paid for by a state Medicaid program under either a fee-for-service arrangement or through a managed care organization. This federal requirement is effectuated through a Medicaid drug rebate agreement between the manufacturer and the Secretary of U.S. Department of Health and Human Services (HHS). The Centers for Medicare & Medicaid Services (CMS) administers the Medicaid drug rebate agreements, which provide, among other things, that the drug manufacturer will pay rebates to each state Medicaid agency on a quarterly basis and report certain price information on a monthly and quarterly basis. The rebates are based on prices reported to CMS by manufacturers for their covered outpatient drugs, including average manufacturer price (AMP) and best price. Effective January 1, 2024, the Medicaid total rebate amount is no longer capped at 100% of a covered outpatient drug’s AMP, which means that a manufacturer could pay a total rebate amount on a unit of the drug that is greater than the average price the manufacturer receives for the drug. The terms of participation in the Medicaid drug rebate program impose an obligation to correct the prices reported in previous quarters, as may be necessary. Any such corrections could result in additional or lesser rebate liability, depending on the direction of the correction. In addition to retroactive rebates, if a manufacturer were found to have knowingly submitted false information to the government, federal law provides for civil monetary penalties for failing to provide required information, late submission of required information, and false information. A manufacturer must also participate in a federal program known as the 340B drug pricing program in order for federal funds to be available to pay for the manufacturer’s drug and biological products under Medicaid and Medicare Part B. Under this program, the participating manufacturer agrees to charge certain safety net healthcare providers no more than an established discounted price for its covered outpatient drugs. The formula for determining the discounted price is defined by statute and is based on the AMP and the unit rebate amount as calculated under the Medicaid drug rebate program, discussed above. Manufacturers are required to report pricing information to the Health Resources and Services Administration on a quarterly basis. The Health Resources and Services Administration has also issued regulations relating to the calculation of the ceiling price as well as imposition of civil monetary penalties for each instance of knowingly and intentionally overcharging a 340B covered entity. Federal law also requires that manufacturers report data on a quarterly basis to CMS regarding the pricing of drugs that are separately reimbursable under Medicare Part B. These are generally drugs and biologics, such as injectable products, that are administered incident to a physician service and are not generally self-administered. The pricing information submitted by manufacturers is the basis for reimbursement to physicians and suppliers for drugs covered under Medicare Part B. Under the Inflation Reduction Act (IRA), manufacturers are also required to provide quarterly rebates for certain 58 Table of Contents single-source drugs and biologics (including biosimilars) covered under Medicare Part B with prices that increase faster than the rate of inflation. This requirement started on January 1, 2023 for drugs approved on or before December 1, 2020 and begins six quarters after a drug is first marketed for all other drugs. As with the Medicaid drug rebate program, federal law provides for civil monetary penalties for failing to provide required information, late submission of required information, and false information. Additionally, the Infrastructure Investment and Jobs Act added a requirement, effective January 1, 2023, for manufacturers of certain single-source drugs (including biologics and biosimilars) separately paid for under Medicare Part B for at least 18 months and marketed in single-dose containers or packages (known as refundable single-dose containers or single-use package drugs) to provide annual refunds for any portions of the dispensed drug that are unused and discarded if those unused or discarded portions exceed an applicable percentage defined by statute or regulation. Manufacturers will be subject to periodic audits and those that fail to pay refunds for their refundable single-dose containers or single-use package drugs shall be subject to civil monetary penalties. Medicare Part D provides prescription drug benefits for seniors and people with disabilities. Beginning in 2025, the IRA eliminates the coverage gap phase and associated manufacturer discounts under Medicare Part D, significantly lowers the enrollee maximum out-of-pocket cost and establishes a new manufacturer discount program, which requires 10% discounts in the initial phase, and 20% discounts in the catastrophic phase. Although these discounts represent a lower percentage of enrollees’ costs than coverage gap discounts, the new manufacturer contribution during the catastrophic phase could be considerable for certain high-cost drugs and the total contributions by manufacturers to a Part D enrollee’s drug expenses may exceed those currently provided. The IRA also requires manufacturers to provide annual Medicare Part D rebates for single-source drugs and biological products with prices that increase faster than the rate of inflation. The IRA also allows HHS to directly negotiate the selling price of a statutorily specified number of drugs and biologics each year that CMS reimburses under Medicare Part B and Part D. Only high-expenditure single-source biologics that have been approved for at least 11 years (7 years for single-source drugs) can qualify for negotiation, with the negotiated price taking effect two years after the selection year. In July 2025, Congress expanded the IRA’s orphan drug exclusion to protect from selection drugs that are indicated only for orphan indications, as well as to extend the time before an orphan drug may be selected if it is later approved for a non-orphan indication. Negotiations for Medicare Part D products began in 2023 with the negotiated price taking effect in 2026, and negotiations for Medicare Part B products will begin in 2026 with the negotiated price taking effect in 2028. U.S. Federal Contracting and Pricing Requirements Manufacturers are also required to make their covered drugs, which are generally drugs approved under NDAs or BLAs, available to authorized users of the Federal Supply Schedule (FSS) of the General Services Administration. The law also requires manufacturers to offer deeply discounted FSS contract pricing for purchases of their covered drugs by the Department of Veterans Affairs, the Department of Defense, the Coast Guard, and the Public Health Service (including the Indian Health Service) in order for federal funding to be available for reimbursement or purchase of the manufacturer’s drugs under certain federal programs. FSS pricing to those four federal agencies for covered drugs must be no more than the Federal Ceiling Price (FCP), which is at least 24% below the Non-Federal Average Manufacturer Price (Non-FAMP) for the prior year. The Non-FAMP is the average price for covered drugs sold to wholesalers or other middlemen, net of any price reductions. The accuracy of a manufacturer’s reported Non-FAMPs, FCPs, or FSS contract prices may be audited by the government. Among the remedies available to the government for inaccuracies is recoupment of any overcharges to the four specified federal agencies based on those inaccuracies. If a manufacturer were found to have knowingly reported false prices, in addition to other penalties available to the government, the law provides for significant civil monetary penalties per incorrect item. Finally, manufacturers are required to disclose in FSS contract proposals all commercial pricing that is equal to or less than the proposed FSS pricing, and subsequent to award of an FSS contract, manufacturers are required to monitor certain commercial price reductions and extend commensurate