ITEM 1A. RISK FACTORS

In evaluating our business, you should carefully consider the following risks in addition to the other information in this report. Any of the following risks could materially and adversely affect our business, results of operations, financial condition, cash flows, reputation or your investment in our securities, and many are beyond our control. The risks and uncertainties described below are not the only ones facing us. Additional risks and uncertainties not presently known to us, or that we currently see as immaterial, may also adversely affect our business. The disclosures in this section reflect our beliefs and opinions as to factors that could materially and adversely affect us in the future. References to past events are provided by way of example only and are not intended to be a complete listing or a representation as to whether or not such factors have occurred in the past. The information discussed below should be considered carefully with the other information contained in this Annual Report on Form 10-K and the other documents and materials we file with the SEC, as well as news releases and other information we publicly disseminate from time to time.

Risks Specific to our Company in connection with our Commercial Operations

If physicians and patients do not accept our drugs, we may be unable to generate significant revenue, if any.

MYQORZO may not gain market acceptance among physicians, healthcare payors, patients and the medical community, and our other drug candidates, if approved, may similarly fail to gain market acceptance. Even if the clinical safety and efficacy of drugs developed from our drug candidates are established for purposes of approval, physicians may elect not to recommend these drugs for a variety of reasons including, but not limited to the availability of competitive drugs to the market, cost-effectiveness, availability of insurance coverage and reimbursement, convenience and ease of administration, prevalence and severity of adverse events, HCP practice patterns and familiarity with earlier to market therapies.

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The size of the potential market for MYQORZO or our product candidates is difficult to estimate and, if any of our assumptions are inaccurate, the actual markets for our products or product candidates may be smaller than our estimates. If the market opportunities for any products or product candidates we develop are smaller than we believe they are, or if any approval that we obtain is based on a narrower definition of the patient population, our potential revenues may be adversely affected, and our business may suffer.

Our potential market opportunity for oHCM, nHCM, and other indications is based on internal and third-party estimates and resources, including, without limitation, our estimates and research, as well as industry and general publications and research, surveys and studies conducted by Cytokinetics and third parties, which may be incorrect. Our estimated potential market opportunity for cardiac myosin inhibitors in oHCM and nHCM is based on the following assumptions: our understanding of the prevalence of HCM in the general population from published epidemiological studies and analysis of longitudinal claims data, the percentage split of diagnosed oHCM and nHCM patients derived from publications, market research and patient transaction databases, the percentage of available symptomatic patients not adequately managed by the current standard of care among diagnosed HCM patients, rates of patient compliance and persistence, based on patient transaction database and/or third-party market research. The conditions supporting our assumptions or estimates and the market data supporting these assumptions and estimates may change at any time or otherwise be inaccurate, thereby reducing the predictive accuracy of these underlying factors.

Our total addressable market will ultimately depend upon, among other things, the willingness of patients and HCPs to utilize MYQORZO compared to other cardiac sarcomere inhibitors or other therapies, the number of actual treatable symptomatic patients on MYQORZO and other cardiac myosin inhibitors or other therapies over time, the subset of eligible HCM patients who may utilize MYQORZO, acceptance and accessibility of our drug products by the medical community and patients, market share, drug pricing and reimbursement across payer types (i.e., Medicare, commercial, Medicaid, etc.). The number of patients within the United States and other major markets and elsewhere may turn out to be materially lower than expected, patients may not be otherwise amenable to treatment with our drugs or new patients may become increasingly difficult to identify or gain access to, all of which would harm our results of operations and our business. If our conclusions, analysis or internally generated data prove to be inaccurate or we make errors in our assumptions based on that data, our total addressable market may be meaningfully smaller than we have estimated, our future growth opportunities and sales growth may be impaired, any of which could have a material adverse effect on our business, financial condition and results of operations.

Our competitors may develop drugs that are less expensive, safer and/or have similar or better efficacy than ours, which may diminish or eliminate the commercial success of any drugs that we may commercialize.

We compete with companies that have developed drugs or are developing drug candidates for cardiovascular diseases, diseases and conditions associated with muscle weakness or wasting and other diseases for which our drug candidates may be useful treatments. We also compete for market share against large pharmaceutical and biotechnology companies and smaller companies that are collaborating with larger pharmaceutical companies, new companies, academic institutions, government agencies and other public and private research organizations. Many of these competitors, either alone or together with their partners, develop new drug candidates that can compete with ours. Many of these competitors have larger research and development programs or substantially greater financial resources than we do. If our competitors market drugs that are less expensive, safer and/or have similar or better efficacy than MYQORZO, or any other drugs that we may commercialize in the future, or that reach the market sooner than MYQORZO, or any other drugs that we may commercialize in the future, we may not achieve commercial success.

The commercial success of our products depends on the availability and sufficiency of third‐party payor and/or government for coverage and reimbursement.

Patients in the United States and elsewhere generally rely on third‐party payors and/or governments to reimburse part or all of the costs associated with their prescription drugs. Accordingly, market acceptance of our products is dependent on the extent to which third‐party coverage and reimbursement is available from government health administration authorities (including in connection with government healthcare programs, such as Medicare and Medicaid in the United States), private healthcare insurers and other healthcare funding organizations. Significant uncertainty exists as to the coverage and reimbursement status of any products for which we may obtain regulatory approval. Even if we obtain coverage for a given drug product, the timeframe from approval to coverage could be lengthy, inadequate, and/or the associated reimbursement rate may not be adequate to cover our costs, including research, development, intellectual property, manufacture, sale and distribution expenses, or may require co‐payments that patients find unacceptably high.

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We historically have had limited interactions and relationships with payors. Our ability to engage with US payors and secure coverage may improve as we commercialize MYQORZO and generate additional clinical and real-world evidence. Over time, we anticipate our drugs will be adopted by our patients as indicated by their labels. To achieve this adoption, our drugs will need to be widely reimbursed via medical exception or listed in formularies of major pharmacy benefit managers and payors in the U.S. These major pharmacy benefit managers and payors include Medicare, Medicaid, VA, DoD, TriCare, and commercial payors. The process to achieve coverage with pharmacy benefit managers and payors can be time consuming, is not guaranteed and if achieved can impact profitability given the level of rebates often required.

Coverage and reimbursement policies for drug products can differ significantly from payor to payor as there is no uniform policy of coverage and reimbursement for drug products among third‐party payors in the United States. There may be significant delays in obtaining coverage and reimbursement as the process of determining coverage and reimbursement is often time‐consuming and costly which will require us to provide scientific and clinical support for the use of our products to each payor separately, with no assurance that coverage or adequate reimbursement will be obtained. It is difficult to predict at this time what third parties will decide with respect to coverage and reimbursement for our products. Coverage policies and third-party reimbursement rates may change at any time. Even if favorable coverage and reimbursement status is attained for one or more products for which we receive regulatory approval, less favorable coverage policies and reimbursement rates may be implemented in the future.

In addition, there is significant uncertainty regarding the reimbursement status of newly approved healthcare products. We may need to conduct expensive pharmacoeconomic studies to demonstrate the cost-effectiveness of our products. If third-party payors do not consider our products to be cost-effective compared to other therapies, the payors may not cover our products as a benefit under their plans, or if they do, the level of payment may not be sufficient to allow us to sell our products on a profitable basis.

