CYTK

This discussion and analysis should be read in conjunction with our financial statements and accompanying notes included elsewhere in this report. Operating results are not necessarily indicative of results that may occur in future periods. This report contains forward-looking statements indicating expectations about future performance and other forward-looking statements within the meaning of Section 27A of the Securities Act, Section 21E of the Exchange Act, and the Private Securities Litigation Reform Act of 1995, that involve risks and uncertainties. All statements other than statements of historical fact, including statements concerning our plans, objectives, goals, strategies, future events, future revenues or performance, financing needs, expectations, plans or intentions relating to clinical development, product candidates, the regulatory approval process, our commercialization efforts for MYQORZO, products and markets, and business trends and other information referred to under the “Risk Factors” and “Management’s Discussion and Analysis of Financial Condition and Results of Operations,” are forward-looking statements. In some cases, you can identify forward-looking statements by terms such as “anticipate,” “assume,” “believe,” “commitment,” “could,” “estimate,” “expect,” “forecast,” “intend,” “may,” “plan,” “potential,” “predict,” “project,” “should,” “target,” “will,” “would,” “seek” and similar expressions intended to identify forward-looking statements. We have made these statements in reliance on the safe harbor provisions of the Private Securities Litigation Reform Act of 1995. Forward-looking statements are subject to certain risks and uncertainties, which could cause actual results, outcomes, and the timing of events to differ materially from the results discussed in the forward-looking statements. In addition, these forward-looking statements are subject to the risks and uncertainties discussed in the “Risk Factors” section and elsewhere in this document. Such statements speak only as of the date on which they are made, and, except as required by law, we undertake no obligation to update any forward-looking statement to reflect events or circumstances after the date on which the statement is made or to reflect the occurrence of unanticipated events. New factors emerge from time to time, and it is not possible for us to predict which factors will arise. In addition, we cannot assess the impact of each factor on our business or the extent to which any factor, or combination of factors, may cause actual results to differ materially from those contained in any forward-looking statements. In addition, statements that “we believe” and similar statements reflect our beliefs and opinions on the relevant subject. These statements are based upon information available to us as of the date of this Quarterly Report on Form 10-Q, and while we believe such information forms a reasonable basis for such statements, such information may be limited or incomplete, and our statements should not be read to indicate that we have conducted an exhaustive inquiry into, or review of, all potentially available relevant information. These statements are inherently uncertain and investors are cautioned not to unduly rely upon these statements. Overview We are a biopharmaceutical company focused on discovering, developing and commercializing novel muscle activators and muscle inhibitors as potential treatments for debilitating diseases in which muscle performance is compromised and/or declining. We have discovered and are developing muscle-directed investigational medicines that may potentially improve the health span of people with devastating cardiovascular and neuromuscular diseases of impaired muscle function. Our first commercial product is MYQORZO® (aficamten), 5 mg, 10 mg, 15 mg, and 20 mg tablets, which the FDA approved in December 2025. MYQORZO is an allosteric and reversible inhibitor of cardiac myosin motor activity. The approval of MYQORZO included a risk evaluation and mitigation strategy program, otherwise known as a REMS, intended to support a favorable benefit-risk profile in light of the risk of heart failure due to systolic dysfunction. In patients with oHCM, myosin inhibition with MYQORZO reduces cardiac contractility and left ventricular outflow tract obstruction. MYQORZO became available for prescription to patients on or around January 27, 2026. In addition, in February 2026, the European Commission approved MYQORZO® (aficamten), 5 mg, 10 mg, 15 mg and 20 mg tablets for the treatment of symptomatic (New York Heart Association, NYHA, class II-III) oHCM in adult patients. In July 2026, the Medicines and Healthcare products Regulatory Agency (MHRA) granted MYQORZO marketing authorization across the United Kingdom for the treatment of symptomatic oHCM in adult patients. Moreover, in December 2025, the China National Medical Products Administration approved MYQORZO for the treatment of adults with (New York Heart Association class II-III) oHCM, to improve exercise capacity and symptoms. Behind MYQORZO, we are making disciplined pipeline investments in investigational products that are at discovery, preclinical and clinical stages of research and development. All our research and development activities relate to the biology of muscle function and have evolved from our knowledge and expertise regarding the cytoskeleton, a complex biological infrastructure that plays a fundamental role within every human cell. As a leader in muscle biology and the mechanics of muscle performance, we are discovering and developing small molecule drug candidates specifically engineered to impact muscle function and contractility with the objective of building a sustainable specialty biopharmaceutical business. 23 Table of Contents Our specific focus on the biology of the cytoskeleton distinguishes us from other biopharmaceutical companies and potentially positions us to identify or discover and develop and commercialize novel therapeutics that may be useful for the treatment of severe diseases and medical conditions. We intend to leverage our experience in muscle contractility to expand our current pipeline and expect to identify additional potential drug candidates that may be suitable for clinical development and commercialization. Cytokinetics’ Marketed Product: MYQORZO® MYQORZO® (aficamten), is a novel, oral, small molecule cardiac myosin inhibitor that our scientists discovered for the treatment of symptomatic oHCM. MYQORZO was designed to reduce the hypercontractility associated with HCM. In preclinical models, MYQORZO reduces myocardial contractility by binding directly to cardiac myosin at a distinct and selective allosteric binding site, thereby preventing myosin from entering a force producing state. MYQORZO reduces the number of active actin-myosin cross bridges during each cardiac cycle and consequently reduces myocardial contractility. HCM is the most common monogenic inherited cardiovascular disorder, with well over 300,000 patients diagnosed in the U.S. However, there are an estimated 400,000-800,000 additional patients who remain undiagnosed. The diagnosis rate for oHCM is growing at approximately the same rate as the population, while the diagnosis rate for nHCM has been increasing with recent year-over-year growth estimated to be in the low double digits. Estimates vary but we believe approximately half of patients with HCM have oHCM, in which the thickening of the cardiac muscle leads to LVOT obstruction, while the remaining HCM patients have nHCM, in which blood flow is not impacted, but the heart muscle is still thickened. HCM is fairly evenly split across gender and while patients are typically diagnosed in their early 40s, the average age of an oHCM patient is in the early 60s. People with HCM are at high risk of also developing cardiovascular complications, including atrial fibrillation, stroke and mitral valve disease. People with HCM are at risk for potentially fatal ventricular arrhythmias, and HCM is one of the leading causes of sudden cardiac death in younger people or athletes. A subset of patients with HCM are at high risk of progressive disease leading to dilated cardiomyopathy and heart failure necessitating cardiac transplantation. In December 2025, the FDA approved MYQORZO, 5 mg, 10 mg, 15 mg, and 20 mg tablets for the treatment of adults with symptomatic oHCM to improve functional capacity and symptoms. MYQORZO is an allosteric and reversible inhibitor of cardiac myosin motor activity. The approval of MYQORZO included a risk evaluation and mitigation strategy (REMS) program intended to support a favorable benefit-risk profile in light of the risk of heart failure due to systolic dysfunction. In addition, in February 2026, the European Commission approved MYQORZO® (aficamten), 5 mg, 10 mg, 15 mg and 20 mg tablets for the treatment of symptomatic (New York Heart Association, NYHA, class II-III) obstructive hypertrophic cardiomyopathy (oHCM) in adult patients. Moreover, in December 2025, the China National Medical Products Administration approved MYQORZO for the treatment of adults with (New York Heart Association class II-III) oHCM, to