price reductions to the government, under the terms of the FSS contract Price Reductions Clause. Among the remedies available to the government for any failure to properly disclose commercial pricing and/or to extend FSS contract price reductions is recoupment of any FSS overcharges that may result from such omissions. Healthcare Law and Regulation Healthcare providers and third-party payors play a primary role in the recommendation and prescription of pharmaceutical products that are granted marketing approval. Our current and future arrangements with providers, researchers, consultants, third-party payors and customers are subject to broadly applicable federal and state fraud and abuse, anti-kickback, false claims, transparency and patient privacy laws and regulations and other healthcare laws and regulations that may constrain our business and/or financial arrangements. Restrictions under applicable federal and state healthcare laws and regulations include, without limitation, the following: 59 Table of Contents •the U.S. federal Anti-Kickback Statute (AKS) prohibits, among other things, persons and entities from knowingly and willfully soliciting, receiving, offering, or paying remuneration, directly or indirectly, in cash or in kind, to induce or reward either the referral of an individual for, or the purchase, lease, order or recommendation of, any good facility, item, or service, for which payment may be made, in whole or in part, under a federal healthcare program such as Medicare and Medicaid. This statute has been interpreted to apply to arrangements between pharmaceutical manufacturers on the one hand and prescribers, purchasers formulary managers and other persons and entities on the other. Although there are a number of statutory exceptions and regulatory safe harbors protecting certain activities from prosecution, the exceptions and safe harbors are drawn narrowly, and arrangements may be subject to scrutiny or penalty if they do not fully satisfy all elements of an available exception or safe harbor. A person or entity can be found guilty of violating the AKS without actual knowledge of the statute or specific intent to violate it. In addition, the government may assert that a claim including items or services resulting from a violation of the AKS constitutes a false or fraudulent claim for purposes of the federal False Claims Act or federal civil money penalties statute. Violations of the AKS carry potentially significant civil and criminal penalties, including imprisonment, fines, administrative civil monetary penalties, and exclusion from participation in federal healthcare programs. •the U.S. federal false claims and civil monetary penalties laws, including the civil False Claims Act and federal civil monetary penalty laws, which, among other things, impose criminal and civil penalties, including through civil whistleblower or qui tam actions, against individuals or entities for knowingly presenting, or causing to be presented, to the U.S. federal government, claims for payment or approval that are false or fraudulent, knowingly making, using or causing to be made or used, a false record or statement material to a false or fraudulent claim or obligation to pay or transmit money to the federal government, or from knowingly making a false statement to avoid, decrease or conceal an obligation to pay money to the U.S. federal government. In addition, the government may assert that a claim including items and services resulting from a violation of the AKS constitutes a false or fraudulent claim for purposes of the False Claims Act. Manufacturers can be held liable under the False Claims Act even when they do not submit claims directly to government payors if they are deemed to “cause” the submission of false or fraudulent claims. The False Claims Act also permits a private individual acting as a “whistleblower” to bring qui tam actions on behalf of the federal government alleging violations of the False Claims Act and to share in any monetary recovery. When an entity is determined to have violated the federal civil False Claims Act, the government may impose civil fines and penalties for each false claim, plus treble damages, and exclude the entity from participation in Medicare, Medicaid and other federal healthcare programs; •the U.S. federal Health Insurance Portability and Accountability Act of 1996 (HIPAA) which imposes criminal and civil liability for, among other things, knowingly and willfully executing, or attempting to execute, a scheme to defraud any healthcare benefit program, or obtaining by means of false or fraudulent pretenses, representations, or promises, any of the money or property owned by, or under the custody or control of, any healthcare benefit program, regardless of the pay (e.g., public or private) or knowingly and willfully falsifying, concealing or covering up a material fact or making any materially false statement, in connection with the delivery of, or payment for, healthcare benefits, items or services relating to healthcare matters; similar to the AKS, a person or entity does not need to have actual knowledge of the statute or specific intent to violate it in order to have committed a violation; •HIPAA, as amended by the Health Information Technology for Economic and Clinical Health Act of 2009 (HITECH) and its implementing regulations, and as amended again by the Omnibus Rule in 2013, which imposes certain obligations, including mandatory contractual terms, with respect to safeguarding the privacy, security and transmission of individually identifiable health information without appropriate authorization by covered entities subject to the Final HIPAA Omnibus Rule, i.e., certain covered health plans, healthcare clearinghouses and healthcare providers, as well as their business associates, those independent contractors or agents of covered entities that perform certain services for or on their behalf involving the use or disclosure of individually identifiable health information. HITECH also created new tiers of civil monetary penalties, amended HIPAA to make civil and criminal penalties directly applicable to business associates and possibly other persons, and gave state attorneys general new authority to file civil actions for damages or injunctions in federal courts to enforce the federal HIPAA laws and seek attorneys’ fees and costs associated with pursuing federal civil actions; •the federal transparency requirements known as the federal Physician Payments Sunshine Act, under the Patient Protection and Affordable Care Act, as amended by the Health Care and Education Reconciliation Act of 2010 (collectively, the ACA), which requires certain manufacturers of drugs, devices, biologics and medical supplies to report annually to CMS information related to payments and other transfers of value made by that entity to physicians (currently defined to include doctors, dentists, optometrists, podiatrists and chiropractors), certain non-physician providers such as physician assistants and nurse practitioners and teaching hospitals, as well as ownership and investment interests held by physicians and their immediate family members. Failure to submit required information may result in civil monetary penalties for all payments, transfers of value or ownership or investment interests that are not timely, accurately, and completely reported in an annual submission; •federal government price reporting laws, which require us to calculate and report complex pricing metrics in an accurate and timely manner to government programs; 60 Table of Contents •federal consumer protection and unfair competition laws, which broadly regulate marketplace activities and activities that potentially harm consumers; •analogous state and local laws and regulations, including: state anti-kickback and false claims laws; state laws that require pharmaceutical companies to comply with the pharmaceutical industry’s voluntary compliance guidelines and the relevant compliance guidance promulgated by the U.S. federal government, or otherwise restrict payments that may be made to healthcare providers and other potential referral sources; state