You should read the following discussion and analysis of financial condition and operating results together with our interim unaudited condensed consolidated financial statements and the related notes and other financial information included elsewhere in this Quarterly Report on Form 10-Q, as well as our audited consolidated financial statements and the related notes included in our Annual Report on Form 10-K for the year ended December 31, 2025. Some of the information contained in this discussion and analysis or set forth elsewhere in this Quarterly Report on Form 10-Q contains forward-looking statements based upon current plans, expectations and beliefs involving significant risks and uncertainties. As a result of many important factors, including those set forth under “Risk Factors” and elsewhere in this Quarterly Report on Form 10-Q, our actual results may differ materially from those anticipated in these forward-looking statements. For convenience of presentation some of the numbers have been rounded in the text below. Overview We are a clinical-stage biopharmaceutical company developing azenosertib (ZN-c3), an investigational, potentially first-in-class and best-in-class WEE1 inhibitor, for patients with ovarian cancer and other tumor types. In clinical trials, azenosertib has been well tolerated and has demonstrated anti-tumor activity as a single agent across multiple tumor types. We are currently focused on advancing the clinical development of azenosertib in Cyclin E1-positive platinum-resistant ovarian cancer, or PROC. We believe that our DENALI (ZN-c3-005) Part 2 clinical trial of azenosertib in patients with Cyclin E1-positive PROC, if successful, has the potential to support an accelerated approval, subject to U.S. Food and Drug Administration, or FDA, review. Our Phase 3 ASPENOVA (ZN-c3-020) clinical trial is designed as a confirmatory trial to support conversion to potential full approval, subject to data outcomes. We also believe that azenosertib has broad franchise potential beyond Cyclin E1-positive PROC. We exclusively in-license or solely own worldwide development and commercialization rights to azenosertib. Azenosertib (WEE1 Inhibitor) Mechanism of Action Azenosertib is an investigational, potentially first-in-class and best-in-class oral, small molecule WEE1 inhibitor. The inhibition of WEE1, a DNA damage response kinase, drives cancer cells into mitosis without being able to repair damaged DNA, resulting in cell death and thereby preventing tumor growth and potentially causing tumor regression. We have designed azenosertib to have advantages over other investigational therapies targeting WEE1, including superior selectivity and pharmacokinetic, or PK, properties. Cyclin E1 Expression as a Sensitive and Specific Predictive Biomarker in PROC Cells with Cyclin E1 activation are exquisitely sensitive to WEE1 inhibition via azenosertib because Cyclin E1 activation further accelerates cancer cells into the DNA replication phase without adequate DNA repair. As a result, we have used retrospective analyses to establish Cyclin E1 as a sensitive and specific predictive biomarker that can be used to identify patients who might benefit from azenosertib. Based on published retrospective analyses, Cyclin E1 alteration is a biomarker of poor prognosis and low benefit from standard-of-care single-agent chemotherapy in PROC patients. Additionally, real-world data from two independent cohorts (Tempus Lens Ovarian cancer dataset and our historical clinical studies) presented at the 2026 American Association for Cancer Research, or AACR, annual meeting, consistently demonstrated that Cyclin E1-positive ovarian cancer patients experience worse clinical outcomes. We are working with a diagnostic partner to validate a companion diagnostic test that will identify patients with PROC that overexpress the Cyclin E1 protein using our proprietary immunohistochemistry, or IHC, cutoff. A prototype of this test is being used in DENALI Part 2 and our Phase 3 ASPENOVA clinical trial. 25 Market Opportunity In 2022, the global ovarian cancer market was approximately $3 billion, with significant growth expected over the next several years. PROC is a subset of the ovarian cancer market. Based on our retrospective, historical analysis utilizing our IHC cutoff, we estimate that approximately 50% of PROC patients overexpress Cyclin E1 protein, which accounts for approximately 20,000 patients on an annual basis in the United States, EU4 (France, Germany, Italy, Spain), the United Kingdom and Japan, based on 2025 estimates. As a result, we believe there is a significant opportunity for azenosertib in Cyclin E1-positive PROC patients. Moreover, the successful launch of mirvetuximab in PROC patients with high folate receptor alpha, or FRα-high, expression underscores the demand for biomarker-directed therapies for PROC patients. The overlap between FRα-high PROC patients and those that have Cyclin E1 overexpression is estimated to be less than 20% of all PROC patients, which highlights the significant unmet need in patients with Cyclin E1-positive PROC. We believe there is additional market opportunity for azenosertib in earlier lines of treatment for ovarian cancer, and across other solid tumor types. Clinical Development Program The following ongoing and planned studies constitute the current clinical development program for azenosertib: •Monotherapy – Phase 2 Clinical Trial in PROC (DENALI - ZN-c3-005) ◦DENALI Part 1b is a fully enrolled single-arm study that evaluated azenosertib monotherapy at 400 mg QD 5:2 (single daily dose on an intermittent schedule of five days on and two days