Additionally, to the extent required by regulatory authorities for the safe and effective use of any of our drug products, we or our partners may develop companion diagnostic tests for use with our products or product candidates such as with omecamtiv mecarbil. Companion diagnostic tests require coverage and reimbursement separate and apart from the coverage and reimbursement for their companion pharmaceutical or biological products. Similar challenges to obtaining coverage and reimbursement, applicable to pharmaceutical products, will apply to companion diagnostics and could adversely impact the commercial prospects of omecamtiv mecarbil or any other drug we may develop that requires a companion diagnostic test.

If we are unable to obtain and maintain sufficient third‐party coverage and adequate reimbursement for our products, the commercial success of MYQORZO, as well as any future marketed drug products may be greatly hindered and our financial condition and results of operations may be materially and adversely affected.

We have no manufacturing capabilities and depend on single source contract manufacturers to produce our commercial product and clinical trial materials, including our drug candidates, and will have continued reliance on contract manufacturers for the development and commercialization of our potential drugs.

We do not operate manufacturing facilities for clinical or commercial production of our drugs and drug candidates. We lack the resources and the capabilities to manufacture any of our drug candidates on a clinical or commercial scale.

In addition, under our license and collaboration agreements, we have committed to providing Sanofi and Bayer with supply of aficamten for development and commercialization of MYQORZO in China, Taiwan and Japan, which we will have to source from our contract manufacturers.

We currently rely on single source CMOs for the manufacture of any or all of MYQORZO as a finished drug product and the active pharmaceutical ingredient and registered starting materials used in the production of MYQORZO. We also rely on a single source CMO for the packaging of MYQORZO in blister packaging for use in Europe. If these CMOs fail to provide us with sufficient quantities of product or fail to comply with manufacturing regulations, our business could be harmed. Switching CMOs or manufacturing sites would be difficult and time-consuming because the number of potential CMOs is limited. In addition, before a drug from any replacement CMO or manufacturing site can be commercialized, the FDA and, in some cases, foreign regulatory agencies, must approve that site. These approvals would require regulatory testing and compliance inspections. A new CMO or manufacturing site also would have to be educated in, or develop substantially equivalent processes for, production of our drugs and drug candidates. It may be difficult or impossible to transfer certain elements of a manufacturing process to a new CMO or for us to find a replacement CMO on acceptable terms quickly, or at all, either of which would delay or prevent our ability to develop drug candidates and commercialize any resulting drugs.

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We also expect to rely on single source CMOs to supply all future drugs and drug candidates for which we conduct development, as well as other materials required to conduct our clinical trials, and to fulfil our obligations under our license and collaboration agreements. If our existing or future CMOs fail to, or are unable to perform satisfactorily or if any of the raw materials, drug substance, or drug products are subject to restrictive import/export controls or tariffs, it could impede commercialization or delay development or regulatory approval of our drug candidates or commercialization of our drugs, producing additional losses and depriving us of potential product revenues, and also lead to our breach of one of our license and collaboration agreements, giving rise to the ability to terminate such agreements and other adverse consequences as stipulated in such agreements. In addition, if a CMO fails to, or is unable to, perform as agreed, our ability to collect damages may be contractually limited.

Finally, the United States and other countries have imposed and may continue to impose new trade restrictions and export regulations, have levied tariffs and taxes on certain goods, including the potential for tariffs applicable to pharmaceutical products and their inputs. In September 2025, the United States administration announced plans to impose up to 100% tariffs on imported branded or patented pharmaceutical products, subject to certain exceptions. There is substantial uncertainty as to when such tariffs may go into effect and whether such tariffs would apply to the importation of registered starting materials, active pharmaceutical ingredients or bulk drug products that we use in our business, and, more generally, about the duration of existing tariffs, implementation of announced tariffs, litigation challenging tariffs and whether additional tariffs or other retaliatory measures may be imposed, modified or suspended. If additional tariffs, trade restrictions or other barriers are imposed or expanded, our costs for raw materials, active pharmaceutical ingredients, finished drug product or other inputs could increase materially, and our supply chain could be disrupted, which could materially adversely affect our business, financial condition and results of operations.

We may not be able to successfully manufacture our drugs or drug candidates in sufficient quality and quantity, which would delay or prevent us from developing our drug candidates and commercializing approved drug products.

Prior to the recent approval of MYQORZO in December 2025, our drug candidates had been manufactured in quantities adequate only for preclinical studies and early through late-stage clinical trials. In order to conduct large scale clinical trials for a drug candidate and for commercialization of the resulting drug if that drug candidate is approved for sale, such as for MYQORZO, we need to manufacture drugs in larger quantities and validate the repeatability of those manufacturing processes. We may not be able to successfully repeat or increase the manufacturing capacity for any of our drugs or drug candidates, in a timely or cost-effective manner or at all. Significant changes or scale-up of manufacturing may require additional validation studies, which are costly and which regulatory authorities must review and approve. In addition, quality issues may arise during those changes or scale-up activities because of the inherent properties of a drug or drug candidate itself or of a drug or drug candidate in combination with other components added during the manufacturing and packaging process, or during shipping and storage of the finished product or active pharmaceutical ingredients.

Our drug candidates and commercialized drugs, such as MYQORZO, require precise high-quality manufacturing. The failure to achieve and maintain high manufacturing standards in compliance with cGMP, including failure to document and detect, control, analyze and resolve anticipated or unanticipated manufacturing errors or the frequent occurrence of such errors, could result in patient injury or death, discontinuance or delay of ongoing or planned clinical trials, delays or failures in product testing or delivery or regulatory approval, cost overruns, product recalls or withdrawals and other problems that could seriously hurt our business. Contract drug manufacturers often encounter difficulties involving production yields, quality control and quality assurance and shortages of qualified personnel. These manufacturers are subject to stringent regulatory requirements, including cGMPs, regulations and similar foreign laws and standards. Each contract manufacturer must pass a pre-approval inspection before we can obtain marketing approval for any of our drug candidates and following approval will be subject to ongoing periodic unannounced inspections by the FDA, the U.S. Drug Enforcement Agency and other regulatory agencies, to ensure strict compliance with cGMPs and other applicable government regulations and corresponding foreign laws and standards. We seek, and require our contract manufacturers, to comply fully with all applicable regulations, laws and standards. However, we do not have control over our contract manufacturers’ compliance with these regulations, laws and standards. If one of our contract manufacturers fails to pass its pre-approval inspection or maintain ongoing compliance at any time, the production of our drugs or drug candidates could be interrupted, negatively impacting commercialization efforts for our approved drug products or resulting in delays or discontinuance of our clinical trials or refusal of regulatory approval for our drug candidates, leading to additional costs and potentially lost revenues. In addition, failure of any third-party manufacturers or us to comply with applicable regulations, including pre- or post-approval inspections and the cGMP requirements of the FDA or other comparable regulatory agencies, could result in sanctions being imposed on us. These sanctions could include fines, injunctions, civil penalties, failure of regulatory authorities to grant marketing approval of our products, delay, suspension or withdrawal of approvals, license revocation, product seizures or recalls, operational restrictions and criminal prosecutions, any of which could significantly and adversely affect our business.

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Approved drug products remain subject to ongoing obligations, including continued regulatory review by the FDA and foreign regulatory agencies and REMS, all of which may result in significant expense and limit commercialization efforts of our drugs.