and local laws that require the licensure of sales representatives; state laws that require drug manufacturers to report information related to payments and other transfers of value to physicians and other healthcare providers or marketing expenditures and pricing information; state laws governing the privacy and security of health information in certain circumstances, many of which differ from each other in significant ways and may not have the same effect; and state laws related to insurance fraud in the case of claims involving private insurers; and •EU, UK and other foreign law equivalents, including reporting requirements detailing interactions with and payments to healthcare providers and data privacy and security laws and regulations that may be more stringent than those in the U.S. State and foreign laws, including for example the EU General Data Protection Regulation (GDPR), also govern the privacy and security of health information in some circumstances, many of which differ from each other in significant ways and often are not preempted by HIPAA, thus complicating compliance efforts. There are ambiguities as to what is required to comply with these state requirements and if we fail to comply with an applicable state law requirement, we could be subject to penalties. We have and will continue to spend substantial time and money to ensure that our business arrangements with third parties comply with applicable healthcare laws and regulations. Recent healthcare reform legislation has strengthened these federal and state healthcare laws. Because of the breadth of these laws and the narrowness of the statutory exceptions and safe harbors available, it is possible that some of our business activities could be subject to challenge under one or more of such laws. Other laws that may affect our ability to operate include: •the anti-inducement law prohibits, among other things, the offering or giving of remuneration, which includes, without limitation, any transfer of items or services for free or for less than fair market value (with limited exceptions), to a Medicare or Medicaid beneficiary that the person know or should know is likely to influence the beneficiary’s selection of a particular supplier of items or services reimbursable by a federal or state governmental program; and •European and other foreign law equivalents of each of the laws, including reporting requirements detailing interactions with and payments to healthcare providers. In the U.S., to help patients afford our approved product, we may utilize programs to assist them, including patient assistance programs and co-pay coupon programs for eligible patients. Government enforcement agencies have shown increased interest in pharmaceutical companies’ product and patient assistance programs, including reimbursement support services, and a number of investigations into these programs have resulted in significant civil and criminal settlements. In addition, at least one insurer has directed its network pharmacies to no longer accept co-pay coupons for certain specialty drugs the insurer identified. Our co-pay coupon programs could become the target of similar insurer actions. In addition, in November 2013, the CMS issued guidance to the issuers of qualified health plans sold through the ACA’s marketplaces encouraging such plans to reject patient cost-sharing support from third parties and indicating that the CMS intends to monitor the provision of such support and may take regulatory action to limit it in the future. The CMS subsequently issued a rule requiring individual market qualified health plans to accept third-party premium and cost-sharing payments from certain government-related entities. In September 2014, the Office of the Inspector General of the HHS issued a Special Advisory Bulletin warning manufacturers that they may be subject to sanctions under the AKS and/or civil monetary penalty laws if they do not take appropriate steps to exclude Part D beneficiaries from using co-pay coupons. Accordingly, companies exclude these Part D beneficiaries from using co-pay coupons. Additionally, certain third-party payors are modifying benefit designs based on the availability of manufacturer cost-sharing assistance (e.g., copay accumulator or maximizer programs). Following a federal district court decision vacating the provisions of the 2021 Notice of Benefit and Payment Parameter final rule that provided health plans with discretion whether to include manufacturer assistance toward the cost-sharing limit, CMS stated its intent to address this issue in future rulemaking. It is possible that changes in insurer policies regarding co-pay coupons and/or the introduction and enactment of new legislation or regulatory action could restrict or otherwise negatively affect these patient support programs, which could result in fewer patients using affected products, and therefore could have a material adverse effect on our sales, business, and financial condition. 61 Table of Contents Third-party patient assistance programs that receive financial support from companies have become the subject of enhanced government and regulatory scrutiny. The Office of the Inspector General of the HHS has established guidelines that suggest that it is lawful for pharmaceutical manufacturers to make donations to charitable organizations who provide co-pay assistance to Medicare patients, provided that such organizations, among other things, are bona fide charities, are entirely independent of and not controlled by the manufacturer, provide aid to applicants on a first-come basis according to consistent financial criteria and do not link aid to use of a donor’s product. However, donations to patient assistance programs have received some negative publicity and have been the subject of multiple government enforcement actions, related to allegations regarding their use to promote branded pharmaceutical products over other less costly alternatives. Specifically, in recent years, there have been multiple settlements resulting out of government claims challenging the legality of their patient assistance programs under a variety of federal and state laws. It is possible that we may make grants to independent charitable foundations that help financially needy patients with their premium, co-pay, and co-insurance obligations. If we choose to do so, and if we or our vendors or donation recipients are deemed to fail to comply with relevant laws, regulations or evolving government guidance in the operation of these programs, we could be subject to damages, fines, penalties, or other criminal, civil, or administrative sanctions or enforcement actions. We cannot ensure that our compliance controls, policies, and procedures will be sufficient to protect against acts of our employees, business partners, or vendors that may violate the laws or regulations of the jurisdictions in which we operate. Regardless of whether we have complied with the law, a government investigation could impact our business practices, harm our reputation, divert the attention of management, increase our expenses, and reduce the availability of foundation support for our patients who need assistance. Violations of these laws or any future enacted laws can subject us to criminal, civil and administrative sanctions including monetary penalties, damages, fines, disgorgement, individual imprisonment and exclusion from participation in government funded healthcare programs, such as Medicare and Medicaid, additional reporting requirements and oversight if we become subject to a corporate integrity agreement or similar agreement to resolve allegations of non- compliance with these laws, reputational harm, and we may be required to curtail or restructure our operations. Moreover, we expect that there will continue to be federal and state laws and regulations, proposed and implemented, that could impact our future operations and business. Because of the breadth of these laws and the narrowness of the statutory exceptions and safe harbors available, it is possible that some of our business activities could be subject to challenge under one or more of such