improve exercise capacity and symptoms. We commenced commercial sales of MYQORZO in the United States in the first quarter of 2026. Our market research supports our belief that MYQORZO will be highly competitive amongst cardiac myosin inhibitors, potentially eventually achieving a greater than 50% market share in the United States but also growing the cardiac myosin inhibitor category overall. The commercial prospects for MYQORZO depend on three launch drivers: clinical evidence, our experience with HCPs and patients, and the approved label. Clinical evidence shows that treatment with MYQORZO in adult patients with symptomatic oHCM led to rapid and sustained reduction in obstruction and improvement in symptoms. Our experience with HCPs and patients informed our Cardiac Account Specialist (CAS) design, including its single point of contact and accountability for HCP's with our field sales organization and our bespoke patient support program, MYQORZO and You™. We believe the MYQORZO prescribing information allows for flexibility to titrate as early as two weeks, with echo assessment within 2 to 8 weeks following dose initiation and any subsequent dose changes, and importantly, a patient's dose may be titrated as needed after each echo with no delay. In the European Union, we commenced commercialization activities in Germany in the second quarter of 2026 to be followed by other major European countries. In July 2026, the Medicines and Healthcare products Regulatory Agency (MHRA) granted MYQORZO marketing authorization across the United Kingdom for the treatment of symptomatic oHCM in adult patients. We expect the UK product launch later this year. MYQORZO is also approved in China for the treatment of adults with (New York Heart Association class II-III) oHCM, to improve exercise capacity and symptoms. Sanofi has the commercial rights for China and Taiwan and commenced commercialization of MYQORZO in the first quarter of 2026. Finally, in January 2026 we submitted, and the FDA subsequently accepted for filing, a supplemental NDA for MYQORZO to the FDA requesting to include the results of MAPLE-HCM, a Phase 3 randomized, double blind, active-comparator clinical trial of aficamten as monotherapy compared to metoprolol as a monotherapy in patients with obstructive HCM, in the label. The FDA assigned a standard review classification to the sNDA with a PDUFA date of November 14, 2026. 24 Table of Contents Research and Development Programs Our research and development activities related to muscle contractility include our cardiac muscle contractility programs and our skeletal muscle contractility programs. We also conduct research and development on novel treatments for disorders involving muscle function beyond muscle contractility. We are leveraging our current understandings of muscle biology to investigate new ways of modulating other aspects of muscle function for other potential therapeutic applications. Specialty Cardiology Programs Our specialty cardiology program is focused on the cardiac sarcomere, the basic unit of muscle contraction in the heart. The cardiac sarcomere is a highly ordered cytoskeletal structure composed of cardiac myosin, actin and a set of regulatory proteins. Cardiac myosin is the cytoskeletal motor protein in the cardiac muscle cell. It is directly responsible for converting chemical energy into the mechanical force, resulting in cardiac muscle contraction. Our most advanced cardiac program, MYQORZO (aficamten), is based on the hypothesis that inhibitors of cardiac myosin may attenuate the hyperdynamic contraction resulting from pathologic mutations in the sarcomere that lead to hypertrophic cardiomyopathies. MYQORZO was approved in the U.S., Europe and China for the treatment of adults with symptomatic oHCM. We submitted a supplemental NDA to the FDA in January 2026 with the intent to include the results of MAPLE-HCM (a Phase 3 randomized, double blind, active-comparator clinical trial of aficamten as monotherapy compared to metoprolol as a monotherapy in patients with obstructive HCM) in the label. Finally, as described below, we evaluated aficamten for the potential treatment of adults with symptomatic nHCM in ACACIA-HCM. In addition, omecamtiv mecarbil is our late-stage clinical program directed to the hypothesis that activators of cardiac myosin may target the underlying deficit of cardiac contractility in heart failure with severely reduced ejection fraction and address certain adverse properties of existing positive inotropic agents. Omecamtiv mecarbil is a novel cardiac myosin activator that works by directly stimulating the activity of the cardiac myosin motor protein, without increasing the intracellular calcium concentration. This drug candidate accelerates the rate-limiting step of the myosin enzymatic cycle and shifts it in favor of the force-producing state. Rather than increasing the velocity of cardiac contraction, this mechanism lengthens the systolic ejection time, which results in increased cardiac function in a potentially more oxygen-efficient manner. Aficamten Aficamten is a novel, oral, small molecule cardiac myosin inhibitor that our scientists discovered for the treatment of HCM. Aficamten arose from an extensive chemical optimization program conducted with attention to therapeutic index and pharmacokinetic properties. Aficamten was designed to reduce the hypercontractility associated with HCM. In preclinical models, aficamten reduces myocardial contractility by binding directly to cardiac myosin at a distinct and selective allosteric binding site, thereby preventing myosin from entering a force producing state. Aficamten reduces the number of active actin-myosin cross bridges during each cardiac cycle and consequently reduces myocardial contractility. This mechanism of action may be therapeutically effective in conditions characterized by excessive hypercontractility, such as HCM. The preclinical pharmacokinetics of aficamten were characterized, evaluated and optimized for potential rapid onset, ease of titration and rapid symptom relief. The development program for aficamten has assessed its potential as a treatment to improve exercise capacity and relieve symptoms in patients with oHCM. In addition, development work is ongoing to assess aficamten for its potential long-term effects on cardiac structure and function. SEQUOIA-HCM Aficamten was evaluated in SEQUOIA-HCM, a positive pivotal Phase 3 clinical trial in patients with symptomatic oHCM. The results from SEQUOIA-HCM showed that treatment with aficamten for 24 weeks significantly improved exercise capacity compared to placebo. Statistically significant and clinically meaningful improvements were also observed in all 10 prespecified secondary endpoints, with functional and symptomatic improvements occurring within two weeks of initiating treatment with aficamten and sustained throughout the treatment period. The safety of aficamten was consistent with previous trials. MAPLE-HCM Aficamten was also evaluated in MAPLE-HCM, a Phase 3 randomized, double blind, active-comparator clinical trial of aficamten as monotherapy compared to metoprolol as a monotherapy in patients with obstructive HCM which demonstrated a statistically significant improvement in peak oxygen uptake (pVO2) from baseline to Week 24 for aficamten compared to metoprolol. The safety of aficamten was consistent with previous trials. 25 Table of Contents ACACIA-HCM Aficamten was also evaluated in ACACIA-HCM, a Phase 3 randomized, double blind clinical trial in patients with symptomatic nHCM. ACACIA-HCM met both dual primary endpoints, demonstrating statistically significant improvements from baseline to Week 36 compared to placebo in both Kansas City Cardiomyopathy Questionnaire Clinical Summary Score (KCCQ) and maximal exercise performance (pVO2). The improvement in KCCQ was robust and consistent throughout the treatment period in participants on aficamten. Following washout, KCCQ decreased for participants on aficamten to match the placebo group. At Week 36, pVO2 increased for participants on aficamten, while it remained unchanged for participants on placebo, consistent with prior trials of aficamten in oHCM. Statistically significant (p<0.001) improvements compared to placebo were observed in key secondary endpoints including the proportion of participants with improvements in NYHA Functional Class, the composite z-score of ventilatory efficiency and pVO2, and NT-proBNP. There were no new safety signals identified. Left ventricular ejection fraction (LVEF) <50% occurred in 27 (10%) participants taking aficamten and 1% in participants taking placebo. Two participants on aficamten experienced a serious adverse event of heart failure associated with LVEF <50%. Treatment interruptions due to LVEF <40% occurred in 3% of participants taking aficamten. Aficamten continues to be evaluated in CEDAR-HCM, a clinical trial of aficamten in a pediatric population with oHCM; and FOREST-HCM, an open-label extension clinical study of aficamten in patients with HCM. We expect to complete enrollment in the adolescent cohort of CEDAR-HCM in the third quarter of 2026. Omecamtiv mecarbil We are developing omecamtiv