off), in 102 patients with PROC. Tissue collection for biomarker assessment was mandated in the study and upon a retrospective analysis, approximately 50% of the patients were Cyclin E1-positive per our IHC cutoff. In 2025, we announced clinical data from this study. ▪DENALI Part 2 is prospectively enrolling PROC patients with Cyclin E1 protein overexpression based on our proprietary IHC cutoff. Part 2 consists of three cohorts across a seamless design that may support accelerated approval in patients with Cyclin E1-positive PROC, pending positive study outcomes and further discussions with the FDA. The study design consists of the following parts: ◦Part 2a: Dose confirmation in patients with 1-3 prior lines of therapy, or up to 4 prior lines allowed in prior mirvetuximab treatment in patients with high FRα. Two doses were evaluated, 300mg QD 5:2 and 400mg QD 5:2, with approximately 30 patients enrolled per dose group. In April 2026, we announced that 400mg QD 5:2 was selected as the pivotal monotherapy dose and that recruitment at the 300mg QD 5:2 dose level has been discontinued. All patients enrolled in Part 2a will contribute to the overall safety database submitted to the FDA. ◦Part 2b: Enrollment expansion in the same patient population as Part 2a at the selected 400mg QD 5:2 dose up to approximately 100 patients, including patients at that dose in Part 2a. Enrollment in this cohort is complete. ◦Part 2c: Broadening study population, which is expected to include approximately 40 patients previously treated with a taxane-containing regimen for PROC, with 1-4 prior lines of therapy allowed, including prior mirvetuximab in patients with high FRα. This cohort is currently enrolling. 26 In July 2026, we met with the FDA in a Type D meeting to align on key points related to our accelerated approval strategy, including dose. The FDA had no objection to the continued study of the selected monotherapy dose of azenosertib at 400mg QD 5:2 in patients with Cyclin E1-positive PROC, selected based on a pre-specified interim analysis from DENALI Part 2a. The FDA acknowledged the DENALI Part 2 study population, including the 2c cohort, has the potential to support an accelerated approval pathway, subject to the strength of the data and the landscape of approved agents at the time of regulatory action. The FDA has granted Fast Track Designation to azenosertib for the treatment of patients with Cyclin E1-positive PROC. The integrated dataset of DENALI Parts 2a, 2b, and 2c is designed to support accelerated approval in the Cyclin E1 biomarker-selected patient population, subject to regulatory review. We expect to provide a topline readout of DENALI Part 2 in the first half of 2027 to allow for data maturation post full enrollment. •Monotherapy – Phase 3 Clinical Trial in Cyclin E1-positive PROC (ASPENOVA – ZN-c3-020) ASPENOVA is a Phase 3 randomized, confirmatory clinical trial designed to support full approval of azenosertib in patients with Cyclin E1-positive PROC. The trial is expected to enroll approximately 420 patients and compare azenosertib monotherapy at 400mg QD 5:2 to the investigator's choice of standard-of-care single-agent chemotherapy (paclitaxel, pegylated liposomal doxorubicin, gemcitabine, or topotecan). The trial design was based on feedback from the U.S. FDA regarding requirements for seeking approval under the accelerated approval pathway and requirements to support potential conversion to full approval, subject to data outcomes. In May 2026, we announced that the first patient had been dosed in the ASPENOVA trial. •Combination – Phase 1b Clinical Trial of Azenosertib and Chemotherapy or Bevacizumab in Ovarian Cancer (MUIR - ZN-c3-002) MUIR is a multi-part, open-label Phase 1b clinical trial evaluating the safety, efficacy and preliminary clinical activity of azenosertib in combination in patients with ovarian cancer. The study design consists of the following parts: ▪Part 1: Enrolled patients with PROC treated with azenosertib in combination with one of four chemotherapy regimens: carboplatin, gemcitabine, pegylated liposomal doxorubicin, or paclitaxel. Primary objectives were safety and tolerability, with key secondary objectives including clinical activity assessed by objective response rate, duration of response, and progression-free survival per RECIST v1.1. In May 2026, we announced data from MUIR Part 1 focusing on azenosertib in combination with paclitaxel in PROC as paclitaxel is commonly used across multiple tumor types, including ovarian cancer. These data are described in the next section below titled “Recent Data and Presentations.” Data from the other combination arms will be presented at a later date. ▪Part 2: Evaluating azenosertib in combination with bevacizumab as a maintenance regimen (in the first line, or 1L, or second line, or 2L, of treatment) in patients with advanced ovarian, peritoneal, or fallopian tube cancer following platinum-based chemotherapy. The dose escalation portion will determine the recommended dose for azenosertib orally once daily 5 days on, 2 days off in 21-day cycles in combination with bevacizumab 15mg/kg intravenously on Day 1 of each 21-day cycle. The dose expansion portion will evaluate azenosertib at the recommended dose determined from the dose escalation portion in combination with bevacizumab. The dose expansion portion is expected to enroll approximately 40 patients with platinum-sensitive ovarian cancer in 2L who progressed while on a PARP inhibitor for 1L maintenance. The primary objective is safety and tolerability; secondary objectives include preliminary clinical activity of the combination as assessed by progression-free survival for the dose expansion portion. The dose expansion portion is currently enrolling. 