laws. Ensuring that our internal operations and future business arrangements with third parties comply with applicable healthcare laws and regulations will involve substantial costs. It is possible that governmental authorities will conclude that our business practices do not comply with current or future statutes, regulations, agency guidance or case law involving applicable fraud and abuse or other healthcare laws and regulations. If our operations are found to be in violation of any of the laws described above or any other governmental laws and regulations that may apply to us, we may be subject to significant penalties, including administrative, civil and criminal penalties, damages, fines, disgorgement, the exclusion from participation in federal and state healthcare programs, individual imprisonment, reputational harm, and the curtailment or restructuring of our operations, as well as additional reporting obligations and oversight if we become subject to a corporate integrity agreement or other agreement to resolve allegations of non-compliance with these laws. Further, defending against any such actions can be costly and time-consuming, and may require significant financial and personnel resources. Therefore, even if we are successful in defending against any such actions that may be brought against us, our business may be impaired. If any of the physicians or other providers or entities with whom we expect to do business are found to not be in compliance with applicable laws, they may be subject to criminal, civil or administrative sanctions, including exclusions from government funded healthcare programs and imprisonment. If any of the above occur, our ability to operate our business and our results of operations could be adversely affected. Healthcare Reform In the U.S., the EU and other foreign jurisdictions, there have been a number of legislative and regulatory changes to the healthcare systems that could affect our future results of operations. In particular, there have been and continue to be a number of initiatives at the U.S. federal and state levels that seek to reduce healthcare costs and improve the quality of healthcare. For example, the ACA, effective since March 2010, is a sweeping law intended to broaden access to health insurance, reduce or constrain the growth of healthcare spending, enhance remedies against fraud and abuse, add new transparency requirements for the healthcare and health insurance industries, impose new taxes and fees on the health industry and impose additional health policy reforms. Healthcare reforms that have been adopted, and that may be adopted in the future, could result in further reductions in coverage and levels of reimbursement for pharmaceutical products, increases in rebates payable under U.S. government rebate programs and additional downward pressure on pharmaceutical product prices. As discussed above, in August 2022, the IRA was enacted codifying, among other things: a Medicare drug price negotiation program, under which HHS directly negotiates the selling price of statutorily specified number of Part B and Part D drugs and biologics each year; inflation rebates which penalizes drug manufacturers that increase prices of Medicare Part B and Part D drugs at a rate greater than the rate of inflation; and a redesign of the Part D benefit. The IRA permits the Secretary of HHS to implement many of these provisions through guidance, as opposed to regulation, for the initial years. Manufacturers that fail to comply with the IRA may be subject to various penalties, including civil monetary penalties. The IRA also 62 Table of Contents extends enhanced subsidies for individuals purchasing health insurance coverage in ACA marketplaces through plan year 2025. To date, none of the legislative attempts to extend the subsidies has been enacted. These IRA provisions began taking effect progressively starting in 2023, although certain policies have been subject to legal challenges. For example, the provisions related to the negotiation of selling prices of high-expenditure single-source drugs and biologics have been challenged in multiple lawsuits. Additionally, we cannot predict whether the U.S. Congress will further amend the IRA or if the government will adopt new or different interpretations of the law in future guidance or rulemaking. However, at this time, the Trump administration is continuing to implement the IRA and to defend the law in litigation. While it is unclear how the IRA will be implemented in the future and the outcome of the litigation, it will likely have a significant impact on the pharmaceutical industry. In addition, the Trump administration has taken several steps to try to align U.S. drug prices with drug prices in other countries through an approach known as most favored nation (MFN) pricing. For example, on May 12, 2025, the current Presidential administration published an executive order which, among other actions, instructed HHS to communicate MFN price targets. The executive order also directed certain steps if “significant progress towards [MFN] pricing . . . is not delivered.” On July 31, 2025, the U.S. President issued letters to 17 pharmaceutical companies (not including argenx), calling on those manufacturers and “every manufacturer” to take the following steps within 60 days: extend MFN pricing to Medicaid for all of their existing drugs; guarantee Medicare, Medicaid, and commercial payors receive MFN pricing for newly-launched drugs; return increased revenues abroad to American patients and taxpayers; and participate in direct-to-consumer or direct-to-business distribution models to provide “high-volume, high rebate” drugs at MFN pricing. Certain manufacturers have entered into direct agreements with the government. On November 6, 2025, CMS announced the GENErating cost Reductions fOr U.S. Medicaid (GENEROUS) Model under its Center for Medicare and Medicaid Innovation authority (CMMI). The GENEROUS Model is a voluntary model that tests the impact of CMS-facilitated supplemental rebate agreements that align the Medicaid net price with a defined MFN price. In December 2025, CMS issued the Global Benchmark for Efficient Drug Pricing (GLOBE) Model and Guarding U.S. Medicare Against Rising Drug Costs (GUARD) Model proposed rules under its Center for Medicare and Medicaid Innovation authority. The GLOBE and GUARD models would require manufacturers to pay additional rebates for certain drugs based on the difference between the Medicare price and the price in market basket countries. CMS proposes that the agency would apply the new rebate requirement to utilization by approximately 25% of Medicare Part B fee-for-service enrollees (under GLOBE) and 25% of Medicare Part D enrollees (under GUARD). It is uncertain if these proposed rules will be finalized and if they are, how they will impact our business. Additionally, in Congress, there are pending legislative proposals that, if enacted, would require MFN pricing in certain healthcare programs. We cannot predict if any of these legislative proposals will be enacted, how they would be implemented, and how they could impact our business. We expect that additional U.S. federal healthcare reform measures will be adopted in the future, any of which could limit the amounts that the U.S. federal government will pay for healthcare products and services, which could result in reduced demand for our product candidates or additional pricing pressures. Further, legislative and regulatory proposals have been made to expand post-approval requirements and restrict sales and promotional activities for pharmaceutical products. We cannot be sure whether additional legislative changes will be enacted, or whether FDA regulations, guidance or interpretations will be changed, or what the impact of such changes on the marketing approvals, if any, of our product candidates, may be. In addition, increased scrutiny by the U.S. Congress of the FDA’s approval process may significantly delay or prevent marketing approval, as well as subject us to more stringent product labeling and post-marketing conditions and other requirements. Individual states in the