mecarbil as a potential treatment across the continuum of care in heart failure with severely reduced ejection fraction both for use in the hospital setting and for use in the outpatient setting. Omecamtiv mecarbil is a selective, small molecule cardiac myosin activator, the first of a novel class of myotropes designed to directly target the contractile mechanisms of the heart, binding to and recruiting more cardiac myosin heads to interact with actin during systole. Omecamtiv mecarbil is designed to increase the number of active actin-myosin cross bridges during each cardiac cycle and consequently augment the impaired contractility that is associated with heart failure with reduced ejection fraction, or HFrEF. GALACTIC-HF GALACTIC-HF is a Phase 3 cardiovascular outcomes clinical trial of omecamtiv mecarbil that was conducted by Amgen in collaboration with Cytokinetics. The primary objective of this double-blind, randomized, placebo-controlled multicenter clinical trial was to determine if treatment with omecamtiv mecarbil when added to standard of care is superior to standard of care plus placebo in reducing the risk of cardiovascular death or heart failure events in patients with high-risk chronic heart failure and reduced ejection fraction. The results of GALACTIC-HF showed a statistically significant effect of treatment with omecamtiv mecarbil to reduce risk of the primary composite endpoint of CV death or heart failure events (heart failure hospitalization and other urgent treatment for heart failure) compared to placebo in patients treated with standard of care after a median duration of follow up of 21.8 months. COMET-HF Based on supplemental and subgroup analyses suggesting that certain biologically plausible subgroups of patients treated with omecamtiv mecarbil in GALACTIC-HF may have benefited more than the general patient population in the trial due to the high unmet need in patients with heart failure with severely reduced ejection fraction, we are continuing the development program for omecamtiv mecarbil. In the fourth quarter of 2024, we commenced patient enrollment in COMET-HF (Confirmation of Omecamtiv Mecarbil Efficacy Trial in Heart Failure), a Phase 3 multi-center, double-blind, randomized, placebo-controlled trial to assess the efficacy and safety of omecamtiv mecarbil in patients with symptomatic HFrEF with severely reduced ejection fraction. The primary endpoint of COMET-HF is the time to first event in the primary composite endpoint of cardiovascular death, first heart failure event, LVAD implantation or cardiac transplantation, or stroke. COMET-HF is expected to enroll approximately 1,800 patients randomized on a 1:1 basis to receive omecamtiv mecarbil or placebo for up to 48 weeks. Ulacamten (f/k/a CK-586) Ulacamten is a novel, selective, oral, small molecule cardiac myosin inhibitor designed to reduce the hypercontractility associated with heart failure with preserved ejection fraction, or HFpEF. Approximately half of the estimated 6.7 million patients in the United States with heart failure have HFpEF, and the prevalence of HFpEF is increasing. A subset of HFpEF patients with hypercontractility, ventricular hypertrophy, elevated biomarkers and symptoms of heart failure may benefit from treatment with a cardiac sarcomere inhibitor. Approximately 75% of patients with HFpEF die within five years of initial hospitalization, and 84% are re-hospitalized. Despite broad use of standard treatments and advances in care, the prognosis for patients with heart failure is poor. 26 Table of Contents AMBER-HFpEF In the fourth quarter of 2024, we announced the design of AMBER-HFpEF (Assessment of Ulacamten in a Multi-Center, Blinded Evaluation of Safety and Tolerability Results in HFpEF), a Phase 2 randomized, placebo-controlled, double-blind, multi-center, dose-finding clinical trial in patients with symptomatic HFpEF with left ventricular ejection fraction ≥ 60%. The primary objective is to evaluate the safety and tolerability profile of ulacamten compared to placebo. The secondary objectives include assessing the effect of ulacamten on LVEF and NT-proBNP, its pharmacokinetics, and its pharmacokinetic/pharmacodynamic relationship. AMBER-HFpEF is currently enrolling patients, and we expect to complete enrollment in cohort 2 of the study by the end of 2026. Neuromuscular Program Our neuromuscular program is focused on the activation of the skeletal sarcomere, the basic unit of skeletal muscle contraction. The skeletal sarcomere is a highly ordered cytoskeletal structure composed of skeletal muscle myosin, actin, and a set of regulatory proteins, which include the troponins and tropomyosin. This program leverages our expertise developed in our ongoing discovery and development of cardiac sarcomere activator. In the fourth quarter of 2024, we announced that the first participants have been dosed in a Phase 1 randomized, double-blind, placebo-controlled, multi-part, single and multiple ascending dose clinical study of CK-089 in healthy human participants. CK-089 is a fast skeletal muscle troponin activator with potential therapeutic application to a specific type of muscular dystrophy and other conditions of impaired muscle function. The primary objective of this Phase 1 randomized, double-blind, placebo-controlled, multi-part single and multiple ascending dose clinical study is to evaluate the safety, tolerability and pharmacokinetics of CK-089 when administered orally as single or multiple doses to healthy participants. The study design includes single ascending dose cohorts and multiple-dose ascending cohorts comprised of 10 participants each. Our clinical development program for CK-089 was subject to a partial clinical hold from FDA that limited our ability to dose patients at doses anticipated to result in plasma exposures higher than certain levels. FDA subsequently lifted the partial clinical trial hold in the second quarter of 2026, permitting us to continue our development program as intended. Results of Operations Revenues Our revenues since inception were primarily from our collaboration partners. We did not generate any revenue from commercial product sales prior to the year ended December 31, 2025. MYQORZO for adults with symptomatic oHCM was approved by the FDA in December 2025 and our first commercial sale of MYQORZO occurred in the first quarter of 2026. Revenues for the three and six months ended June 30, 2026 and 2025, were as follows (in thousands): Three Months Ended Six Months Ended June 30, 2026 June 30, 2025 Decrease June 30, 2026 June 30, 2025 Decrease Net product revenue $ 25,334 $ — $ 25,334 $ 30,123 $ — $ 30,123 Collaboration revenues 3,290 2,416 874 5,927 3,995 1,932 License and milestone revenues — 64,353 (64,353 ) 11,929 64,353 (52,424 ) Total revenues $ 28,624 $ 66,769 $ (38,145 ) $ 47,979 $ 68,348 $ (20,369 ) Net product revenue was recorded for our commercial sales of MYQORZO commencing in the last week of January 2026, for the three and six months ended June 30, 2026. Net product revenue by geographic area for the three and six months ended June 30, 2026 and 2025, were as follows (in thousands): Three Months Ended Six Months Ended June 30, 2026 June 30, 2025 June 30, 2026 June 30, 2025 United States $ 22,964 $ — $ 27,753 $ — Europe 2,370 — 2,370 — Total net product revenue $ 25,334 $ — $ 30,123 $ — Collaboration revenues for the three and six months ended June 30, 2026 and 2025 were primarily from Bayer under the Bayer License Agreement related to certain research and development cost reimbursements. 27 Table of Contents License and milestone revenues for the three and six months ended June 30, 2026 were from Bayer related to the first commercial sale of MYQORZO in the United States. License and milestone revenues for the three and six months ended June 30, 2025 were primarily from Bayer related to the delivery of the license and completion of the technology transfer totaling $52.4 million and certain clinical milestone achievements totaling $11.8 million. As of June 30, 2026, the accounts receivable, net balance was $24.4 million comprised of $2.5 million related to Bayer and $0.4 million related to Sanofi. The remaining $21.5 million receivable is associated with product revenue. Operating expenses Three Months Ended Six Months Ended June 30, 2026 June 30, 2025 Increase June 30, 2026 June 30, 2025 Increase Research and development $ 97,807 $ 110,138 $ (12,331 ) $ 193,332 $ 208,400 $ (15,068 ) Selling, general and administrative 104,397 65,721 38,676 209,293 123,090 86,203 Cost of goods sold 2,731 — 2,731 2,891 — 2,891 Collaboration cost of revenues (a) 2,861 2,416 445 5,253 3,995 1,258 Total operating expenses $ 207,796 $ 178,275 $ 29,521 $ 410,769 $ 335,485 $ 75,284 (a) Includes costs incurred in connection with manufacturing drug supplies for collaboration partners. Operating expenses included stock-based compensation expense of $35.7 million and $27.5 million for the three months ended June 30, 2026 and 2025, respectively, and $66.1 million and $51.1 million for the six months ended June 30, 2026 and 2025, respectively. Research and development expenses We incur research and development expenses that consist