27 Recent Data and Presentations In April 2026 at the AACR Annual Meeting, we presented a poster with preclinical data showing encouraging activity and tolerability of azenosertib combinations in treatment-naïve and ADC-resistant triple negative breast cancer, or TNBC, supporting the potential for pipeline expansion beyond ovarian cancer. At this meeting, we also presented a poster with real-world data demonstrating that Cyclin E1-positive ovarian cancer patients have significantly worse outcomes, independent of CCNE1 gene amplification status, reinforcing the potential for azenosertib to address the unmet need for these patients. In May 2026, we presented data from Part 1 of the Phase 1b MUIR trial at the ASCO Annual Meeting. The findings reflect a December 1, 2025 data cutoff and include 46 patients who received azenosertib across four dose cohorts — 200 mg QD continuously or 200 mg, 250 mg, or 300 mg QD intermittently (5 days on, 2 days off) — in combination with paclitaxel 80 mg/m². All patients had received prior paclitaxel. The data showed combinability and activity of azenosertib in an all-comer PROC setting, demonstrating the potential for azenosertib in multiple lines of ovarian cancer and more broadly in combination with cytotoxic agents in other tumor types. For a summary of the data we presented at the ASCO Annual Meeting, please refer to the 8-K Current Report we filed with the SEC on May 21, 2026. Liquidity Overview Since our inception, our operations have been limited to organizing and staffing our company, business planning, raising capital, establishing our intellectual property portfolio and performing research and development of our product pipeline. We do not have any products approved for commercial sale and have not generated any revenues from product sales. We will not generate revenue from product sales unless and until we successfully complete clinical development, obtain regulatory approval for, and commercialize one or more of our product candidates. We will need to raise substantial additional capital to support our continuing operations and pursue our growth strategy. Since inception, we have incurred significant operating losses. Our net losses were $137.1 million for the year ended December 31, 2025. We had net losses of $77.6 million and $75.2 million for the six months ended June 30, 2026 and June 30, 2025, respectively. We had an accumulated deficit of $1.3 billion as of June 30, 2026. We expect to continue to incur significant expenses and operating losses for the foreseeable future. We had cash, cash equivalents and marketable securities of $174.6 million as of June 30, 2026. We believe that our existing cash, cash equivalents and marketable securities as of June 30, 2026 will be sufficient to fund our operating expenses and capital expenditure requirements into late 2027. We have based these estimates on assumptions that may prove to be imprecise, and we could utilize our available capital resources sooner than we expect. 28 License Agreements and Strategic Collaborations Recurium IP Holdings, LLC License Agreement In December 2014, our wholly owned subsidiary, Zeno Pharmaceuticals, Inc., entered into the Recurium Agreement, with Recurium IP Holdings, LLC, or Recurium IP, which was subsequently amended, under which Zeno Pharmaceuticals, Inc. was granted an exclusive worldwide license to certain intellectual property rights owned or controlled by Recurium IP to develop and commercialize pharmaceutical products for the treatment or prevention of disease, other than for providing pain relief. Following a corporate restructuring, our wholly owned subsidiary, Zeno Management, Inc., or ZMI, became the Zentalis contracting party to the Recurium Agreement. The intellectual property rights exclusively licensed by ZMI under the Recurium Agreement include certain intellectual property covering azenosertib. ZMI has the right to sublicense its rights under the Recurium Agreement, subject to certain conditions. ZMI is required to use commercially reasonable efforts to develop and commercialize at least one product that comprises or contains a compound modulating one of ten specific biological targets and to execute certain development activities. Under the terms of the Recurium Agreement, ZMI is obligated to make development and regulatory milestone payments, pay royalties on net sales, and make certain sublicensing payments with respect to products that comprise or contain a compound modulating one of ten specific biological targets, including azenosertib. ZMI is obligated to make development and regulatory milestone payments for each such licensed product of up to $44.5 million, which covers the first two indications for which such licensed product receives regulatory approval and includes a $7.0 million milestone payment incurred as a result of the commencement of our Phase 3 ASPENOVA clinical trial and paid during the three months ended June 30, 2026. In the event that a licensed product receives regulatory approval in any additional indications beyond the first two, ZMI would be obligated to pay an additional one-time milestone payment for each such approval. In addition, ZMI is obligated to make milestone payments of up to $150,000 for certain licensed products used in animals. ZMI is also obligated to pay royalties on sales of such licensed products at a mid- to high-single digit percentage. In addition, if ZMI chooses to sublicense or assign to any third parties its rights under certain patents exclusively in-licensed under the Recurium