U.S. have also become increasingly aggressive in passing legislation and implementing regulations designed to control pharmaceutical and biological product pricing, including price or patient reimbursement constraints, affordability review boards, discounts, restrictions on certain product access and marketing cost disclosure and transparency measures, and, in some cases, designed to encourage importation from other countries and bulk purchasing. Legally mandated price controls on payment amounts by third-party payors or other restrictions could harm our business, results of operations, financial condition and prospects. In addition, regional healthcare authorities and individual hospitals are increasingly using bidding procedures to determine what pharmaceutical products and which suppliers will be included in their prescription drug and other healthcare programs. This could reduce the ultimate demand for our products or put pressure on our product pricing, which could negatively affect our business, results of operations, financial condition and prospects. In international markets, reimbursement and healthcare payment systems vary significantly by country (including across the EU’s individual member states), and many countries have instituted price ceilings on specific products and therapies. Future political, economic, and regulatory developments may further affect the ability of pharmaceutical companies to profitably commercialize current and future products.. 63 Table of Contents Environmental Aspects which may Influence the Use of our Material Fixed Assets Our primary research and development activities take place in our facilities in Zwijnaarde, Belgium. For these activities we require, and have obtained, the necessary environmental and biohazard permits from the responsible governments, required by us for the manner in which we use said facilities. New shares issued during 2025 As a result of the exercise of stock options and vesting of RSUs under our Equity Incentive Plan, 1,122,349 new shares were created in 2025. Equity Incentive Plan means the equity incentive plan as adopted by our Board of Directors on December 18, 2014, which was approved by the General Meeting on May 13, 2015, and amended by the General Meeting on April 28, 2016, and November 25, 2019, and the Board of Directors on December 18, 2019, November 5, 2020, December 15, 2021, on February 27, 2023, on February 28, 2024, on 30 June 2025 and on 4 March 2026 The following table shows the developments in our share capital for the year ended December 31, 2025 and on February 19, 2026: Number of shares outstanding on December 31, 2023 59,194,488 Exercise of stock options 1,478,225 Vesting of RSUs 88,244 Number of shares outstanding on December 31, 2024 60,760,957 Exercise of stock options 986,507 Vesting of RSUs 135,842 Number of shares outstanding on December 31, 2025 61,883,306 Exercise of stock options 179,582 Number of shares outstanding on February 19, 2026 62,062,888 64 Table of Contents C.ORGANIZATIONAL STRUCTURE As of December 31, 2025, argenx SE has one subsidiary, argenx BV, which is based in Belgium, and argenx BV has sixteen subsidiaries. The following table sets out the following information for each of our principal subsidiaries: the country of incorporation, and percentage ownership and voting interest held by us (directly or indirectly through subsidiaries). As per December 31, 2025 Name Country Participation argenx SE the Netherlands 100% argenx B.V. Belgium 100% argenx Benelux B.V. Belgium 100% argenx US, Inc. USA 100% argenx Australia Pty. Ltd. Australia 100% argenx Austria Services GmbH Austria 100% argenx Brasil Produtos Farmacêuticos Ltda Brazil 100% argenx Canada Inc. Canada 100% argenx France SAS France 100% argenx Germany GmbH Germany 100% argenx Italy S.r.l. Italy 100% argenx Japan KK. Japan 100% argenx Netherlands Services B.V. the Netherlands 100% argenx Spain S.L. Spain 100% argenx Spain S.L. - Sucursal em Portugal Portugal 100% argenx Switzerland, S.A. Switzerland 100% argenx UK Ltd. United Kingdom 100% Broteio Pharma B.V. the Netherlands 100% The following chart provides an overview of the Group as of the date of this Annual Report. Percentages refer to both the share of capital and voting rights. 65 Table of Contents D.PROPERTY, PLANTS AND EQUIPMENT Our principal executive, operational offices and laboratory space are located in Zwijnaarde, Belgium. In 2024, we added new office space in Zwijnaarde. The total future cash flows related to these leases are represented below in “Note 20 — Leases” in our consolidated financial statements which are included to our Annual Report for the period ended December 31, 2025. We also lease office space in Amsterdam (the Netherlands), Boston (U.S.), Tokyo (Japan), Geneva (Switzerland), Munich (Germany), Issy-Les-Moulineaux (France), Vaughan, Ontario (Canada), Gerrards Cross (UK), Milan (Italy), Madrid (Spain) and Sydney (Australia). In addition, our lease liabilities include a lease plan for company cars with maturity dates up to four years. For a discussion of contractual obligations, please see “Note 27 — Commitments” in our consolidated financial statements which are included to our Annual Report for the period ended December 31, 2025. We have our principal executive, operational offices and laboratory space located in Zwijnaarde, Belgium. The following table sets forth our key leased facilities worldwide as of December 31, 2025: Facility location Use Approx. size (m2) Lease expiry Zwijnaarde, Belgium (leased) Operations and Laboratory Space 5,339 September 30, 2031 Zwijnaarde, Belgium (leased) Office Space 3,765 September 30, 2036 Boston, Massachusetts (leased) Office Space 2,379 August 31, 2030 Tokyo, Japan (leased) Office Space 546 January 17, 2027 Environment, Health and Safety Our primary research and development activities take place in our facilities in Zwijnaarde, Belgium. For these activities we require, and have obtained, the necessary environmental and biohazard permits from the responsible governments, required by us for the manner in which we use said facilities. See “Item 3.D. — Risk Factors”. ITEM 4.A.UNRESOLVED STAFF COMMENTS Not applicable. 66 Table of Contents

The following “Operating and Financial Review and Prospects” should be read together with the information in our financial statements and related notes included elsewhere in this Annual Report. The following discussion is based on our financial information prepared in accordance with the IFRS Accounting Standards (IFRS) as issued by the International Accounting Standards Board (IASB), which may differ in material respects from generally accepted accounting principles in other jurisdictions, including U.S. GAAP. The following discussion includes forward-looking statements that involve risks, uncertainties and assumptions. Our actual results may differ materially from those anticipated in these forward-looking statements as a result of many factors, including but not limited to those described in “Item 3.D. — Risk Factors” and elsewhere in this Annual Report. Please also see “Cautionary Statement Regarding Forward-Looking Statements in this Annual Report. A.OPERATING RESULTS The review of the financial condition and results of operations of certain items from the year ended December 31, 2023, and year-to-year comparisons between the years ended December 31, 2024 and December 31, 2023 that are not included in this Annual Report can be found in “Item 5 — Operating and Financial Review and Prospects” of our annual report on Form 20-F for the year ended December 31, 2024. Overview 2025 was a transformative year for argenx as we advanced our mission to deliver innovation to patients. Our commercial execution reached new heights with the successful expansion of VYVGART, the first-in-class FcRn blocker, which now offers three administration options, including self-injection with the PFS. The PFS launch began in the U.S. in April of this year, followed by the EU and Japan. This evolution reflects our commitment to innovating the patient experience in our two blockbuster indications and pursuing the broadest label for our medicines. The