of employee compensation, supplies and materials, costs for consultants, contract research, clinical manufacturing and facilities and depreciation costs. Research and development expenses for the three and six months ended June 30, 2026 and 2025, were as follows (in thousands): Three Months Ended Six Months Ended June 30, 2026 June 30, 2025 Decrease June 30, 2026 June 30, 2025 Decrease External costs: Aficamten $ 14,853 $ 27,490 $ (12,637 ) $ 35,960 $ 55,758 $ (19,798 ) Omecamtiv Mecarbil 8,843 3,967 4,876 14,396 7,564 6,832 Other programs 5,250 3,025 2,225 8,403 6,398 2,005 Unallocated 10,804 21,213 (10,409 ) 17,530 29,553 (12,023 ) Total external costs 39,750 55,695 (15,945 ) 76,289 99,273 (22,984 ) Internal costs: Employee related 45,267 40,593 4,674 90,799 80,320 10,479 Facilities, lab supplies and other 12,790 13,850 (1,060 ) 26,244 28,807 (2,563 ) Total internal costs 58,057 54,443 3,614 117,043 109,127 7,916 Total research and development expenses $ 97,807 $ 110,138 $ (12,331 ) $ 193,332 $ 208,400 $ (15,068 ) Research and development expenses for the three months ended June 30, 2026 decreased by $12.3 million compared to the three months ended June 30, 2025. The decrease was primarily due to higher clinical trial activity, supply chain costs and medical affairs activities in 2025 partially offset by higher personnel-related costs in 2026. Research and development expenses for the six months ended June 30, 2026 decreased by $15.1 million compared to the six months ended June 30, 2025. The decrease was primarily due to higher clinical trial activity, supply chain costs and medical fairs activities in 2025 partially offset by higher personnel-related costs in 2026. Our development program for aficamten continues with CEDAR-HCM, our placebo-controlled and open-label extension clinical trial to evaluate the efficacy, pharmacokinetics (PK) and safety of aficamten in a pediatric population with symptomatic oHCM. Additionally, we have FOREST-HCM which is an open label extension study designed to assess the long-term safety and tolerability of aficamten in patients with HCM. 28 Table of Contents We continue to develop omecamtiv mecarbil in COMET-HF, a Phase 3 clinical trial of omecamtiv mecarbil in patients with symptomatic HFrEF with severely reduced ejection fraction. The intention of the $100 million RP OM Loan Agreement was to partially cover the costs of COMET-HF. We continue to develop ulacamten in AMBER-HFpEF, a Phase 2 clinical trial of ulacamten in patients with symptomatic HFpEF, in which patient enrollment commenced in the first quarter of 2025. The $50 million in proceeds from the RP Ulacamten RPA are intended to offset expenses related to the conduct of AMBER-HFpEF. If the results of AMBER-HFpEF are supportive of continuing the development of ulacamten and commencing a Phase 3 clinical trial, Royalty Pharma has the option to fund potentially 50% of the continued development of ulacamten up to $150 million, subject to Royalty Pharma’s opt-in right to acquire an additional 3.5% revenue interest in our or our licensee’s future worldwide net sales of drug products containing ulacamten. In the fourth quarter of 2024, we announced that the first participants have been dosed in a Phase 1 randomized, double-blind, placebo-controlled, multi-part, single and multiple ascending dose clinical study of CK-089 in healthy human participants. CK-089 is a fast skeletal muscle troponin activator with potential therapeutic application to a specific type of muscular dystrophy and other conditions of impaired muscle function. The primary objective of this Phase 1 randomized, double-blind, placebo-controlled, multi-part single and multiple ascending dose clinical study is to evaluate the safety, tolerability and pharmacokinetics of CK-089 when administered orally as single or multiple doses to healthy participants. The study design includes single ascending dose cohorts and multiple-dose ascending cohorts comprised of 10 participants each. Our clinical development program for CK-089 was subject to a partial clinical hold from FDA. FDA subsequently lifted the partial clinical trial hold in the second quarter of 2026, permitting us to continue our development program as intended. We expect that research and development expenses will be flat to declining in 2026 relative to 2025 due to the completion of MAPLE-HCM and ACACIA-HCM, partially offset by the continuation of COMET-HF, AMBER HFpEF, CEDAR-HCM, FOREST-HCM and any additional clinical trials we may choose to undertake in connection with CK-089 or any other drug candidates. Selling, general and administrative expenses Selling, general and administrative expenses consist primarily of personnel costs, facilities and overhead costs, and selling, marketing and advertising expenses, as well as other general and administrative costs related to finance, human resources, legal and other administrative activities. Selling, general and administrative expenses for the three and six months ended June 30, 2026 and 2025, were as follows (in thousands): Three Months Ended Six Months Ended June 30, 2026 June 30, 2025 Increase June 30, 2026 June 30, 2025 Increase Total selling, general and administrative expenses $ 104,397 $ 65,721 $ 38,676 $ 209,293 $ 123,090 $ 86,203 Selling, general and administrative expenses for the three months ended June 30, 2026 increased by $38.7 million from the three months ended June 30, 2025, primarily due to external costs associated with the commercial launch of MYQORZO and higher personnel related costs, including stock-based compensation. Selling, general and administrative expenses for the six months ended June 30, 2026 increased by $86.2 million from the six months ended June 30, 2025, primarily due to external costs associated with the commercial launch of MYQORZO and higher personnel related costs, including stock-based compensation. We expect selling, general and administrative expenses to increase significantly in 2026. With the approval of MYQORZO in the United States, we expect to incur additional expenses for commercial activities, including, but not limited to, the full year impact of the U.S. sales force, training and education, the implementation of compliance systems, patient support programs, sales and marketing expenses and pre-commercial activities to to support the commercial launch of MYQORZO in nHCM. In addition, the European Commission approved MYQORZO for the treatment of adults with symptomatic oHCM, (NYHA class II-III), and therefore, we expect to incur similar expenses for commercial readiness activities in Europe but with additional expenses for the establishment of a corporate infrastructure to enable commercialization activities in key European markets, beginning in Germany with other major European markets to follow. 29 Table of Contents Cost of Goods Sold Costs of goods sold for the three and six months ended June 30, 2026 and 2025, were as follows (in thousands): Three Months Ended Six Months Ended June 30, 2026 June 30, 2025 Increase June 30, 2026 June 30, 2025 Increase Total cost of goods sold $ 2,731 $ — $ 2,731 $ 2,891 $ — $ 2,891 We received FDA approval for MYQORZO on December 19, 2025 and began capitalizing inventories upon FDA approval. Costs incurred prior to approval were recorded as research and development expense in our condensed consolidated statement of operations and comprehensive loss. As a result, cost of goods sold for the next several quarters are expected to reflect a lower average per unit cost of materials. Cost of goods sold in the second quarter of 2026 reflects a charge related to drug supply optimization which accounts for nearly the entire amount. Collaboration Cost of Revenues Collaboration cost of revenues includes cost reimbursements as well as costs incurred in connection with manufacturing drug supplies for collaboration partners. Collaboration of cost of revenues for the three and six months ended June 30, 2026 and 2025, were as follows (in thousands): Three Months Ended Six Months Ended June 30, 2026 June 30, 2025 Increase June 30, 2026 June 30, 2025 Increase Total collaboration cost of revenues $ 2,861 $ 2,416 $ 445 $ 5,253 $ 3,995 $ 1,258 Collaboration cost of revenues for the three and six months ended June 30, 2026 and 2025 were primarily from Bayer under the Bayer License Agreement related to certain research and development cost reimbursements. Interest Expense Interest expense for the three and six months ended June 30, 2026 and 2025, was as follows (in thousands): Three Months Ended Six Months Ended June 30, 2026 June 30, 2025 Increase June 30, 2026 June 30, 2025 Increase Term loans $ 8,914 $ 5,252 $ 3,662 $ 17,659 $ 8,370 $ 9,289 2026 Notes 117 240 (123 ) 355 477 (122 ) 2027 Notes 1,452 5,542 (4,090 ) 2,886 11,014 (8,128 ) 2031 Notes 4,075 — 4,075 8,102 — 8,102 Other 96 50 46 171 91 80 Total interest expense $ 14,654 $ 11,084 $ 3,570 $ 29,173 $ 19,952 $ 9,221 Term loan interest expense is related to the RP Multi Tranche Loan and increased year over year due to four tranches of interest expense being incurred in first quarter of 2026 for Tranches 1, 4, 5 and 6 compared to two tranches in the first quarter of 2025 related to Tranche 1 and 6. In September 2025, we issued the 2031 Notes and used the net proceeds and common stock to partially repurchase the 2027 Notes. Due to the balance of the 2027 Notes declining in the third quarter of 2025, interest expense declined year over year. There will be no additional interest on the 2026 Notes subsequent to June 30, 2026 since they have been fully redeemed. Interest expense in 2026 is expected to increase further because of the $100 million drawn in October 2025 for Tranche 5 which will be outstanding for the entirety of 2026. Interest expense may increase further if we draw on Tranche 7. Non-cash interest expense on liabilities related to revenue participation right purchase agreements Non-cash interest expense results from the accretion of our liabilities to RPFT and RP ICAV related to the sale of future royalties under the RP OM RPA and the RP Aficamten RPA, respectively. 