Agreement, ZMI must pay to Recurium IP 20% of certain sublicensing income received in connection with such transaction. The Recurium Agreement will expire on the later of December 21, 2032 and, on a country-by-country basis, on the date of expiration of the last-to-expire royalty term for all licensed products in such country, unless earlier terminated by either party for cause or a bankruptcy event. Pfizer Development Agreement In April 2022, we entered into a development agreement with Pfizer to collaborate to advance the clinical development of azenosertib. We did not grant Pfizer any economic ownership or control of azenosertib or the rest of our pipeline. In October 2022, we announced our first clinical development collaboration with Pfizer to initiate a Phase 1/2 dose escalation study of azenosertib, in combination with encorafenib and cetuximab (an FDA-approved standard of care known as the BEACON regimen) in patients with BRAF V600E-mutant mCRC. In January 2025, we announced that we would not advance to the dose expansion phase of the study due to resource prioritization and an evolving treatment landscape. GSK Clinical Trial Collaboration and Supply Agreement In April 2021, we entered into a clinical trial collaboration and supply agreement with GSK under which we have evaluated the combination of azenosertib and niraparib, GSK’s poly (ADP-ribose) polymerase (PARP) inhibitor, in patients with PROC. In January 2025, we announced that the trial was fully enrolled and that we were not proceeding further with the development of the combination of azenosertib with niraparib as efficacious exposures of azenosertib were not reached. Pursuant to this agreement, we were responsible for the conduct and cost of the study, under the supervision of a joint development committee made up of our representatives and representatives of GSK. GSK supplied niraparib for use in the collaboration, at no cost to us. 29 This agreement does not grant any right of first negotiation to participate in future clinical trials, and neither party granted the other any additional right or ability to evaluate their respective compounds in any other clinical studies, either as monotherapy or in combination with any other product or compound, in any therapeutic area. The agreement with GSK will expire upon completion of all obligations of the parties thereunder or upon termination by either party. In addition, there are standard early termination provisions under this agreement. Components of Our Results of Operations Revenue To date, we have not generated any revenue from product sales, and we do not expect to generate any revenue in the foreseeable future. We have generated, and may in the future generate, revenue from payments received under our licensing, collaboration and asset sale agreements, which included payments of upfront fees, license fees, milestone-based payments and reimbursements for research and development efforts. Research and Development Expenses Research and development expenses consist primarily of costs incurred for our research activities, including our discovery efforts, and the development of our product candidates, and include: •salaries, benefits and other related costs, including non-cash stock-based compensation expense, for personnel engaged in research and development functions; •expenses incurred under agreements with third parties, including CROs and other third parties that conduct research, preclinical activities and clinical trials on our behalf as well as CMOs that manufacture drug material for use in our preclinical studies and clinical trials; •costs of outside consultants, including their fees, non-cash stock-based compensation and related travel expenses; •the costs of laboratory supplies and acquiring, developing and manufacturing preclinical study and clinical trial materials; •license payments made for intellectual property used in research and development activities; and •allocated expenses for rent and maintenance of facilities and other operating costs. We expense research and development costs as incurred. Reimbursed research and development costs under certain collaborative arrangements are recorded as a reduction to research and development expenses and are recognized in the period in which the related costs are incurred. We track external development costs by product candidate or development program, but we do not allocate personnel costs, general license payments made under our licensing arrangements or other internal costs to specific development programs or product candidates. These costs are included in unallocated research and development expenses and discontinued programs in the table below. 30 The following table summarizes our research and development expenses by product candidate or development program: Three Months Ended June 30, Six Months Ended June 30, 2026 2025 2026 2025 Azenosertib $ 23,687 $ 10,945 $ 40,227 $ 20,551 Unallocated research and development expenses and discontinued programs 11,476 16,665 23,652 34,306 Total research and development expenses $ 35,163 $ 27,610 $ 63,879 $ 54,857 Research and development activities are central to our business model. Product candidates in later stages of clinical development generally have higher development costs than those in earlier stages of clinical development, primarily due to the increased size and duration of later-stage clinical trials. The successful development of azenosertib, and any of our future product candidates is highly uncertain. At this time, we cannot determine with certainty the duration and costs of our existing and future clinical trials of azenosertib or any other