Any regulatory approvals that we or our partners receive for our drugs or drug candidates are subject to limitations on the indicated uses for which the drug may be marketed or require potentially costly post-marketing follow-up studies or compliance with a REMS program that includes ETASU. For example, MYQORZO is subject to a comprehensive REMS program that includes, among other things, restrictions and qualifications on pharmacies that dispense the drug and certification, record-keeping, ongoing monitoring and patient counseling obligations on physicians who prescribe the drug. In addition, in connection with the approval of MYQORZO the FDA requires the conduct of the following post-marketing studies: (i) a worldwide descriptive study that collects prospective and retrospective data in women exposed to MYQORZO during pregnancy to assess risks of pregnancy and maternal complications, and adverse effects on the developing fetus, the neonate, and the infant, as well as to assess infant outcomes through at least the first year of life and (ii) a milk-only lactation study in lactating women who have received MYQORZO to measure concentrations of MYQORZO in breast milk using a validated assay, as well as to assess the effects on the breastfed infant, if available, based on study population.

In addition, the labeling, packaging, adverse event reporting, storage, advertising, promotion and record-keeping for approved drugs remain subject to extensive regulatory requirements. The subsequent discovery of previously unknown problems with a drug, including adverse events of unanticipated severity or frequency, or the discovery that adverse events or toxicities observed in preclinical research or clinical trials that were believed to be minor constitute much more serious problems, may result in restrictions on the marketing of the drug or withdrawal of the drug from the market.

If the FDA or comparable foreign regulatory authorities approve generic versions of MYQORZO, or any other potential products that receive marketing approval, or such authorities do not grant MYQORZO appropriate periods of data or market exclusivity before approving a generic version, sales of MYQORZO could be adversely affected.

Once an NDA is approved, the drug covered thereby becomes a “reference-listed drug” in the FDA’s publication, “Approved Drug Products with Therapeutic Equivalence Evaluations.” Manufacturers may seek marketing approval of generic versions of reference-listed drugs through submission of Abbreviated New Drug Applications (“ANDAs”) in the United States. Generic drugs may be significantly less costly to bring to market than the reference-listed drug and companies that produce generic drugs are generally able to offer them at lower prices. Thus, following the introduction of a generic drug, a significant percentage of the sales of any branded product or reference-listed drug is typically lost to the generic drug.

The FDA may not approve an ANDA or a 505(b)(2) NDA for a generic drug until any applicable period of non-patent exclusivity for the reference-listed drug has expired. The FDCA provides a period of five years of non-patent exclusivity for a new drug containing a new chemical entity. During the exclusivity period, the FDA may not accept for review an ANDA or a 505(b)(2) NDA submitted by another company for another version of such product candidate where the applicant does not own or have a legal right of reference to all the data required for approval. However, an application may be submitted after four years if it contains a certification of patent invalidity or non-infringement. The FDCA also provides three years of marketing exclusivity for an NDA, 505(b)(2) NDA or supplement to an approved NDA if new clinical investigations, other than bioavailability studies, that were conducted or sponsored by the applicant are deemed by the FDA to be essential to the approval of the application, for example, for new indications, dosages or strengths of an existing product candidate. This three-year exclusivity covers only the conditions associated with the new clinical investigations and does not prohibit the FDA from approving ANDAs for product candidates containing the original active agent for other conditions of use. Five-year and three-year exclusivity will not delay the submission or approval of a full NDA. However, an applicant submitting a full NDA would be required to conduct or obtain a right of reference to all of the nonclinical studies and adequate and well-controlled clinical trials necessary to demonstrate safety and effectiveness. Manufacturers may seek to launch generic drugs following the expiration of the marketing exclusivity period, even if we still have patent protection for such drugs.

Competition that MYQORZO, or any other potential product candidates, may face from generic drugs could materially and adversely impact our future revenue, profitability and cash flows and substantially limit our ability to obtain a return on the investments we have made in those products. Our future revenues, profitability and cash flows could also be materially and adversely affected and our ability to obtain a return on the investments we have made in MYQORZO or other product candidates may be substantially limited if MYQORZO, or any other potential products, product candidates, are not afforded the appropriate periods of non-patent exclusivity.

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Risks Specific to our Company in connection with our Research and Development Activities

The regulatory approval and marketing authorization process is expensive, time-consuming and uncertain and may prevent our partners or us from obtaining approvals to commercialize some or all of our drug candidates.

The research, testing, manufacturing, selling and marketing of drugs are subject to extensive regulation by the FDA and other regulatory authorities in the United States and other countries. Neither we nor our partners are permitted to market our potential drugs in the United States until we receive approval of an NDA from the FDA. Obtaining NDA approval is a lengthy, expensive and uncertain process. The FDA and foreign regulatory agencies can delay, limit or deny approval of a drug candidate for many reasons, including, but not limited to, a determination that a drug candidate is not safe or effective, that the data from non-clinical testing and clinical trials is insufficient and that our partner’s or the contract manufacturer’s processes or facilities are not in compliance with GMP. Even if we receive regulatory approval to manufacture and sell a drug in a particular regulatory jurisdiction, other jurisdictions’ regulatory authorities may not approve that drug for manufacture and sale.

Regulatory approval of an NDA, NDA supplement or other marketing application for our drug candidates is never guaranteed. For example, our NDA for omecamtiv mecarbil for the treatment of HFrEF resulted in a complete response letter notwithstanding the fact that GALACTIC-HF met its primary efficacy endpoint. As our previously filed NDA for omecamtiv mecarbil illustrates, while we may submit marketing authorization applications for our drug candidates in the future, such applications may not lead to any regulatory approvals, or may result in requirements to conduct additional clinical trials prior to any potential approvals, which would increase our development costs and delay or preclude any revenue from commercial sales of our drug candidates.

Disruptions at the FDA, including due to a reduction in the FDA’s workforce and/or inadequate funding for the FDA, could prevent the FDA from performing normal functions on which our business relies, which could negatively impact our business.

The ability of the FDA to review and approve new products or review other regulatory submissions can be affected by a variety of factors, including statutory, regulatory and policy changes, inadequate government budget and funding levels, a reduction in the FDA’s workforce and its ability to hire and retain key personnel. Disruptions at the FDA and other agencies may also increase the time to meet with and receive agency feedback, review and/or approve our submissions, conduct inspections, issue regulatory guidance, or take other actions that facilitate the development, approval and marketing of regulated products, which would adversely affect our business. For example, over the last several years the U.S. government has shut down several times and certain regulatory agencies, such as the FDA, have had to furlough critical employees and stop critical activities. Most recently, during the U.S. government shut down in October 2025, the FDA was not able to accept applications for new drugs, generics, biologics, biosimilars or medical devices that require payment of a user fee. In addition, government proposals to reduce or eliminate budgetary deficits may include reduced allocations to the FDA and other related government agencies. For example, the current United States administration established the now-disbanded Department of Government Efficiency, which implemented a federal government hiring freeze and announced certain additional efforts to reduce federal government employee headcount, including by eliminating 3,500 employees from the FDA, and the size of the federal government. The reductions in the FDA’s workforce and budgetary pressures could significantly impact the ability of the FDA to timely review and process our regulatory submissions or take other actions critical to the marketing of any of our product candidates that are ultimately approved. Any delay in the acceptance, review or approval of our investigational new drug applications, clinical trial applications, marketing applications, facility inspections or lot-release/testing activities could delay or increase the cost of our clinical trials, manufacturing scale-up, product launches or post-approval changes, which could have a material adverse effect on our business.

Clinical trials could fail to demonstrate the desired safety and efficacy of our drug candidates, which could prevent or significantly delay completion of clinical development and regulatory approval.