30 Table of Contents Non-cash interest expense on liability related to the RP OM RPA and the RP Aficamten RPA for the three and six months ended June 30, 2026 and 2025 were as follows (in thousands): Three Months Ended Six Months Ended June 30, 2026 June 30, 2025 Increase June 30, 2026 June 30, 2025 Increase RP OM Liability $ — $ 41 $ (41 ) $ — $ 82 $ (82 ) RP Aficamten Liability 20,177 13,140 7,037 38,993 27,177 11,816 Total non-cash interest expense recognized $ 20,177 $ 13,181 $ 6,996 $ 38,993 $ 27,259 $ 11,734 The carrying amount of the RP Aficamten Liability is based on our estimate of the future royalties to be paid pursuant to RP Aficamten RPA over the life of the arrangement as discounted using an imputed rate of interest. The imputed rate of interest on the carrying value of the RP Aficamten Liability was approximately 26.1% as of June 30, 2026 and 20.5% as of June 30, 2025. The carrying amount of the RP OM Liability is based on our estimate of the future royalties to be paid pursuant to RP OM RPA over the life of the arrangement as discounted using an imputed rate of interest. The excess of future estimated royalty payments over the $92.3 million of allocated proceeds, less issuance costs, is recognized as non-cash interest expense using the effective interest method. The imputed rate of interest on the carrying value of the RP OM Liability is reassessed periodically and is not reduced below 0%. The imputed rate of interest on the carrying value of the RP OM Liability was 0.0% as of June 30, 2026 and approximately 0.1% as of June 30, 2025. We review our assumptions on a regular basis and our estimates may change in the future as we refine and reassess our assumptions. Interest and Other Income, net Interest and other income, net for the three and six months ended June 30, 2026 and 2025 consisted primarily of interest income generated from our cash, cash equivalents and investments. Change in fair value liabilities related to RPI transactions and derivative liabilities reflected on the Condensed Consolidated Statement of Operations. The change in fair value liabilities related to the RPI transactions (RP OM Loan Agreement and RP Ulacamten RPA) and the derivative liabilities for the RP Multi Tranche Loan Agreement for the three and six months ended June 30, 2026 and 2025 were as follows (in thousands): Three Months Ended Six Months Ended June 30, 2026 June 30, 2025 Increase June 30, 2026 June 30, 2025 Increase RP Ulacamten RPA $ 300 $ (300 ) $ 600 $ 500 $ — $ 500 RP OM Loan 2,100 (14,300 ) 16,400 300 (10,700 ) 11,000 RP Multi Tranche Loan Agreement Derivatives (1,100 ) 3,000 (4,100 ) 400 2,600 (2,200 ) Total change in fair value liabilities $ 1,300 $ (11,600 ) $ 12,900 $ 1,200 $ (8,100 ) $ 9,300 The fair values of the liabilities related to RPI transactions (RP OM Loan Agreement and RP Ulacamten RPA) are based on significant unobservable inputs, including the probability of clinical success and regulatory approval based on historical industry success rates for product development specific to cardiovascular products, the estimated date of a product launch, estimates of pricing, sales ramp, variables for the timing of the related events, probability of change of control, and discount rates (which ranged from 14% to 17% and 12% to 17% for the three and six months ended June 30, 2026, respectively, and 10% to 18% for the three and six months ended June 30, 2025), which are deemed to be Level 3 inputs in the fair value hierarchy. As products containing omecamtiv mecarbil and ulacamten have not yet been commercialized, the estimates are highly subjective. For example, assumed increases in the probability of the clinical success for the programs for omecamtiv mecarbil or ulacamten could increase the value of the liabilities. Similarly, assumed decreases in the discount rates used in the fair value measurements could also increase the value of the liabilities at period end. 31 Table of Contents The fair values of the derivative liabilities are determined using the probability-weighted expected return method and the “with and without” method. The fair values are based on significant unobservable inputs, including the probability of change of control, the probability of default (less than 10%), discount rates (ranging from 14% to 15% and 12% to 15% for the three and six months ended June 30, 2026, respectively, and 10% to 12% and 10% to 14% for the three and six months ended June 30, 2025, respectively) and other factors. The total change in the estimated fair value liabilities for the three and six months ended June 30, 2026 was primarily driven by changes in the discount rates used in the valuation of the 2024 RP OM Loan and the derivatives associated with the RP Multi Tranche Loan Agreement. Liquidity and Capital Resources Our cash, cash equivalents, and investments and a summary of our borrowings and working capital as of June 30, 2026 and December 31, 2025 are summarized as follows (in thousands): June 30, 2026 December 31, 2025 Financial assets: Cash and cash equivalents $ 255,271 $ 122,518 Short-term investments 910,415 759,703 Long-term investments 538,317 335,048 Total cash, cash equivalents, and marketable securities $ 1,704,003 $ 1,217,269 Borrowings: Term loans (including related derivative liabilities measured at fair value) $ 306,260 $ 297,644 Convertible notes, net 871,527 890,618 Liabilities related to RPI transactions measured at fair value 136,400 137,200 Total borrowings $ 1,314,187 $ 1,325,462 Working capital: Current assets $ 1,208,487 $ 916,975 Current liabilities 181,429 202,452 Working capital $ 1,027,058 $ 714,523 The following table shows a summary of our cash flows for the periods set forth below (in thousands): Six Months Ended June 30, 2026 June 30, 2025 Net cash used in operating activities $ (305,297 ) $ (259,853 ) Net cash (used in) provided by investing activities (361,506 ) 158,837 Net cash provided by financing activities 800,627 83,287 Total $ 133,824 $ (17,729 ) 32 Table of Contents Sources and Uses of Cash We funded our operations and capital expenditures with proceeds primarily from private and public sales of our equity securities, royalty monetization agreements, and revenue interest agreements, strategic alliances, long-term debt, other financings and interest on investments. We have generated significant operating losses since our inception. Our expenditures have historically been primarily related to research and development activities but have recently and will increasingly relate to our commercial readiness activities and general commercialization activities of our drug products. In December 2025, the FDA approved MYQORZO, 5 mg, 10 mg, 15 mg and 20 mg tablets for the treatment of adults with symptomatic oHCM to improve functional capacity and symptoms, with sales of MYQORZO commencing in the first quarter of 2026. Product was launched in Germany and China in the first half of 2026. Accordingly, we will be increasingly relying on revenues generated from commercial sales of MYQORZO and/or traditional financing activities to fund our operations and cash expenditures. Cash Flows Used in Operating Activities Net cash used in operating activities of $305.3 million and $259.9 million in the six months ended June 30, 2026 and 2025, respectively, was largely due to ongoing research and development activities and selling, general and administrative expenses to support commercial readiness and launch of MYQORZO. In future quarters fluctuations in accounts receivable and inventories will impact cash flows used in operating activities. Net loss for the six months ended June 30, 2026 and 2025 included, among other items: stock-based compensation, interest expense on liabilities related to revenue participation right purchase agreements and debt, and/or changes in fair values related to derivative liabilities and liabilities related to RPI Transactions. Cash Flows Provided by Investing Activities Net cash used in investing activities of $361.5 million in the six months ended June 30, 2026 was primarily due to maturities of investments offset by purchases of investments and property, plant and equipment. Net cash provided by investing activities of $158.8 million in the six months ended June 30, 2025 was primarily due to purchases of investments