product candidate we may develop or if, when, or to what extent we will generate revenue from the commercialization and sale of any product candidate for which we obtain marketing approval. We may never succeed in obtaining marketing approval for azenosertib, or any future product candidate. The duration, costs and timing of clinical trials and development of our product candidates and any other product candidate we may develop in the future will depend on a variety of factors, including: •per patient trial costs; •the number of patients who enroll in each trial; •the number of trials required for approval; •the number of sites included in the trials; •the countries in which the trials are conducted; •the length of time required to enroll eligible patients; •the drop-out or discontinuation rates of patients; •any delays in clinical trials, including as a result of clinical holds or the global macroeconomic environment; •potential additional safety monitoring requested by regulatory agencies; •the duration of patient participation in the trials and follow-up; •the phase of development of the product candidate; •the efficacy and safety profile of the product candidate; •uncertainties in clinical trial design and patient enrollment rates; •the actual probability of success for our product candidates, including the safety and efficacy, early clinical data, competition, manufacturing capability and commercial viability; 31 •significant and changing government regulation and regulatory guidance; •the timing and receipt of any marketing approvals; •the expense of filing, prosecuting, defending and enforcing any patent claims and other intellectual property rights; and •our ability to attract and retain skilled personnel. A change in the outcome of any of these variables with respect to the development of a product candidate could mean a significant change in the costs and timing associated with the development of that product candidate. For example, if the FDA or another regulatory authority were to require us to conduct clinical trials beyond those that we anticipate will be required for the completion of clinical development of a product candidate, or if we experience significant delays in our clinical trials due to patient enrollment or other reasons, we would be required to expend significant additional financial resources and time on the completion of clinical development. General and Administrative Expenses General and administrative expenses consist primarily of salaries and other related costs, including non-cash stock-based compensation, for personnel in our executive, finance, business development and administrative functions. General and administrative expenses also include legal fees relating to intellectual property and corporate matters; professional fees for accounting, auditing, tax and consulting services; insurance costs; travel expenses; and facility-related expenses, which include direct depreciation costs and allocated expenses for rent and maintenance of facilities and other operating costs. Restructuring Expenses Restructuring expenses consist of involuntary employee termination benefits pursuant to a one-time benefit arrangement. Investment and Other Income (Expense), Net Investment and other income (expense), net consists of interest earned on cash, cash equivalents and available-for-sale marketable securities, sublease income and the change in value of equity securities during the period. Income Taxes Since our inception, we and our corporate subsidiaries have generated cumulative federal, state and foreign net operating loss in certain jurisdictions for which we have not recorded any net tax benefit due to uncertainty around utilizing these tax attributes within their respective carryforward periods. 32 Results of Operations Comparison of Three Months Ended June 30, 2026 to Three Months Ended June 30, 2025 The following table summarizes our results of operations for the periods indicated, together with the changes in those items in dollars: Three Months Ended June 30, Increase (Decrease) 2026 2025 (in thousands) Operating Expenses Research and development $ 35,163 $ 27,610 $ 7,553 General and administrative 9,228 8,448 780 Total operating expenses 44,391 36,058 8,333 Loss from operations (44,391) (36,058) (8,333) Other Income (Expense) Investment and other income, net 2,243 9,184 (6,941) Net loss before income taxes (42,148) (26,874) (15,274) Income tax expense 138 — 138 Net loss $ (42,286) $ (26,874) $ (15,412) 33 Research and Development Expenses Research and development expenses for the three months ended June 30, 2026 were $35.2 million, compared to $27.6 million for the three months ended June 30, 2025. The increase of $7.6 million was primarily due to a $7.0 million milestone payment to Recurium IP Holdings, LLC required as a result of the commencement of our Phase 3 ASPENOVA clinical trial and an increase of $5.2 million related to clinical expenses and drug manufacturing, including costs associated with advancing the DENALI and ASPENOVA trials. This increase was partially offset by a decrease of $4.5 million for personnel expense, of which $2.1 million was non-cash stock-based compensation, and a decrease of $0.1 million related to allocated overhead. General and Administrative Expenses General and administrative expenses for the three months ended June 30, 2026 were $9.2 million, compared to $8.4 million during the three months ended June 30, 2025. This increase of $0.8 million was primarily attributable to an increase of $1.7 million for consulting and outside services. This increase was partially offset by a decrease of $0.9 million for non-cash