commercialization of the VYVGART franchise generated global product net sales of $4.2 billion in 2025 as compared to $2.2 billion in 2024. Beyond commercial achievements, we continued to execute on a pipeline with breadth and depth, reinforcing our leadership in immunology. We announced positive topline results from the ADAPT SERON clinical trial of VYVGART in Seronegative gMG, further expanding the potential reach of VYVGART. In December of this year, we filed the Seronegative gMG supplemental BLA in pursuit of the broadest MG label of any biologic. In January 2026, the FDA has accepted for priority review a supplemental BLA for VYVGART for the treatment of adults with Seronegative gMG. The application has been granted an expected PDUFA date of May 10, 2026. Additionally, we showcased innovation through our R&D webinar highlighting adimanebart (ARGX-119), a first-in- class agonistic antibody targeting and MuSK to promote maturation and stabilization of the neuromuscular junction, with advancement inCMS. These programs underscore our strategy of entrepreneurial clinical development and commitment to addressing unmet needs across a spectrum of autoimmune and neuromuscular diseases. Looking ahead, in 2026 our teams will strive to continue delivering VYVGART to as many patients as possible. We also expect results to be delivered on four registrational readouts in 2026 and two more in 2027: •Topline results expected in the first quarter of 2026 for Ocular MG (ADAPT OCULUS) with efgartigimod •Topline results expected in the third quarter of 2026 from ALKIVIA clinical trial evaluating three myositis subsetsIMNM,ASyS and DM with efgartigimod •Topline results expected in the fourth quarter of 2026 for EMPASSION clinical trial (MMN) with empasiprubart •Topline results expected in the fourth quarter of 2026 for primary ITP (ADVANCE-NEXT) with efgartigimod •Topline results from UNITY clinical trial (SjD) expected in second half of 2027 with efgartigimod •Topline results from EMVIGORATE clinical trial for empasiprubart (CIDP) expected in second half of 2027 Our Vision 2030 sets the goal to have five new molecules in Phase 3, ten labeled indications, and 50,000 patients on treatment by 2030. It provides a clear roadmap for scaling impact on patients, physicians, and the innovation ecosystem we’re shaping. Achieving this vision will be driven by our core competencies: building winning molecules, entrepreneurial clinical development, and delivering a differentiated patient experience. We plan to continue to prioritize innovation, expand global access, and leverage partnerships to accelerate growth. 67 Table of Contents On our research and development, we continue towards advancing a deep pipeline of both clinical and preclinical-stage product candidates for the treatment of severe autoimmune diseases. Leveraging our technology suite, our ecosystem of partnerships and clinical expertise, we have advanced several candidates into late-stage clinical development, and we currently have multiple programs in the discovery stage. argenx continues to target one Investigational New Drug (IND) application per year in generating a world-class pipeline. We enter the next phase of our ambitious innovation agenda with a solid balance sheet, providing financial strength and flexibility to invest confidently in our pipeline and global expansion. As of December 31, 2025 and December 31, 2024, we had cash and cash equivalents amounting to $3.5 billion and $1.5 billion, respectively; in addition to current financial assets of $0.9 billion and $1.9 billion, respectively. As outlined in our consolidated financial statements which are included to our Annual Report, total assets of $8.7 billion as of the year ended December 31, 2025, compared to $6.2 billion as of the year ended December 31, 2024. The main reason for the material change in balance sheet total is the operational growth of the Company in the period. For the year ended December 31, 2025 the Company recorded a second year of profitability with $1.3 billion compared to our first annual profit for the year ended December 31, 2024 in the amount of $0.8 billion. This was the Company’s first year of operational profitability. As of December 31, 2025, we had accumulated losses of $0.3 billion. We expect our expenses to continue to increase as we continue to execute registrational and proof-of-concept studies across efgartigimod, empasiprubart and adimanebart, as well as the continued investment in our IIP. We anticipate that our expenses will increase if and as we execute on our research and development activities, pre-commercial and commercial activities and various other activities. We are actively engaged in the maintenance, expansion and protection of our intellectual property portfolio, including litigation costs associated with defending against alleged patent infringement claims or enforcing our IP rights against third parties. We expect that the costs of development and commercialization might also increase due to current and future collaborations with research and development partners as well as commercial partners. Information pertaining to the year ended December 31, 2024 was included in our annual report on Form 20-F for the year ended December 31, 2024 under “Item 5 — Operating and Financial Review and Prospects’’ which was filed with the SEC on March 20, 2025. Basis of presentation ‘‘Section 5 Operating and Financial Review and Prospects’’ should be read in parallel to our consolidated financial statements and ‘‘Item 3.D Risk factors’’ which are included to our Annual Report for the period ended December 31, 2025. We specifically, but not exhaustively, indicate the following references to the notes of the financial statements ‘‘Note 2 — Material Accounting Policy Information’’: •the basis of presentation, •the material accounting policies, and •the description of the composition of material accounts, which is further detailed in the notes to the consolidated financial statements. 68 Table of Contents Results of Operations Comparison of Years Ended December 31, 2025 and 2024 Year Ended December 31, (in thousands of $ except for shares and EPS) 2025 2024 % Change Product net sales $ 4,151,316 $ 2,185,883 90% Other operating income1) 96,734 66,156 46% Total operating income 4,248,050 2,252,039 89% Cost of sales (450,665) (227,289) 98% Research and development expenses (1,364,132) (983,423) 39% Selling, general and administrative expenses (1,367,057) (1,055,337) 30% Loss from investment in a joint venture (12,390) (7,644) 62% Total operating expenses (3,194,244) (2,273,693) 40% Operating profit/(loss) $ 1,053,806 $ (21,654) Financial income 163,091 157,509 4% Financial expense (4,082) (2,464) 66% Exchange gains/(losses) 65,792 (48,211) (236)% Profit for the year before taxes $ 1,278,607 $ 85,180 Income tax benefit $ 13,428 $ 747,860 (98)% Profit for the year $ 1,292,035 $ 833,040 55% Weighted average number of shares used for basic profit per share 61,295,149 59,855,585 Basic profit per share (in $) 21.08 13.92 51% Weighted average number of shares used for diluted profit per share 66,029,215 65,177,815 Diluted profit/(loss) per share (in $) 19.57 12.78 53% 1)Comparative figures have been aligned with the presentation adopted in the current period, reflecting the combination of collaboration revenue and other operating income. Product Net Sales Product net sales increased by $2.0 billion to $4.2 billion for the year ended December 31, 2025, compared to $2.2 billion for the year ended December 31, 2024. Our product net sales have increased in the U.S. and other countries as the Company continues to execute on the global commercialization of VYVGART and obtain further approvals worldwide. Revenue by country arising from the commercial sale of VYVGART is presented under ‘‘Note 16 — Segment Reporting’’ in our consolidated financial statements which are appended to our Annual Report for the period ended December 31, 2025. Other Operating Income Other operating income increased by $31 million to $97 million for the year ended December 31, 2025, compared to $66 million for the year ended December 31, 2024. The other operating income recognized in the year ended December 31, 2025 was mainly the result of research and development tax incentives, payroll tax rebates and the clinical supply of product on product net sales of VYVGART in Greater China through Zai Lab. Other operating income is presented under ‘‘Note 15 — Other Operating Income’’ in our consolidated financial statements which are appended to our Annual Report for the period ended December 31, 2025. 