and property, plant and equipment offset by maturities of investments. Cash Flows Provided by Financing Activities Net cash provided by financing activities of $800.6 million in the six months ended June 30, 2026 was primarily due to $760.1 million of net proceeds from a public offering in May 2026 in addition to net proceeds from stock-based award activities, offset by repayment of RP Multi Tranche Term Loan. Net cash provided by financing activities of $83.3 million in the six months ended June 30, 2025 was primarily attributable to $75.0 million in proceeds from the drawing on Tranche 4 of the RP Multi Tranche Term Loan and net proceeds from stock-based award activities, offset by payments related to the RP Multi Tranche Term Loan. 2024 Royalty Pharma Transactions In May 2024, we entered into a series of financing agreements with affiliates of Royalty Pharma, including the RP OM Loan Agreement, the RP Ulacamten RPA, the 2022 RP Multi Tranche Loan Agreement Amendment, the RP Aficamten RPA Amendment, and the RP Stock Purchase Agreement for a private placement of common stock concurrent with our underwritten public offering of common stock. The RP OM Loan Agreement provides for a loan in the principal amount of $100.0 million that was drawn at the closing with no remaining amounts available for disbursement. The loan under the RP OM Loan Agreement matures on the 10 year anniversary of the funding date and is repayable in quarterly installments, the amounts of which will depend on the occurrence of certain events related to the results and timing of COMET-HF and potential regulatory approvals of omecamtiv mecarbil, as follows: •Scenario 1: If the Phase 3 clinical trial of Cytokinetics’ proprietary small molecule cardiac myosin activator known as omecamtiv mecarbil is successful (defined as meeting the composite primary endpoint of the first event, whichever occurs first, comprising of cardiovascular death, heart failure event, LVAD implementation/cardiac transplantation, or stroke, with a hazard ratio (HR) of less than 0.85 and cardiovascular death endpoint HR of less than 1.0) by June 30, 2028 and we receive the marketing approval from the FDA for omecamtiv mecarbil on or prior to December 31, 2029 (“OM Approval Date”), commencing on the calendar quarter during which the FDA approval is obtained, we are required to pay RPDF (x) (i) $75.0 million ten business days after the OM Approval Date and (ii) $25.0 million on the first anniversary of the OM Approval Date and (y) on a quarterly basis an amount equal to 2.0% of the annual worldwide net sales of omecamtiv mecarbil, subject to a minimum floor amount ranging from $5.0 million to $8.0 million during the first 18 calendar quarters (the payment of the 2.0% of the annual worldwide net sales starting from the 19th calendar quarter shall be referred to as the “Royalty Payment”). Our obligation to pay the Royalty Payment will continue after maturity of the Loan; 33 Table of Contents •Scenario 2: If the Phase 3 clinical trial of omecamtiv mecarbil is successful by June 30, 2028 but we have not received the marketing approval from the FDA for omecamtiv mecarbil on or prior to December 31, 2029, we are required to pay RPDF 18 equal quarterly cash payments totaling 237.5% of the principal amount of the loan commencing on March 31, 2030; and •Scenario 3: If the Phase 3 clinical trial of omecamtiv mecarbil is not successful by June 30, 2028, we are required to pay RPDF 22 equal quarterly cash payments totaling 227.5% of the principal amount of the loan commencing on September 30, 2028. The interest on this loan is included in the scheduled payment amount for each scenario. Pursuant to the RP Ulacamten RPA, RPI ICAV purchased rights to up to 4.5% of worldwide net sales of drug products containing ulacamten by us, our affiliates or licensees, in exchange for up to $200 million in consideration, $50 million of which was paid upfront and, following the initiation of the first Phase 3 clinical trial (or the Phase 3 portion of the first Phase 2b/3 clinical trial) in HFpEF for ulacamten, at RPI ICAV’s sole discretion, up to in aggregate $150 million to fund 50.0% of the research and development cost of ulacamten. The initial $50 million paid to us entitles RPI ICAV to 1% of worldwide net sales of drug products containing ulacamten by us, our affiliates, or licenses. We will not know for certain whether any additional funding under the RP Ulacamten RPA may be available to us until the conclusion of AMBER-HFpEF, the results of the trial are known, and RPI ICAV has decided to exercise its option to purchase an incremental 3.5% revenue interest on our future annual worldwide net sales of drug products containing ulacamten or not. 2022 Royalty Pharma Transactions In January 2022, we entered into a series of financing agreements with affiliates of Royalty Pharma, including the RP Multi Tranche Loan Agreement, and the RP Aficamten RPA. Under the RP Multi Tranche Loan Agreement, we have drawn $275 million as of June 30, 2026. The remaining $175 million tranche 7 loan is also available to us now that the conditions for reimbursement, namely approval of our NDA for aficamten in patients with oHCM on or prior to December 31, 2025, have been met. We expect to draw Tranche 7 unless we are able to meet our financing requirements through more favorable funding sources. Each term loan under the RP Multi Tranche Loan Agreement matures on the 10 year anniversary of the funding date for such term loan and is repayable in quarterly installments of principal, interest and fees commencing on the last business day of the seventh full calendar quarter following the calendar quarter of the applicable funding date for such term loan, with the aggregate amount payable in respect of each term loan (including interest and other applicable fees) equal to 190% of the principal amount of the tranche 1, tranche 4, tranche 5, tranche 6, and tranche 7 term loans (such amount with respect to each term loan, “Final Payment Amount”). We commenced repayment of the RP Multi Tranche Loans in the fourth quarter of 2023 and will pay approximately $20.2 million in interest and principal on the term loans in 2026. RP Aficamten Royalty Purchase Agreement Under the RP Aficamten RPA, RPI ICAV purchased rights to certain revenue streams from net sales of pharmaceutical products containing aficamten by us, our affiliates and our licensees in exchange for up to $150.0 million in consideration, $50.0 million of which was paid on the closing date, $50.0 million of which was paid to us in March 2022 following the initiation of the first pivotal trial in oHCM for aficamten, and $50.0 million of which was paid to us in September 2023 following the initiation of the first pivotal clinical trial in nHCM for aficamten. RPI ICAV initially purchased the right to receive a percentage of net sales equal to 4.5% for annual worldwide net sales of pharmaceutical products containing aficamten up to $1 billion and 3.5% for annual worldwide net sales of pharmaceutical products containing aficamten in excess of $1 billion, subject to reduction in certain circumstances. However, in May 2024, we entered into the RP Aficamten RPA Amendment to restructure the royalty so that RPI will now receive 4.5% up to $5.0 billion of worldwide annual net sales of aficamten and 1% above $5.0 billion of worldwide annual net sales. Our liability to RPI ICAV is referred to as the “RP Aficamten Liability”. We account for the RP Aficamten Liability as a liability primarily because we have significant continuing involvement in generating the related revenue stream from which the liability will be repaid. When aficamten is commercialized and royalties become due, we will recognize the portion of royalties paid to RPI ICAV as a decrease to the RP Aficamten Liability and a corresponding reduction in cash. The carrying amount of the RP Aficamten Liability is based on our estimate of the future royalties to be paid to RPI ICAV over the life of the arrangement as discounted using an imputed rate of interest. The imputed rate of interest on the carrying value of the RP Aficamten Liability was approximately 26.1% as of June 30, 2026 and 20.5% as of June 30, 2025. 