stock-based compensation. Investment and Other Income, Net Investment and other income (expense), net was $2.2 million for the three months ended June 30, 2026, compared to $9.2 million for the three months ended June 30, 2025. The decrease of $7.0 million was primarily driven by a non-cash recognized gain of $4.6 million on the mark to market adjustment for equity securities during the three months ended June 30, 2025 and a decrease of $1.7 million in returns on invested cash and marketable debt securities. A gain of $0.5 million on fixed assets sold during the three months ended June 30, 2025 and a decrease of $0.2 million in other income and expense accounts also contributed to the overall decrease. Comparison of Six Months Ended June 30, 2026 to Six Months Ended June 30, 2025 The following table summarizes our results of operations for the periods indicated, together with the changes in those items in dollars: Six Months Ended June 30, Increase (Decrease) 2026 2025 (in thousands) Operating Expenses Research and development $ 63,879 $ 54,857 $ 9,022 General and administrative 18,367 19,028 (661) Restructuring — 7,796 (7,796) Total operating expenses 82,246 81,681 565 Loss from operations (82,246) (81,681) (565) Other Income (Expense) Investment and other income, net 4,866 6,528 (1,662) Net loss before income taxes (77,380) (75,153) (2,227) Income tax expense 258 — 258 Net loss $ (77,638) $ (75,153) $ (2,485) Research and Development Expenses Research and development expenses for the six months ended June 30, 2026 were $63.9 million, compared to $54.9 million for the six months ended June 30, 2025. The increase of $9.0 million was primarily due to a $7.0 million 34 milestone payment to Recurium IP Holdings, LLC required as a result of the commencement of our Phase 3 ASPENOVA clinical trial and an increase of $11.5 million related to clinical expenses and drug manufacturing, including costs associated with advancing the DENALI and ASPENOVA trials. These increases were partially offset by a decrease of $8.4 million for personnel expense, of which $3.4 million was non-cash stock-based compensation and a decrease of $1.1 million related to a one time impairment charge recorded during the quarter ended March 31, 2025. General and Administrative Expenses General and administrative expenses for the six months ended June 30, 2026 were $18.4 million, compared to $19.0 million during the six months ended June 30, 2025. This decrease of $0.6 million was attributable to a decrease of $2.8 million of personnel expense of which $2.2 million was non-cash stock-based compensation. This decrease was partially offset by an increase of $2.2 million related primarily to consulting and outside services. Restructuring Expenses On January 22, 2025, our Board of Directors approved a strategic restructuring of the Company to support execution of late-stage development for azenosertib, and extend its cash runway beyond a potentially registration-enabling azenosertib data readout from the Company’s DENALI Part 2 study, anticipated in the first half of 2027. In connection with this strategic restructuring, the Company reduced its workforce by approximately 40%. Restructuring expenses for the six months ended June 30, 2026 were zero, compared to $7.8 million during the six months ended June 30, 2025. Investment and Other Income, Net Investment and other income (expense), net was $4.9 million for the six months ended June 30, 2026, compared to $6.5 million for the six months ended June 30, 2025. The decrease of $1.6 million was primarily driven by a decrease of $3.5 million in returns on invested cash and marketable debt securities partially offset by a non-cash recognized loss of $2.4 million on the mark to market adjustment for equity securities during the six months ended June 30, 2025. A gain of $0.5 million on fixed assets sold during the six months ended June 30, 2025 also contributed to the overall decrease. Liquidity and Capital Resources Since our inception, our operations have been limited to organizing and staffing our company, business planning, raising capital, establishing our intellectual property portfolio and performing research and development of our product pipeline. We do not have any products approved for commercial sale and have not generated any revenues from product sales and we have incurred significant operating losses. As a result, we will need to raise substantial additional capital to support our continuing operations and pursue our strategy. Until such time as we can generate significant revenue from product sales, if ever, we plan to finance our operations through the sale of equity, debt financings or other capital sources, which may include collaborations with other companies or other strategic transactions. There are no assurances that we will be successful in obtaining an adequate level of financing as and when needed to finance our operations on terms acceptable to us or at all, particularly in light of the global macroeconomic environment, including the ongoing trade tensions between the United States and certain ex-U.S. governments, ongoing military conflicts, and fluctuating inflation and interest rates. If we are unable to secure adequate additional funding as and when needed, we may have to significantly delay, scale back or discontinue the development and commercialization of azenosertib or delay our pursuit of potential in-licenses or acquisitions. Because of the numerous risks and uncertainties associated with developing and commercializing therapeutics, we are unable to predict the timing or amount of increased expenses or when or if we will be able to