69 Table of Contents Research and Development Expenses Research and development expenses consist principally of: •external research and development expenses related to (i) chemistry, manufacturing and control costs for our product candidates, both for preclinical and clinical testing, all of which is conducted by specialized contract manufacturers, (ii) fees and other costs paid to CROs in connection with preclinical testing and the performance of clinical trials for our product candidates, (iii) costs associated with regulatory submissions and approvals, QA and pharmacovigilance and (iv) costs associated with post-approval clinical trials; •personnel expenses related to compensation of research and development staff and related expenses, including salaries, benefits and share‑based payment expenses; and •other expenses. Our research and development expenses totaled $1.4 billion and $1.0 billion for the years ended December 31, 2025 and 2024, respectively. The increase of $0.4 billion in 2025 as compared to 2024 is primarily driven by an increase in personnel expenses and external research and development expenses. Our external research and development expenses for the year ended December 31, 2025 totaled to $0.4 billion, compared to $0.3 billion for the year ended December 31, 2024. The expenses reflect clinical trial costs and manufacturing expenses related to the development of our product candidate portfolio. Personnel expenses relate to internal and external R&D personnel. The expenses also include share-based compensation expenses related to our research and development employees. Our research and development expenses may vary substantially from period to period based on the timing of our research and development activities, including the timing of the initiation of clinical trials, material used in R&D phase and enrollment of patients in clinical trials. Research and development expenses are expected to increase as we advance the clinical development of efgartigimod, empasiprubart, adimanebart and further advance the research and development of our other early-stage pipeline candidates. The successful development of our product candidates is highly uncertain. At this time, we cannot reasonably estimate the nature, timing and estimated costs of the efforts that will be necessary to complete the development of, or the period, if any, in which material net cash inflows may commence from any of our product candidates. This is due to numerous risks and uncertainties associated with developing drugs, as further described in “Item 3.D. - Risk Factors”. Research and development expenses are presented under ‘‘Note 17 — Research and Development Expenses’’ in our consolidated financial statements which are included to our Annual Report for the period ended December 31, 2025. Selling, General and Administrative Expenses Selling, general and administrative expenses consist primarily of: •personnel expenses related to commercial and enabling functions, as well as their related expenses, including salaries, benefits and share‑based payment expenses; •marketing and promotional activities related to the global commercialization of VYVGART; •professional fees related to commercial and enabling functions; •Board of Directors expenses consisting of directors’ fees, travel expenses and share-based compensation for non- executive directors; and •other expenses. Our selling, general and administrative expenses totaled $1.4 billion and $1.1 billion for the years ended December 31, 2025 and 2024, respectively. The increase of $0.3 billion for the year ended December 31, 2025 principally resulted from: •increased professional and marketing fees, including promotional and marketing costs primarily due to the scaling of our commercial operations relating to VYVGART; 70 Table of Contents •increased costs of personnel expenses, related to planned increase in the headcount of our Selling, general and administrative employees recruited to strengthen our enabling functions and the scaling of our commercial operations relating to VYVGART; and •continued investment in our Digital Technology infrastructure. Selling, general and administrative expenses are presented under ‘Note 18 Selling, General and Administrative Expenses’’ in our consolidated financial statements which are included to our Annual Report for the period ended December 31, 2025. Financial Income and (Expense) For the year ended December 31, 2025, financial income amounted to $163 million compared to $158 million for the year ended December 31, 2024. The increase of $6 million in 2025 related primarily to the capital increase of our cash, cash equivalents, and current financial assets. B.LIQUIDITY AND CAPITAL RESOURCES Sources of Funds Our capitalization is detailed in the “Consolidated Statements of Financial Position” which are included to our Annual Report for the period ended December 31, 2025. As of December 31, 2025 on an actual basis, the Company had a total equity amount of $7.3 billion. Since our inception in 2008, we have invested most of our resources in developing our product candidates, building our intellectual property portfolio, developing our supply chain, conducting business planning, raising capital and providing general and administrative support for these operations. December 31, 2024To date, we have funded our operations through (i) public and private placements of equity securities, (ii) upfront, milestone and expense reimbursement payments received from our collaborators, (iii) funding from governmental bodies, (iv) proceeds from exercise of employee stock options and (v) interest income from the investment of our cash and cash equivalents, in addition to current financial assets. Through December 31, 2025, we have raised gross proceeds of $5.9 billion from private and public offerings of equity securities. Our commercial operations have also started to contribute to the funding of our operations based on positive cash flow from operating activities as of the year ended December 31, 2025. As we continue to invest in innovation, our cash flows may fluctuate, are difficult to forecast and will depend on many factors. We have no ongoing material financing commitments, such as lines of credit or guarantees, that are expected to affect our liquidity over the next five years, other than leases and commitments as part of our operations, which are detailed in “Note 27 — Commitments” and “Note 24 — Financial Risk Management” in our consolidated financial statements which are included to our Annual Report for the period ended December 31, 2025. For more information as to the risks associated with our future funding needs, see “Item 3.D. — Risk Factors — Risk Factors Related to argenx’s Financial Position and Need for Additional Capital”. For more information as to our financial instruments, please see “Note 24 — Financial Risk Management” in our consolidated financial statements which are included to our Annual Report for the period ended December 31, 2025. 