Prior to receiving approval to commercialize any of our drug candidates, we or our partners must adequately demonstrate to the satisfaction of FDA and foreign regulatory authorities that the drug candidate is sufficiently safe and effective with substantial evidence from well-controlled clinical trials. We or our partners must demonstrate efficacy in clinical trials for the treatment of specific indications and monitor safety throughout the clinical development process and following approval. Although our NDA for MYQORZO was approved in December 2025, we have failed in the past to meet the burdens for efficacy and safety required by FDA and other regulatory authorities. For example, the CRL we received in February 2023 in connection with our NDA for omecamtiv mecarbil stated that the results of GALACTIC-HF were not sufficiently persuasive to establish substantial evidence of effectiveness for reducing the risk of heart failure events and cardiovascular death in adults with chronic heart failure with HFrEF, and in March 2023, we announced the discontinuation of COURAGE-ALS, our Phase 3 clinical trial of reldesemtiv in patients with ALS, due to futility. If we fail to demonstrate that our drugs are safe and efficacious, we may incur additional development costs and be precluded from realizing commercial sales for our drug candidates.

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Drug candidates that have similar mechanisms of actions to ours have been subject to clinical trials that have failed to meet their primary endpoints. For example, Camzyos® (mavacamten), a small molecule myosin inhibitor commercialized by Bristol-Myers Squibb Company has a similar mechanism of action to aficamten and failed to meet its dual primary endpoints in ODYSSEY-HCM, a Phase 3 clinical trial assessing its efficacy for the treatment of nHCM. Although such result is not dispositive on the eventual results of our clinical trial of aficamten in nHCM, ACACIA-HCM, the results of ODYSSEY-HCM may suggest that a myosin inhibitor is not effective for the treatment of nHCM notwithstanding the positive results in clinical trials of such drugs in oHCM. In addition, the nHCM patient population presents distinct physiological differences from the oHCM population and those differences may require different dosing strategies to achieve a functional benefit, if at all. As compared to our oHCM trials, this difference in disease pathology and dosing strategy, among other things, could result in a different magnitude of functional benefit, if any, in ACACIA-HCM; it could also result in more treatment interruptions or it could alter the safety profile of aficamten observed in ACACIA-HCM. In the event such differences in functional benefit are observed, regulatory agencies may not approve the nHCM indication or such regulatory approvals may be delayed.

The regulatory pathway for approval also depends on the totality of clinical data and regulatory agencies’ interpretations of what constitutes a minimally important clinical difference in these functional endpoints, which can be subjective because there is no universally established standard. There are a wide range of possible outcomes (e.g., positive, negative or mixed) for the results of ACACIA-HCM, including that we do not demonstrate either a magnitude of functional benefit that regulators deem satisfactory for approval or a magnitude of functional benefit that physicians deem sufficient to prescribe MYQORZO for their patients. In such cases, regulatory agencies may not approve the nHCM indication or may delay such approval, or physicians may not prescribe MYQORZO for their patients, respectively.

Our failure to demonstrate that our drugs are safe and efficacious can result in additional development costs and preclude us from realizing commercial sales for our drug candidates.

If we encounter difficulties enrolling patients in our clinical trials, our clinical development activities could be delayed or otherwise adversely affected.

The timely completion of clinical trials in accordance with their protocols depends, among other things, on our ability to enroll a sufficient number of patients who remain in the trial until its conclusion. We may experience difficulties in patient enrollment in clinical trials for a variety of reasons, including, but not limited to, the existence of approved therapies and the concurrent enrollment of clinical trials for competing therapies. The enrollment of patients depends on many factors, including: the patient eligibility criteria defined in the protocol; the size of the patient population required for analysis of the trial’s primary endpoints; the proximity of patients to study sites; the design of the trial; the ability to recruit clinical trial investigators with the appropriate competencies and experience; clinicians’ and patients’ perceptions as to the potential advantages of the product candidate being studied in relation to other available therapies or clinical trials being conducted by our competitors; the ability to obtain and maintain patient consents; the risk that patients enrolled in clinical trials will drop out of the trials before completion. Delays in patient enrollment may result in increased costs or may affect the timing or outcome of the planned clinical trials, which could prevent completion of these trials and adversely affect our and our partners’ ability to advance the development of product candidates.

The failure to successfully develop, manufacture and obtain regulatory clearance or approval of an immunoassay or companion diagnostics, if required by FDA as a condition to approval of our drugs, could harm our development and commercialization strategy for such drugs in key markets.

In connection with the anticipation of filing of a new NDA and MAA for omecamtiv mecarbil at the conclusion of COMET-HF, FDA and/or EMA may require that patients treated with omecamtiv mecarbil have their blood monitored during titration for concentrations of the drug in order to determine optimized dosing that maximizes benefits without undue risk. We have contracted with Microgenics Corporation, a subsidiary of Thermo Fisher, to develop and eventually commercialize an antibody-based immunoassay for blood concentrations of omecamtiv mecarbil. The development, manufacture and regulatory approval of an antibody-based immunoassay, however, can be complex and/or time consuming. Such an immunoassay could require regulatory clearance by FDA as a companion diagnostic device or similar regulatory clearance by EMA, and there is no assurance that such regulatory clearance will be obtained. In addition, if required by FDA and/or EMA as part of any approved label for omecamtiv mecarbil, we will be dependent on Microgenics Corporation to successfully manufacture and commercialize its immunoassay in sufficient quantities in all key markets in which we may seek to commercialize omecamtiv mecarbil, failing which, our potential sales of omecamtiv mecarbil could be materially adversely affected.

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We depend on CROs to conduct our clinical trials and we have limited control over their performance. If these CROs do not successfully carry out their contractual duties or meet expected deadlines, or if we lose any of our CROs, we may not be able to obtain regulatory approval for or commercialize our product candidates on a timely basis, if at all.

We have used and intend to continue to use a limited number of CROs within and outside of the United States to conduct clinical trials of our drug candidates and related activities. We do not have control over many aspects of our CROs’ activities, and cannot fully control the amount, timing or quality of resources that they devote to our programs. CROs may not assign as high a priority to our programs or pursue them as diligently as we would if we were undertaking these programs ourselves. The activities conducted by our CROs therefore may not be completed on schedule or in a satisfactory manner. CROs may also give higher priority to relationships with our competitors and potential competitors than to their relationships with us. Outside of the United States, we are particularly dependent on our CROs’ expertise in communicating with clinical trial sites and regulatory authorities and ensuring that our clinical trials and related activities and regulatory filings comply with applicable laws.

Although we rely, and will continue to rely, on these third parties to conduct our clinical trials, we remain responsible for our studies and clinical trials being conducted in accordance with the applicable protocol, legal, regulatory and scientific standards and our reliance on third parties does not relieve us of our regulatory responsibilities. We, and these third parties are required to comply with cGCPs for clinical studies. cGCPs are regulations and guidelines enforced by the FDA, EMA and comparable foreign regulatory authorities for all of our products in clinical development. Regulatory authorities enforce cGCPs through periodic inspections of trial sponsors, principal investigators and trial sites. If we or any of our third-party contractors fail to comply with applicable regulatory requirements, including cGCPs, the clinical data generated in our clinical trials may be deemed unreliable and FDA, EMA, or comparable foreign regulatory authorities may require us to perform additional clinical trials before approving our marketing applications. There can be no assurance that upon inspection by a given regulatory authority, such regulatory authority will determine that any of our clinical trials comply with cGCP regulations. In addition, our clinical trials must be conducted with product produced under cGMP regulations. Our failure to comply with these regulations may require us to repeat clinical trials, which could add additional costs and could delay the regulatory approval process.

Risks Specific to our Company in connection with our Intellectual Property

Our success depends substantially upon our ability to obtain and maintain intellectual property protection relating to our drug candidates, compounds and research technologies.