achieve or maintain profitability. Even if we are able to generate revenue from product sales, we may not become profitable. If we fail to 35 become profitable or are unable to sustain profitability on a continuing basis, then we may be unable to continue our operations at planned levels and be forced to reduce or terminate our operations. We do not currently have any approved products and have never generated any revenue from product sales. To date, we have financed our operations primarily through the sale of equity securities. From inception through June 30, 2026, we raised a total of $1.2 billion in gross proceeds from the sale of shares of our common stock and convertible preferred units. As of June 30, 2026, we had $24.8 million in cash and cash equivalents, $149.8 million in marketable debt securities, and an accumulated deficit of $1.3 billion. We maintain the majority of our cash and cash equivalents in accounts with major financial institutions, and our deposits at these institutions exceed insured limits. Market conditions can impact the viability of these institutions. In the event of failure of any of the financial institutions where we maintain our cash and cash equivalents, there can be no assurance that we would be able to access uninsured funds in a timely manner or at all. Any inability to access or delay in accessing these funds could adversely affect our business and financial position. We had no indebtedness as of June 30, 2026. ATM Program In May 2021, the Company entered into a sales agreement, or the Sales Agreement, with SVB Leerink Partners LLC, or SVB Leerink, as sales agent (the “Sales Agreement”), pursuant to which the Company may, from time to time, issue and sell common stock with an aggregate value of up to $75.0 million in “at-the-market” offerings, or the ATM, under the Company’s Registration Statement on Form S-3 (File No. 333-286122) filed with the SEC, on March 26, 2025. Sales of common stock, pursuant to the Sales Agreement, may be made in sales deemed to be an “at the market offering” as defined in Rule 415(a) of the Securities Act, including sales made directly through the Nasdaq Global Market or any other existing trading market for the Company’s common stock. In December 2025, the Company sold 3,928,571 shares of common stock under the Sales Agreement at a price of $1.40 per share, raising aggregate gross proceeds of $5.5 million before fees and expenses of $0.1 million. As of June 30, 2026, there was $69.5 million of our common stock remaining available for sale under our ATM. Stock Purchase Agreement On December 15, 2025, the Company entered into a Stock Purchase Agreement (the “Stock Purchase Agreement”) with Matrix Capital Master Fund, LP ("Matrix"), one of our then-stockholders. Pursuant to the Stock Purchase Agreement, the Company agreed to repurchase 7,500,000 shares of the Company’s common stock from Matrix at a price of $1.33 per share, representing a discount from the Company’s closing share price of $1.40 on December 12, 2025 (the “Repurchase”). The Repurchase closed on December 15, 2025. Cash Flows The following table summarizes our sources and uses of cash for the period presented: Six Months Ended June 30, 2026 2025 (in thousands) Net cash used in operating activities $ (70,192) $ (67,344) Net cash provided by investing activities 60,038 70,853 Net cash (used in) provided by financing activities (1,058) 189 Net (decrease) increase in cash and cash equivalents $ (11,212) $ 3,698 Operating Activities Net cash used in operating activities for the six months ended June 30, 2026 was $70.2 million, consisting primarily of our net loss of $77.6 million as we incurred expenses associated with research and development activities for our 36 product candidate and general and administrative activities, partially offset by changes in operating assets and liabilities of $1.0 million and non-cash adjustments of $6.4 million. Net cash used in operating activities for the six months ended June 30, 2025 was $67.3 million, consisting primarily of our net loss of $75.2 million as we incurred expenses associated with the restructuring event, research and development activities for our product candidates and incurred general and administrative expenses, as well as changes in operating assets and liabilities of $6.6 million and non-cash adjustments of $14.4 million. Investing Activities Net cash provided by investing activities for the six months ended June 30, 2026 of $60.0 million was primarily attributable to proceeds from maturities of marketable securities of $120.0 million, offset by net investment of excess cash of $59.9 million. Net cash provided by investing activities for the six months ended June 30, 2025 of $70.9 million was attributable to proceeds from maturities of marketable securities of $130.0 million and proceeds from sale of property and equipment of $0.6 million, offset by net investment of excess cash of $59.7 million. Financing Activities Net cash used in financing activities for the six months ended June 30, 2026 of $1.1 million resulted from cash used for the net-settlement of restricted stock unit vesting of $1.5 million partially offset by proceeds of $0.4 million from the issuance of common stock under equity incentive plans . Net cash provided by financing activities for the six months ended June 30, 2025 of $189 thousand was provided from the issuance of common stock under equity incentive plans. Funding Requirements Our future capital requirements will depend on many factors, including: •the clinical development of azenosertib for the treatment of oncology indications; •the preclinical and clinical development