71 Table of Contents Cash Flows Comparison for the Years Ended December 31, 2025 and 2024 As of December 31, 2025, the Company had $3.5 billion of cash and cash equivalents compared to $1.5 billion as of December 31, 2024. The Company’s cash and cash equivalents increased by $2.0 billion year-over- year mainly resulting from positive cash flow from operating activities and a higher amount of capital held in cash and cash equivalents as opposed to current financial assets. The Company’s net cash flow from operating activities increased by $0.8 billion for the year ended December 31, 2025 compared to the year ended December 31, 2024 mainly due to increased product net sales of VYVGART partially offset by buildup of working capital. Net cash flow used in investing activities increased by $1.7 billion for the year ended December 31, 2025 compared to the year ended December 31, 2024 mainly due to the nature of financial instruments held as of the reporting date classified as cash and cash equivalents coming from capital held in the year as current financial assets. This is partially offset by payments related to regulatory and sales based milestones to Halozyme. Net cash flow from financing activities decreased by $47 million for the year ended December 31, 2025 compared to the year ended December 31, 2024 mainly due to proceeds from the exercise of stock options. For more information, please see “Consolidated Statements of Cash Flows” and “Note 11 Cash and Cash Equivalents” in our consolidated financial statements which are included to our Annual Report for the period ended December 31, 2025. Operating and Capital Expenditure Requirements We recorded a profit of $1.3 billion for the year ended December 31, 2025. Our operating expenditures are detailed above in our research and development expenses along with our Selling, general and administrative expenses. We anticipate that our operating expenses will increase as we intend to continue conducting research and development, as well as continuing our efforts to expand our sales & marketing and establish our distribution infrastructure. Although we have generated product net sales of $4.2 billion from global product net sales of VYVGART for the year ended December 31, 2025, which supports our current profitability, we cannot provide assurances that we will be profitable or able to sustain net profitability in the future based on these indications alone. Furthermore, we cannot provide any assurances that we will receive the regulatory approvals to commercialize VYVGART in other indications or in other countries. On the basis of current assumptions, we expect that our existing cash and cash equivalents and current financial assets will enable us to fund our operating expenses and capital expenditure requirements through at least the next twelve months. The adequacy of our available funds to meet our future operating expenses and capital expenditures will depend on numerous risks and uncertainties associated with the development and commercialization of efgartigimod and our other product candidates and discovery stage programs and because the extent to which we may enter into collaborations with third parties for the development of these product candidates is unknown. We are unable to estimate the amounts of increased capital outlays and operating expenses associated with completing the research and development of our product candidates. Our future capital requirements for efgartigimod, empasiprubart, adimanebart, our other product candidates and discovery stage programs will depend on many factors, including: •the progress, timing and completion of preclinical testing and clinical trials for our current or any future product candidates; •the number of potential new product candidates we identify and decide to develop; •the time and costs involved in obtaining regulatory approvals for our product candidates and any delays we may encounter as a result of evolving regulatory requirements or adverse results with respect to any of our product candidates; •selling and marketing activities undertaken in connection with the commercialization of VYVGART or potential commercialization of any of our current or any future product candidates, if approved, and costs involved in the creation of an effective sales and marketing organization; 72 Table of Contents •manufacturing activities undertaken for VYVGART and potential commercialization of any of our current or any future product candidates, if approved, and costs involved in the creation of an effective supply chain; •the costs involved in growing our organization to the size needed to allow for the research, development and potential commercialization of our current or any future product candidates; •the costs involved in filing patent applications and maintaining and enforcing patents or defending against claims or infringements raised by third parties; •the maintenance of our existing collaboration agreements, the entry into new collaboration agreements and the pursuit of other strategic business development opportunities; and •developments related to global economic uncertainties and political instability. For more information as to the risks associated with our future funding needs, see “Item 3.D. — Risk Factors — Risk Factors — Risk Factors Related to argenx’s Financial Position". Working capital statement In our opinion, the working capital of the Company is sufficient for the Company’s present requirements, at least for a period of 12 months from the date of this Annual Report. Cash Investment Policy The Company has adopted a policy whereby cash and cash equivalents and current financial assets are invested with several highly reputable banks and financial institutions. The main purpose of the Cash Investment Policy is to preserve the available cash and to ensure sufficient short-term liquidity at all times. Therefore, the Company holds its cash, cash equivalents and current financial assets mainly with banks which are independently rated A- or higher. Amounts of cash held with banks rated lower than A- are limited to insignificant balances. The maximum amount and tenor of time deposits depends on the rating of the counterparty bank. The Company also holds cash equivalents in the form of money market funds with a low historical volatility. These money market funds are highly liquid investments and can be readily convertible into a known amount of cash. The Company has adopted a policy whereby money market funds must have a minimum rating of A of which 95% should have a AAA-rating. For more information as to our treasury policy and liquidity, please see “Note 24 — Financial Risk Management” in our consolidated financial statements which are included to our Annual Report for the period ended December 31, 2025. Off-Balance Sheet Arrangements During the periods presented we did not have, and we do not currently have, any off‑balance sheet arrangements, as defined in the applicable rules and regulations, such as relationships with unconsolidated entities or financial partnerships, which are often referred to as structured finance or special purpose entities, established for the purpose of facilitating financing transactions that are not required to be reflected on our balance sheets. Our scope of consolidated entities is disclosed in “Note 29 — Overview of Consolidation Scope” in our consolidated financial statements which are included to our Annual Report for the period ended December 31, 2025. C.RESEARCH AND DEVELOPMENT, PATENTS AND LICENSES For a discussion of our research and development policies, refer to the “Item 4 — Information on the Company” and “Item 5 — Operating and Financial Review and Prospects”. D.TREND INFORMATION Other than as disclosed elsewhere in this Annual Report, we are not aware of any trends, uncertainties, demands, commitments or events for the current financial period that are reasonably likely to have a material effect on our net revenues, income, profitability, liquidity, capital resources or prospects, or that caused the disclosed financial information to be not necessarily indicative of future operating results or financial conditions. There has been no significant change in the financial performance or the financial position of the Group since the balance sheet date of December 31, 2025. 73 Table of Contents For more information, please refer to “Item 4.B — Business Overview”, “Item 5.A. — Operating Results”, “Item 5.B. — Liquidity and Capital Resources” and “Note 27 — Commitments’’ in our consolidated financial statements which are appended to our Annual Report for the period ended December 31, 2025. E.CRITICAL ACCOUNTING ESTIMATES See “Note 3 — Critical accounting judgments and major sources of estimation uncertainty’’ in our consolidated financial statements which are appended to our Annual Report for the period ended December 31, 2025.