34 Table of Contents Convertible Notes On November 13, 2019, we issued $138.0 million aggregate principal amount of 2026 Notes. On July 6, 2022, we issued $540.0 million aggregate principal amount of 2027 Notes and used approximately $140.3 million of the net proceeds from the offering of 2027 Notes and issued 8,071,343 shares of common stock to repurchase approximately $116.9 million aggregate principal amount of the 2026 Notes pursuant to privately negotiated exchange agreements entered into with certain holders of the 2026 Notes concurrently with the pricing of the offering of the 2027 Notes. As a result of the partial repurchase of the 2026 Notes, we recorded a debt conversion expense of $22.2 million, consisting of the difference between the consideration to the holders pursuant to the exchange agreements and the if-converted value of the 2026 Notes under the original terms. On September 19, 2025, we issued $750.0 million aggregate principal amount of 2031 Notes and used approximately $402.5 million of the net proceeds from the offering of 2031 Notes and issued 2,168,806 shares of common stock to repurchase approximately $399.5 million aggregate principal amount of the 2027 Notes pursuant to privately negotiated exchange agreements entered into with certain holders of the 2027 Notes concurrently with the pricing of the offering of the 2031 Notes. This resulted in recording debt conversion expense in the third quarter of 2025 of $121.2 million, consisting of the difference between the consideration to the holders pursuant to the exchange agreements and the if-converted value of the 2027 Notes under the original terms. During the three months ended June 30, 2026, holders converted the remaining $21.1 million aggregate principal amount of the 2026 Notes into 2,002,817 shares of our common stock, together with an immaterial amount of cash paid in lieu of fractional shares. The conversions were completed in accordance with the original conversion terms of the 2026 Notes, and no gain or loss was recognized. As a result, the 2026 Notes were fully converted and no principal amount of 2026 Notes remained outstanding as of June 30, 2026. As of June 30, 2026, there remains $140.5 million of aggregate principal amount of 2027 Notes outstanding reflected in long term liabilities, and $750.0 million of aggregate principal amount of 2031 Notes outstanding in long term liabilities. The 2027 Notes are redeemable, in whole or in part (subject to the Partial Redemption Limitation, in the case of the 2027 Notes), at our option at any time, and from time to time, and, in the case of any partial redemption, on or before the 60th scheduled trading day before the applicable maturity date, at a cash redemption price equal to the principal amount of the relevant Convertible Notes to be redeemed, plus accrued and unpaid interest, if any, to, but excluding, the redemption date but only if the last reported sale price per share of our common stock exceeds 130% of the conversion price for the relevant notes on (1) each of at least 20 trading days, whether or not consecutive, during the 30 consecutive trading days ending on, and including, the trading day immediately before the date we may send the related redemption notice; and (2) the trading day immediately before the date we may send such notice. On or after October 6, 2028, the 2031 Notes will be redeemable, in whole or in part (subject to the Partial Redemption Limitation), at our option at any time and from time to time, and, in the case of any partial redemption, on or before the 40th scheduled trading day before the maturity date for the 2031 Notes, at a cash redemption price equal to the principal amount of the 2031 Notes to be redeemed, plus accrued and unpaid interest, if any, to, but excluding, the redemption date but only if the 2031 Notes are also freely tradable and all accrued and unpaid additional interest, if any, has been paid in full, as of the first interest payment date occurring on or before such redemption notice date, and the last reported sale price per share of our common stock exceeds 130% of the conversion price for the 2031 Notes on (1) each of at least 20 trading days, whether or not consecutive, during the 30 consecutive trading days ending on, and including, the trading day immediately before the date we may send the related redemption notice; and (2) the trading day immediately before the date we may send such notice. During the three months ended June 30, 2026, the conditions allowing holders of the 2027 Notes to convert were met. As a result, the 2027 Notes are convertible as of June 30, 2026. Greater China Out-license for Aficamten In July 2020, we entered into a license and collaboration agreement with Corxel, pursuant to which we granted to Corxel an exclusive license to develop and commercialize aficamten in China and Taiwan. In December 2024, Corxel assigned its rights and obligations under our license and collaboration agreement to Genzyme Corporation, an affiliate of Sanofi. In 2024, we recognized $15.0 million dollars from Corxel in connection with a modification of the original license prior to the assignment of Corxel's rights under our license and collaboration agreement for the development and commercialization of aficamten to Sanofi, and we may be eligible for another $10.0 million milestone payment from Corxel if certain conditions are met. In the fourth quarter of 2025, we recognized $15.0 million in aggregate milestone revenues from Sanofi upon approval of MYQORZO in each of the United States and China. We may be eligible to receive future milestone payments from Sanofi totaling up to $135.0 million for the achievement of certain development and commercial milestone events in connection to sales of MYQORZO and development of aficamten in nHCM. 35 Table of Contents In addition, Sanofi will pay us tiered royalties in the low-to-high teens range on the net sales of pharmaceutical products containing aficamten, including MYQORZO, in China and Taiwan, subject to certain reductions for generic competition, patent expiration and payments for licenses to third party patents. Sales to patients commenced in the first quarter of 2026. The Sanofi Aficamten License Agreement, unless terminated earlier, will continue on a market-by-market basis until expiration of the relevant royalty term. We expect royalty revenues in 2026 to be immaterial as Sanofi begins initial commercialization activities in China. Japan Out-license for Aficamten In November 2024, we entered into a license and collaboration agreement with Bayer Consumer Care AG, an affiliate of Bayer AG, pursuant to which we granted to Bayer an exclusive license to develop and commercialize aficamten in Japan, subject to certain reserved development rights. Under the terms of the Bayer License Agreement, we received an up-front payment of €50.0 million (equivalent to $52.4 million at the time of payment) which was recorded as deferred revenue at December 31, 2024 and was recognized in 2025 upon completion of certain performance technology transfer obligations. We recognized revenue associated with two clinical milestones totaling €10 million in 2025. We recognized an additional €10 million milestone in the first quarter of 2026 as a result of our first commercial sale of MYQORZO in the United States. We may also be eligible to receive up to an additional €70 million in milestones upon first commercial sale of aficamten in each of oHCM and nHCM in Japan and nHCM in the United States. We are also eligible for an additional €490 million in commercial milestone payments upon the achievement by Bayer of certain sales milestones and tiered royalties on the net sales of pharmaceutical products containing aficamten in Japan ranging from the high teens to the low thirty percents, subject to certain reductions for generic competition, expiration of certain patents and payments for licenses to third-party patents, until the latest of the expiration of certain patents, the expiration of regulatory exclusivity for the Product in Japan, and the end of a minimum specified term. At-the-Market Sales of Common Stock On February 27, 2025, we entered into an Open Market Sale AgreementSM with Jefferies LLC under which we may offer and sell, from time to time, at our sole discretion, shares of Common Stock in “at the market offerings” pursuant to Rule 415(a)(4) under the Securities Act of 1933 through Jefferies LLC, as sales agent. As of June 30, 2026, we have not sold any shares of Common Stock under the Open Market Sale AgreementSM with Jefferies LLC. Future Uses of Cash We expect that selling, general and administrative expenses will significantly increase in 2026. In December 2025, MYQORZO was approved by the FDA, and accordingly, our sales and marketing expenses will increase significantly as we engage in commercialization activities in the United States. In February 2026, the European Commission approved MYQORZO® (aficamten), 5 mg, 10 mg, 15 mg and 20 mg tablets for the treatment of symptomatic (NYHA class II-III) obstructive hypertrophic cardiomyopathy in adult patients, which means that we will significantly increase commercial readiness activities in Europe, initially in Germany, with commercial readiness activities in other major European countries to follow. In future periods, we also expect to incur substantial costs as we expand our research programs and continue development activities, including for the conduct of our on-going clinical trials for aficamten, omecamtiv mecarbil, ulacamten and CK-089. We expect to incur significant research and development expenses as we advance the research and development of compounds from our other muscle biology programs through research to candidate selection to clinical development, and we expect to file investigational new drug applications. Cytokinetics and multiple third-party contract development manufacturing organizations entered into various scopes of work with respect to the manufacturing of aficamten. As of June 30, 2026, we have approximately $18.6 million of non-cancellable commitments related to purchases of materials and inventory manufacturing agreements. Our