of other programs, resources allowing; •the development of a companion diagnostic with a partner in conjunction with our clinical development of azenosertib as a monotherapy for the treatment of Cyclin E1-positive PROC, if applicable, diagnostics tools for additional biomarkers for azenosertib and any future product candidates; •the costs of in-licensing or acquiring the rights to other products, product candidates or technologies; •the legal costs related to maintaining, expanding and protecting our intellectual property portfolio; •hiring additional personnel, if needed; •the costs to seek regulatory approval for azenosertib for the treatment of Cyclin E1-positive PROC and support our diagnostic partner's seeking regulatory approval of a companion diagnostic to identify patients with Cyclin E1-positive PROC, and resources allowing, seek regulatory approval of azenosertib for additional oncology indications, assuming supportive clinical data; and •the costs to seek regulatory approval for any future product candidates and, if needed, diagnostics tools for biomarkers associated with such product candidates, that successfully complete clinical development, resources allowing. 37 As of June 30, 2026, we have $4.1 million and $33.6 million in current and long-term lease liabilities, respectively. We believe that our existing cash, cash equivalents and marketable securities as of June 30, 2026 will be sufficient to fund our operating expenses and capital expenditure requirements into late 2027. We have based these estimates on assumptions that may prove to be imprecise, and we could utilize our available capital resources sooner than we expect. Because of the numerous risks and uncertainties associated with research, development and commercialization of pharmaceutical drugs, it is difficult to estimate with certainty the amount of our working capital requirements. Our future funding requirements will depend on many factors, including: •the progress, costs and results of our clinical trials and seeking regulatory and marketing authorizations for azenosertib as a treatment for patients with Cyclin E1-positive PROC and, resources allowing, any additional indications, and any future product candidates; •our efforts and costs to establish sales, marketing, and distribution infrastructure to commercialize azenosertib or any future product candidates for which we obtain approval; •the progress, costs and results to develop and commercialize a companion diagnostic to identify patients with Cyclin E1-positive PROC; •the progress, costs and results of additional research and preclinical studies in other research programs we initiate in the future and, if needed, of diagnostics tools for additional biomarkers for azenosertib and any future product candidates; •the costs and timing of process development and manufacturing scale-up activities associated with azenosertib and, resources allowing, our product candidates and other programs as we advance them through preclinical and clinical development; •our ability to establish and maintain strategic collaborations, licensing or other agreements and the financial terms of such agreements; •the extent to which we in-license or acquire rights to other products, product candidates or technologies; •the costs and timing of preparing, filing and prosecuting patent applications, maintaining and protecting our intellectual property rights and defending against any intellectual property-related claims; and •our ability to attract and retain skilled personnel. Further, our operating results may change in the future, and we may need additional funds to meet operational needs and capital requirements associated with such operating plans. Until such time as we can generate significant revenue from product sales, if ever, we plan to finance our operations through the sale of equity, debt financings or other capital sources, which may include collaborations with other companies or other strategic transactions. We currently have no credit facility or committed sources of capital. To the extent that we raise additional capital through the sale of equity or convertible debt securities, your ownership interest will be diluted, and the terms of these securities may include liquidation or other preferences that adversely affect your rights as a common stockholder. Debt financing and preferred equity financing, if available, may involve agreements that include covenants limiting or restricting our ability to take specific actions, such as incurring additional debt, making capital expenditures or declaring dividends. If we raise additional funds through other third-party funding, collaboration 38 agreements, strategic alliances, licensing arrangements or marketing and distribution arrangements, we may have to relinquish valuable rights to our technologies, future revenue streams, research programs or product candidates or grant licenses on terms that may not be favorable to us. If we are unable to raise additional funds through equity or debt financings when needed, we may be required to delay, limit, reduce or terminate our product development or future commercialization efforts or grant rights to develop and market products or product candidates that we would otherwise prefer to develop and market ourselves. Critical Accounting Estimates There have been no significant changes to our critical accounting estimates from our disclosure reported in “Critical Accounting Estimates” in the section titled “Management’s Discussion and Analysis of Financial Condition and Results of Operations” in our Annual Report on Form 10-K for the fiscal year ended December 31, 2025.