We own, co-own or hold exclusive licenses to a number of U.S. and foreign patents and patent applications directed to our drug candidates, compounds and research technologies. Our success depends on our ability to obtain patent protection both in the United States and in other countries for our drug candidates, their methods of manufacture and use, and our technologies. Our ability to protect our drugs and drug candidates, and compounds and technologies from unauthorized or infringing use by third parties depends substantially on our ability to obtain and enforce our patents. If our issued patents and patent applications, if granted, do not adequately describe, enable or otherwise provide coverage for our technologies and drugs and drug candidates, we, our licensors or our licensees would not be able to exclude others from developing or commercializing these drugs or drug candidates. Furthermore, the degree of future protection of our proprietary rights is uncertain because legal means may not adequately protect our rights or permit us to gain or keep our competitive advantage. If we are unable to obtain and maintain sufficient intellectual property protection for our technologies and drugs or drug candidates, or if the scope of the intellectual property protection obtained is not sufficiently broad, our competitors could develop and commercialize drugs similar or identical to ours, and our ability to successfully commercialize product candidates that we may pursue may be impaired.

We may not be able to protect our intellectual property rights throughout the world. Patent protection is afforded on a country-by-country basis. In addition, our patents in foreign jurisdictions may be subject to opposition proceedings that challenge the validity of our patents. For example, our composition of matter and a crystalline form patent for aficamten are subject to oppositions in the EU. If we were to lose these proceedings and suffer patent invalidity, our commercial prospects for aficamten in the EU may, absent the continued effectiveness of our other patents in the EU, including our composition of matter patent in the EU, be adversely affected. Moreover, we may not seek patent protection in all jurisdictions throughout the world. Filing, prosecuting and defending patents on our products or product candidates in all countries throughout the world would be prohibitively expensive, and our intellectual property rights in some countries outside the United States can be less extensive than those in the United States. Many companies have encountered significant difficulties in protecting and defending intellectual property rights in foreign jurisdictions. In addition, the legal protection afforded to inventors and owners of intellectual property in countries outside of the United States may not be as protective of intellectual property rights as in the United States. Therefore, we may be unable to acquire and protect intellectual property developed by these contractors to the same extent as if these development activities were being conducted in the United States. If we encounter difficulties in protecting our intellectual property rights in foreign jurisdictions, our business prospects could be substantially harmed.

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Patent terms may be inadequate to protect our competitive position on our technologies, drugs and drug candidates for an adequate amount of time. Patents have a limited lifespan. In the United States, if all maintenance fees are timely paid, the natural expiration of a patent is generally 20 years from its earliest U.S. non-provisional filing date. Various extensions may be available, but the life of a patent, and the protection it affords, is limited. Even if patents covering our technologies, drugs and drug candidates are obtained, once the patent life has expired, we may be open to competition from competitive products, including generics. Given the amount of time required for the development, testing and regulatory review of new drugs and drug candidates, patents protecting such candidates might expire before or shortly after such drugs or drug candidates are commercialized. As a result, our owned, co-owned and licensed patent portfolio may not provide us with sufficient rights to exclude others from commercializing products similar or identical to ours or our partners.

If we are unable to protect the confidentiality of our trade secrets, the value of our technology could be materially adversely affected and our business would be harmed, and we may be subject to claims that our employees, consultants or independent contractors have wrongfully used or disclosed confidential information of third parties or that we or our employees have wrongfully used or disclosed trade secrets of their former employers.

We rely on trade secrets to protect our technology, particularly where we believe patent protection is not appropriate or obtainable. However, trade secrets are often difficult to protect, especially outside of the United States. While we endeavor to use reasonable efforts to protect our trade secrets, our or our partners’ employees, consultants, contractors or scientific and other advisors may unintentionally or willfully disclose our information to competitors. In addition, confidentiality agreements, if any, executed by those individuals may not be enforceable or provide meaningful protection for our trade secrets or other proprietary information in the event of unauthorized use or disclosure. We cannot be certain that such agreements have been entered into with all relevant parties, and we cannot be certain that our trade secrets and other confidential proprietary information will not be disclosed or that competitors will not otherwise gain access to our trade secrets or independently develop substantially equivalent information and techniques. Pursuing a claim that a third party had illegally obtained and was using our trade secrets would be expensive and time-consuming, and the outcome would be unpredictable. Even if we are able to maintain our trade secrets as confidential, if our competitors lawfully obtain or independently develop information equivalent or similar to our trade secrets, our business could be harmed.

Additionally, many of our employees were previously employed at universities or other biotechnology or pharmaceutical companies, including our competitors or potential competitors. Although no legal proceedings against us are currently pending, we may be subject to claims that these employees or we have inadvertently or otherwise used or disclosed trade secrets or other proprietary information of their former employers. Litigation may be necessary to defend against these claims. If we fail in defending these claims, in addition to paying monetary damages, we may lose valuable intellectual property rights or personnel. A loss of key research personnel or their work product could hamper or prevent our ability to develop and commercialize certain potential drugs, which could significantly harm our business. Even if we are successful in defending against these claims, litigation could result in substantial costs and distract management.

Infringement lawsuits are costly and time-consuming, and an unfavorable outcome could have a significant adverse effect on our business, including our ability to market MYQORZO to the fullest extent permissible within regulatory approvals.

Our ability to commercialize drugs depends on our ability to use, manufacture and sell those drugs without infringing the patents or other proprietary rights of third parties. Numerous U.S. and foreign issued patents and pending patent applications owned by third parties exist in the therapeutic areas in which we are developing drug candidates or seeking new potential drug candidates, while others may exist that claim methods of use of our existing drugs. For example, we are aware of the existence of a patent application relating to cardiac myosin inhibitors for which a notice of allowance has been issued by the U.S. Patent and Trademark Office. Once a notice of allowance has been issued, there are typically no further substantive hurdles to patent issuance and the only remaining administrative step to be conducted by the assignee is the payment of the USPTO’s issue fee within the 3-month deadline to pay the issue fee. If a patent is issued with respect to this application, the patent holder may assert that patent claims cover certain aspects of treating patients with HCM. Such claims could result in patent litigation, injunctive relief and/or damages if we are found to be infringing.

In addition, third parties may infringe our patents. To prevent infringement or unauthorized use, we may need to file infringement suits, which are expensive and time-consuming. In an infringement proceeding, a court may decide that one or more of our patents is invalid, unenforceable, or both. In such case third parties may be able to use our technology without paying licensing fees or royalties. Even if the validity of our patents is upheld, a court may refuse to stop the other party from using the technology at issue on the ground that the other party’s activities are not covered by our patents. Policing unauthorized use of our intellectual property is difficult, and we may not be able to prevent misappropriation of our proprietary rights, particularly in countries where the laws may not protect such rights as fully as in the United States. In addition, third parties may affirmatively challenge the scope or validity of our patent rights.

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Financial Risks

We have a history of significant losses and may not achieve or sustain profitability and, as a result, you may lose part or all of your investment.

We have incurred operating losses in each year since our inception in 1997, due to costs incurred in connection with our research and development activities and general and administrative costs associated with our operations. We have only recently commenced commercialization activities with the approval of MYQORZO in December 2025. Our other drug candidates are all in early through late-stage clinical testing. We expect to incur losses, as we continue our research activities and conduct development of, and seek regulatory approvals for, our other drug candidates, and begin our commercialization efforts on MYQORZO. If our other drug candidates fail or do not gain regulatory approval, or if MYQORZO or our other drug candidates do not achieve market acceptance, we will not be profitable. If we fail to become and remain profitable, or if we are unable to fund our continuing losses, you could lose part or all of your investment.