future capital uses and requirements depend on numerous factors. These factors include, but are not limited to, the following: •the initiation, progress, timing, scope and completion of preclinical research, non-clinical development, CMC, and clinical trials for our drug candidates and other compounds; •the time, costs and outcomes of regulatory reviews or other regulatory actions related to our drugs and drug candidates, •the jurisdictions in which we are granted regulatory approvals and thus are able to successfully launch our products for commercial sale; •delays that may be caused by requirements of regulatory agencies; •our level of funding for the development of current or future drugs and drug candidates; •the number of drug candidates we pursue and the stage of development that they are in; •the costs involved in filing and prosecuting patent applications and attacking, enforcing or defending patent claims; 36 Table of Contents •our ability to establish and maintain selected strategic alliances required for the development of drug candidates and commercialization of our drugs and future drugs, if any; •our plans or ability to expand our drug development capabilities, including our capabilities to conduct clinical trials for our drug candidates; •our plans or ability to engage third-party manufacturers for our drugs or drug candidates; •our plans or ability to build or access sales and marketing capabilities, including commercial infrastructure and distribution capabilities, and to achieve market acceptance for MYQORZO and potential future drugs; •the expansion and advancement of our research programs; •the hiring of additional employees and consultants; •the acquisition of technologies, products and other business opportunities that require financial commitments; •our revenues from commercialization of MYQORZO and successful development and commercialization of any other drug candidates; •the cost of additional construction to expand our headquarters in South San Francisco and the cost in relation to expanding our leased office facilities in Radnor, Pennsylvania or other leased office spaces in Europe; and •the payments due for interest on the term loan and convertible debt; We have incurred an accumulated deficit of approximately $3.9 billion since inception and there can be no assurance that we will attain profitability. Although we have one approved product at this time, we remain subject to risks common to clinical-stage companies including, but not limited to, development of new drug candidates, dependence on key personnel, and the ability to obtain additional capital as needed to fund our future plans. Our liquidity will be impaired if sufficient additional capital is not available on terms acceptable to us, if at all. Until we achieve profitable operations, we intend to continue to fund operations through payments from strategic collaborations, additional sales of equity securities, grants and other financings. With the recent FDA approval of MYQORZO in December 2025, we have only recently started generating revenues from the commercial sale of our drugs. Therefore, our success is dependent on our ability to generate substantial revenues from MYQORZO or potentially obtain additional capital by entering into new strategic collaborations and/or through financings, and ultimately on our and our collaborators’ ability to successfully develop and market one or more of our drug candidates. We cannot be certain that sufficient funds will be available from such collaborators or financings when needed or on satisfactory terms, including as a result of economic conditions, general global economic uncertainty, political change, war, the effects of inflationary pressures, including those resulting from tariffs and escalating trade tensions, and other factors including past and potential future bank failures in the United States. Additionally, there can be no assurance that MYQORZO or any of our drug candidates will be accepted in the marketplace or that any future products can be developed or manufactured at an acceptable cost. These factors could have a material adverse effect on our future financial results, financial position and cash flows. Based on the current planning assumptions, we believe that our existing cash and cash equivalents, investments and interest earned on investments will be sufficient to meet our projected operating requirements for at least the next 12 months. If, at any time, our prospects for internally financing programs and activities decline, we may decide to reduce expenses across the business. Alternatively, we may raise funds through strategic relationships, public or private financings or other arrangements. There can be no assurance that funding, if needed, will be available on attractive terms, or at all, or in accordance with our planned timelines. Furthermore, financing obtained through future strategic relationships may require us to forego certain commercialization and other rights to our drug candidates. Similarly, any additional equity financing may be dilutive to stockholders and debt financing, if available, may involve restrictive covenants. Our failure to raise capital as and when needed could have a negative impact on our financial condition and our ability to pursue our business strategy. Segment Information We have one primary business activity and operate in one reportable segment. Critical Accounting Policies and Significant Estimates The accounting policies that we consider to be our most critical (i.e., those that are most important to the portrayal of our financial condition and results of operations and that require our most difficult, subjective or complex judgments), the effects of those accounting policies applied and the judgments made in their application are summarized in “Item 7 — Management’s Discussion and Analysis of Financial Condition and Results of Operations — Critical Accounting Policies and Significant Estimates” in our Annual Report on Form 10-K for the fiscal year ended December 31, 2025. There have been no material changes to our critical accounting policies and significant estimates in the six months ended June 30, 2026 , except for the following: 37 Table of Contents Net Product Revenue We recognize revenue from product sales at a point in time when our customer is deemed to have obtained control of the product, which generally occurs upon receipt or acceptance by our customer. In order to determine the transaction price, we estimate, utilizing the expected value method, the amount of variable consideration to which we will be entitled. Our product sales are subject to various deductions, including distribution-related fees, rebates under government programs, rebates for commercial payors, and amounts under our co-pay assistance program. The distribution-related fees include a prompt pay discount and fees for specialty pharmaceutical and specialty distributor customers. The distribution-related fees are not subject to significant estimation uncertainty. However, other sales deductions require us to make estimates, particularly related to the payor mix. We estimate the percentage of product sales which will ultimately be subject to commercial payor rebates, the Medicare Part D Manufacturer Rebate Program, Medicaid, and other federal programs. We also estimate the percentage of product sales which will ultimately go to 340B hospitals. As we have limited history for the sales of MYQORZO, we estimated our payor mix based upon our market research and industry data for similar cardiovascular products. As we gain more historical experience for the sales of MYQORZO, we will update our estimates which will result in adjustments to current period revenues. Inventories Inventories, which consist of raw materials, work in process and finished goods, are stated at the lower of cost or estimated net realizable value, using standard costs, based on a first-in, first-out method. We have entered into manufacturing and supply agreements for the manufacture or purchase of raw materials and production supplies in prior years. Our inventories include the direct purchase cost of materials and supplies, charges from contract manufacturing organizations and manufacturing overhead costs. We will periodically review our inventories for factors that could impact the future recoverability and realization of future sales, which require estimates and judgments. We will analyze our inventory levels quarterly and write down inventories subject to expiry, in excess of expected requirements or that has a cost basis in excess of its expected net realizable value. These write downs will be charged to cost of goods sold in the accompanying consolidated statements of operations and comprehensive loss. We received FDA approval for MYQORZO on December 19, 2025 and began capitalizing inventories upon FDA approval. Costs incurred prior to approval have been recorded as research and development expense in our consolidated statement of operations and comprehensive loss. As a result, inventory balances and cost of goods sold for the next several quarters are expected to reflect a lower average per unit cost of materials.