We will need substantial additional capital in the future to sufficiently fund and maintain our operations.

We have consumed substantial amounts of capital to date, and our operating expenditures will increase as we expand our research and development activities and expand our organization to commercialize MYQORZO. We have historically funded our operations and capital expenditures with proceeds primarily from private and public sales of our equity securities, royalty monetization agreements, revenue interest agreements, strategic alliances, long-term debt, other financings, interest on investments and grants but will be increasingly relying on revenues generated from the commercial sales of MYQORZO to fund our operations and cash expenditures. We believe our existing cash and cash equivalents, short-term investments and interest earned on investments should be sufficient to meet our projected operating requirements for at least the next 12 months. We based this estimate on assumptions that may prove to be wrong, and we could utilize our available capital resources sooner than we currently expect. Because of the numerous risks and uncertainties associated with the development of our drug candidates and other research and development activities, including risks and uncertainties that could impact the rate of progress of our development activities, we are unable to estimate with certainty the amounts of capital outlays and operating expenditures associated with these activities.

For the foreseeable future, our operations will require significant additional funding, in large part due to our research and development expenses, the organizational scale up and associated expenditures with the commercialization of MYQORZO, combined with the absence of any revenues until first quarter 2026. Until we can generate a sufficient amount of product revenue, we expect to raise future capital through strategic alliance and licensing arrangements, public or private equity offerings and debt financings. We do not have any commitments for future funding other than through loans under the RP Multi Tranche Loan Agreement and reimbursements, milestone and royalty payments that we may receive under our agreements with Sanofi and Bayer. We may not receive any further funds under any of these agreements, for example, if we fail to satisfy the conditions for future loan disbursement or as a result of the default or insolvency of our lenders. Our ability to raise funds may be adversely impacted by worsening economic conditions or disruptions to, and volatility in, the credit and financial markets in the U.S. and worldwide, including due to general economic uncertainty, geopolitical conditions, armed conflict and hostilities, interest rate volatility, inflationary pressures, including those resulting from tariffs and escalating trade tensions, and other factors outside of our control. As a result of these and other factors, we do not know whether additional financing will be available when needed, or that, if available, such financing would be on terms favorable to our stockholders or us, and if we cannot raise the funds we need to operate our business, we will need to delay or discontinue certain research and development activities, and our stock price may be negatively affected.

Our indebtedness and liabilities could limit the cash flow available for our operations, expose us to risks that could adversely affect our business, financial condition and results of operations and impair our ability to satisfy our obligations under the Convertible Notes, the RP Multi Tranche Loan Agreement and the RP OM Loan Agreement.

As of December 31, 2025 and 2024 we had $1.3 billion and $0.8 billion of debt recorded on the balance sheet comprised of the Term loans (including related derivative measured at fair value), Liabilities related to RPI Transactions measured at fair value, and the Convertible Notes, respectively. Additionally we have liabilities related to revenue participation right purchase agreements of $520.6 million and $462.2 million at December 31, 2025 and 2024, respectively.

We may also incur additional indebtedness to meet future financing needs. Our indebtedness could have significant negative consequences for our security holders and our business, results of operations and financial condition by, among other things: increasing our vulnerability to adverse economic and industry conditions; limiting our ability to obtain additional financing; requiring the dedication of a substantial portion of our cash flow from operations to service our indebtedness, which will reduce the amount of cash available for other purposes; limiting our flexibility to plan for, or react to, changes in our business; diluting the interests of our existing stockholders as a result of issuing shares of our common stock upon conversion of the Convertible Notes; and placing us at a possible competitive disadvantage with competitors that are less leveraged than us or have better access to capital.

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Our business may not generate sufficient funds, and we may otherwise be unable to maintain sufficient cash reserves, to pay amounts due under our indebtedness and our cash needs may increase in the future. In addition, any required repurchase of the Convertible Notes for cash as a result of a Fundamental Change would lower our current cash on hand such that we would not have those funds available for us in our business. Further any future indebtedness that we may incur may contain financial and other restrictive covenants that limit our ability to operate our business, raise capital or make payments under our other indebtedness. If we fail to comply with these covenants or to make payments under our indebtedness when due, then we would be in default under that indebtedness, which could, in turn, result in that and our other indebtedness becoming immediately payable in full.

Covenants in the RP Multi Tranche Loan Agreement, the RP OM Loan Agreement, the RP Ulacamten RPA, the RP Aficamten RPA, the RP OM RPA, and the indentures related to our Convertible Notes restrict our business and operations in many ways and if we do not effectively manage our covenants, our financial conditions and results of operations could be adversely affected.

The RP Multi Tranche Loan Agreement, the RP OM Loan Agreement, the RP Ulacamten RPA, the RP Aficamten RPA, the RP OM RPA, and the indentures related to the Convertible Notes require that we comply with certain covenants, including among other things, covenants restricting dispositions, changes in business, management, ownership or business locations, mergers or acquisitions, indebtedness, encumbrances, distributions, investments, transactions with affiliates and subordinated debt, any of which could restrict our business and operations, particularly our ability to respond to changes in our business or to take specified actions to take advantage of certain business opportunities that may be presented to us. In addition, the RP Ulacamten RPA, the RP Aficamten RPA and the RP OM RPA contain certain covenants applicable to us, including among other things, development and commercialization diligence obligations in connection to MYQORZO, omecamtiv mecarbil and ulacamten and reporting obligations, which could also restrict our business and operations, particularly in connection to our development and commercialization of MYQORZO, omecamtiv mecarbil and ulacamten.

Our failure to comply with any of the covenants could result in a default under the RP Multi Tranche Loan Agreement, the RP OM Loan Agreement, the RP Ulacamten RPA, the RP Aficamten RPA, the RP OM RPA, or the indentures related to the Convertible Notes, which could permit the counterparties to declare all or part of any outstanding borrowings or other payment obligations to be immediately due and payable and/or enforce any outstanding liens against our assets.

We have no rights to repurchase the revenue interests in drug products containing aficamten, omecamtiv mecarbil, or ulacamten (other than, in respect of ulacamten only, in connection with a change of control of Cytokinetics) sold to affiliates of Royalty Pharma, thereby limiting our ability to eliminate future applicability of the covenants contained in the RP Ulacamten RPA, the RP OM RPA and the RP Aficamten RPA, and although we have voluntary prepayment rights under the RP Multi Tranche Loan Agreement and the RP OM Loan Agreement, any voluntary prepayment rights under the RP Multi Tranche Loan Agreement require that we pay 190% of the principal amount of amounts disbursed to us as tranche 1, tranche 4, tranche 5, tranche 6, and tranche 7 loans, thereby making it potentially disadvantageous to voluntarily prepay RPDF prior to the final maturity date applicable to loans outstanding under the RP Multi Tranche Loan Agreement.

Finally, should we be unable to comply with our covenants or if we default on any portion of our outstanding borrowings under the RP Multi Tranche Loan Agreement or the RP OM Loan Agreement, in addition to its rights to accelerate and demand for immediate repayment of amounts outstanding under the RP Multi Tranche Loan Agreement, we would be liable for default interest at a rate of 4% over the prime rate.

Conversion of our outstanding Convertible Notes may result in the dilution of existing stockholders, create downward pressure on the price of our common stock, and restrict our ability to take advantage of future opportunities.

The Convertible Notes may be converted into cash and/or shares of our common stock (subject to our right or obligation to pay cash in lieu of all or a portion of such shares). If shares of our common stock are issued to the holders of the Convertible Notes upon conversion, there will be dilution to our stockholders’ equity, and the market price of our shares may decrease due to the additional selling pressure in the market. Any downward pressure on the price of our common stock caused by the sale or potential sale of shares issuable upon conversion of the Convertible Notes could also encourage short sales by third parties, creating additional selling pressure on our stock. The existence of the Convertible Notes and the obligations that we incurred by issuing them may restrict our ability to take advantage of certain future opportunities, such as engaging in future debt or equity financing activities.

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We will depend on Sanofi for the development and commercialization of aficamten in China and Bayer for the development and commercialization of aficamten in Japan.

Under the terms of our license and collaboration agreements, Sanofi is responsible for the development and commercialization of aficamten (to be commercialized as MYQORZO) in China and Bayer is responsible for the development and commercialization of aficamten in Japan. The timing and amount of any milestone and royalty payments we may receive under our license and collaboration agreements from Sanofi and Bayer will depend in part on the efforts and successful commercialization of aficamten by our out-license partners. We do not control the individual efforts of out-license partners, and any failure by our partners to devote sufficient time and effort to the development and commercialization of aficamten or to meet their respective obligations to us, including for future milestone and royalty payments; or to satisfactorily resolve significant disagreements with us could each have an adverse impact on our financial results and operations. We depend on our partners to comply with all applicable local laws relative to the development and commercialization of aficamten. If our partners violate, or are alleged to have violated, any laws or regulations during the performance of its obligations for us, it is possible that we could suffer financial and reputational harm or other negative outcomes, including possible legal consequences.

Any termination, breach or expiration of any of the license and collaboration agreements with Sanofi and Bayer could have a material adverse effect on our financial position by reducing or eliminating the potential for us to receive milestones and royalties. In such an event, we may be required to devote additional efforts and to incur additional costs associated with pursuing the development and commercialization of aficamten in China or Japan. Alternatively, we may attempt to identify and transact with a new licensee, but there can be no assurance that we would be able to identify a suitable licensee or transact on terms that are favorable to us.

Our ability to use net operating loss carryforwards and tax credit carryforwards to offset future taxable income may be subject to certain limitations, and ownership changes may limit our ability to use our net operating losses and tax credits in the future.

Our ability to use our federal and state NOLs to offset potential future taxable income and reduce related income taxes depends upon our generation of future taxable income. We cannot predict with certainty when, or whether, we will generate sufficient taxable income to use our NOLs. Under the Internal Revenue Code and similar state provisions, certain substantial changes in our ownership could result in an annual limitation on the amount of net operating loss and credit carryforwards that can be utilized in future years to offset future taxable income. The annual limitation may result in the expiration of net operating losses and credit carryforwards before utilization. We completed a Section 382 analysis through December 31, 2025, and concluded that an ownership change, as defined under Section 382, had not occurred

Any material limitation or expiration of our NOLs and tax credit carryforwards may harm our future net income by effectively increasing our future effective tax rate, which could result in a reduction in the market price of our common stock.

Legal and Compliance Risks

Legislation, such as the Inflation Reduction Act, or IRA, and the One Big Beautiful Bill Act, or OBBA, and potential future legislation may increase the difficulty and cost for us to obtain regulatory approval of, and to commercialize our products and to obtain Medicare coverage by 3rd party plans and affect the prices we may obtain upon commercialization.

The regulations that govern, among other things, regulatory approvals, coverage, pricing and reimbursement for new drug products vary widely from country to country. In the United States and some foreign jurisdictions, there have been a number of legislative and regulatory changes and proposed changes regarding the healthcare system that could prevent or delay regulatory approval of our product candidates, restrict or regulate post-approval activities and affect our ability to successfully sell MYQORZO or any other drug candidates for which we obtain regulatory approval.

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For example, in August 2022, the Inflation Reduction Act, or IRA, was signed into law, which, among other things, includes prescription drug provisions that may impact product pricing including the potential for net price reductions and/or the ability to increase price beyond the level of inflation over the lifecycle of our products, and/or may increase our rebate obligation to Medicare. The IRA implements inflation rebates in Medicare when a drug’s Average Manufacturer Price (AMP, in Part D) or Average Sale Price (ASP, in Part B) rises faster than the inflation index (CPI-U). In addition, the Part D drug benefit caps beneficiary spending at $2,000, eliminates the coverage gap for patients, and modifies, beginning in 2025, liabilities for drug manufacturers by replacing the 70% discount in the Coverage gap with a 10% discount in the Initial Coverage phase and a 20% discount in the Catastrophic phase. The IRA may also impact our ability to achieve broad coverage of our products by Medicare Plans as the IRA reduces the government’s and beneficiaries’ liability for drug spending while shifting costs to health plans and drug manufacturers. The IRA permits HHS to implement many of these provisions through guidance, as opposed to regulation, for the initial years. In addition, an executive order issued by the White House on May 12, 2025, [directs the Department of Health and Human Services ("HHS") to implement a “Most Favored Nation” drug pricing policy], and the recently-enacted One Big Beautiful Bill Act imposes new restrictions on funding for government health care programs and on individual eligibility for coverage under those programs, which may lead to lower reimbursements for drugs covered by those programs. More recently, HHS has begun announcing new drug payment models to lower drug prices for government health care program beneficiaries, such as the GUARD and GENEROUS models announced by the agency in late 2025. These models would use the prices other countries pay for drugs as benchmarks for determining whether manufacturers are required to offer additional rebates.

We cannot be sure whether additional legislation or rulemaking related to these developments will be issued or enacted, or what impact, if any, such changes will have on the profitability of MYQORZO, or any of our drug candidates, if approved for commercial use, in the future.

There have been, and likely will continue to be, legislative and regulatory proposals at the foreign, federal and state levels directed at broadening the availability of healthcare and containing or lowering the cost of healthcare. However, we cannot predict the timing or substance of proposals that may be adopted in the future, particularly in light of the difficulty of advancing legislation through Congress. The continuing efforts of governments, insurance companies, managed care organizations and other payors of healthcare services to contain or reduce costs of healthcare, including by imposing price controls, may adversely affect the demand and/or potential sales for MYQORZO and our product candidates for which we obtain regulatory approval and our ability to set a price that we believe is fair for our products. Any reduction in reimbursement from Medicare or other government programs may result in a similar reduction in payments from private payors.

We cannot predict the likelihood, nature, or extent of health reform initiatives that may arise from future legislation or administrative action and cannot predict the effect of any of such initiatives on our future financial results or the value of our common stock.

Our relationships with customers, healthcare providers, clinical trial sites and professionals and third-party payors will be subject to applicable anti-kickback, fraud and abuse and other laws and regulations. If we fail to comply with federal, state and foreign laws and regulations, including healthcare, privacy and data security laws and regulations, we could face criminal sanctions, civil penalties, contractual damages, reputational harm and diminished profits and future earnings.

Healthcare providers, including physicians and third-party payors play a primary role in the recommendation and prescription of any drug candidates for which we may obtain marketing approval. Our arrangements with customers, healthcare providers and third-party payors anywhere in the world may expose us to broadly applicable fraud and abuse and other healthcare laws and regulations that may constrain the business or financial arrangements and relationships through which we develop, and may market, sell and distribute, our products for which we obtain marketing approval.

Activities to ensure that our business arrangements with third parties will comply with applicable healthcare laws and regulations will involve substantial costs. It is possible that government authorities will conclude that our business practices may not comply with current or future statutes, regulations or case law involving applicable fraud and abuse or other healthcare laws and regulations. If our operations are found to be in violation of any of these laws or any other governmental regulations that may apply to us, we may be subject to significant civil, criminal and administrative penalties, damages, fines, exclusion from government funded healthcare programs, such as Medicare and Medicaid in the United States, and the curtailment or restructuring of our operations. Exclusion, suspension and debarment from government funded healthcare programs would significantly impact our ability to commercialize, sell or distribute any drug. If any of the physicians or other providers or entities with whom we expect to do business are found to be not in compliance with applicable laws, they may be subject to criminal, civil or administrative sanctions, including exclusions from government funded healthcare programs.

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We may be subject to costly product liability or other liability claims and may not be able to obtain adequate insurance.

The use of our drugs and drug candidates in clinical trials or by commercial patients may result in adverse events. We cannot predict all the possible harms or adverse events that may result from our clinical trials. We cannot predict all the possible harms or adverse events that may result from our clinical trials or the commercial use of any commercial products that may be approved in the future. We currently maintain limited product liability insurance, but such insurance may not be sufficient to cover any damages for which we may become liable, and we may be unable to continue to obtain such insurance on acceptable terms with adequate coverage, or at reasonable costs. Beyond insurance, we may not have sufficient resources to pay for any liabilities resulting from a personal injury or other claim.

We are subject to laws and regulations relating to privacy, data protection and the collection and processing of personal data. Failure to maintain compliance with these regulations could create additional liabilities for us.

The legislative and regulatory landscape for privacy and data protection continues to evolve in the U.S. and other jurisdictions around the world. For example, the California Consumer Privacy Act ("CCPA") affords California residents expanded privacy rights and protections, including civil penalties for violations and statutory damages under a private right of action for data security breaches. These protections were expanded by the California Privacy Rights Act ("CPRA") with the CPRA’s implementing regulations currently subject to a stay of enforcement until one year from their issuance. Privacy laws in other states may also impact our operations, including both comprehensive and sector-specific legislation, and Congress is also considering additional federal privacy legislation. In addition, most healthcare professionals and facilities are subject to privacy and security requirements under HIPAA with respect to our clinical and commercial activities. Although we are not considered to be a covered entity or business associate under HIPAA, we could be subject to penalties if we use or disclose individually identifiable health information in a manner not authorized or permitted by HIPAA. Other countries also have, or are developing, laws governing the collection, use and transmission of personal information. For example, in the EU, the GDPR regulates the processing of personal data of individuals within the EU, even if, under certain circumstances, that processing occurs outside the EU, and also places restrictions on transfers of such data to countries outside of the EU, including the U.S. Should we fail to provide adequate privacy or data security protections or maintain compliance with these laws and regulations, including the CCPA, as amended by the CPRA, as well as the GDPR, we could be subject to sanctions or other penalties, litigation, an increase in our cost of doing business and questions concerning the validity of our data processing activities, including clinical trials.

Responding to any claims relating to improper handling, storage or disposal of the hazardous chemicals and radioactive and biological materials we use in our business could be time-consuming and costly.

Our research and development processes involve the controlled use of hazardous materials, including chemicals and radioactive and biological materials. Our operations produce hazardous waste products. We cannot eliminate the risk of accidental contamination or discharge and any resultant injury from those materials. Federal, state and local laws and regulations govern the use, manufacture, storage, handling and disposal of hazardous materials. We may be sued for any injury or contamination that results from our or third parties’ use of these materials. Compliance with environmental laws and regulations is expensive, and current or future environmental regulations may impair our research, development and production activities.

Litigation may substantially increase our costs and harm our business.

We have been, and may in the future become, party to lawsuits including, without limitation, actions, claims and proceedings in the ordinary course of business relating to our directors, officers, stockholders, intellectual property, and employment matters and policies, which will cause us to incur legal fees and other costs related thereto, including potential expenses for the reimbursement of legal fees of officers and directors under indemnification obligations. The expense of defending against such claims or litigation may be significant and there can be no assurance that we will be successful in any defense. Further, the amount of time that may be required to resolve such claims or lawsuits is unpredictable, and these actions may divert management’s attention from the day-to-day operations of our business, which could adversely affect our business, results of operations, and cash flows. Litigation is subject to inherent uncertainties, and an adverse result in such matters that may arise from time to time could have a material adverse effect on our business, results of operations, and financial condition.

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General Risk Factors

Our failure to attract and retain skilled personnel could impair our drug development, commercialization and financial reporting activities.

Our business depends on the performance of our senior management and key scientific, commercial and technical personnel. The loss of the services of any member of our senior management or key scientific, technical, commercial or financial reporting staff may significantly delay or prevent the achievement of drug development and other business objectives by diverting management’s attention to transition matters and identifying suitable replacements. We also rely on consultants and advisors to assist us in formulating our research and development strategy. All of our consultants and advisors are either self-employed or employed by other organizations, and they may have conflicts of interest or other commitments, such as consulting or advisory contracts with other organizations, that may affect their ability to contribute to us. In addition, if and as our business grows, we will need to recruit additional executive management and scientific, technical and financial reporting personnel, particularly in Europe, where we need to build the corporate and commercial infrastructure, including identification and recruitment of qualified personnel to enable commercial operations by the time of a potential EMA approval of one of our drug candidates. There is intense competition for skilled executives and employees with relevant scientific and technical expertise, and this competition is likely to continue. Our inability to attract and retain sufficient scientific, technical, commercial and managerial personnel could limit or delay our product development or commercialization activities, which would adversely affect the development of our drug candidates and commercialization of our potential drugs and growth of our business.

Significant disruptions of information technology systems or breaches of data security could adversely affect our business.

Our business is increasingly dependent on complex and interdependent information technology systems, including internet-based systems, databases and programs, to support our business processes as well as internal and external communications. Despite the implementation of security measures, our internal computer systems and those of our third-party CROs, CMOs, supply chain partners, collaboration partners and other contractors and consultants are vulnerable to damage from computer viruses, unauthorized access, natural disasters, terrorism, war and telecommunication and electrical failures. As use of information technology systems has increased, deliberate attacks and attempts to gain unauthorized access to computer systems and networks have increased in frequency and sophistication. Furthermore, cybersecurity incidents increasingly involve the use of artificial intelligence and machine learning to launch more automated, targeted and coordinated attacks. Our information technology, systems and networks are potentially vulnerable to breakdown, malicious intrusion and computer viruses which may result in the impairment of production and key business processes or loss of data or information. We are also potentially vulnerable to data security breaches—whether by employees or others—which may expose sensitive data to unauthorized persons. We have in the past and may in the future be subject to security breaches. In December 2019, our IT systems were exposed to a ransomware attack, which partially impaired certain IT systems for a short period of time. Although we do not believe that we have experienced any material losses related to security breaches, including in recent email “phishing” incidents or the ransomware attack, there can be no assurance that we will not suffer such losses in the future. Breaches and other inappropriate access can be difficult to detect and any delay in identifying them could increase their harm, and it may take considerable time for us to investigate and evaluate the full impact of cyberattacks, particularly for sophisticated attacks, which may inhibit our ability to provide prompt, full, and reliable information about cybersecurity incidents to our customers, regulators, and the public. While we have implemented measures to protect our data security and information technology systems, such measures may not prevent these events. Any such breaches of security and inappropriate access could disrupt our operations, harm our reputation or otherwise have a material adverse effect on our business, financial condition and results of operations. For example, the loss of clinical study data from completed or ongoing clinical studies for any of our drug candidates could result in delays in our regulatory approval efforts and significantly increase our costs to recover or reproduce the data. In addition, our liability insurance, which includes cyber insurance, might not be sufficient in type or amount to cover us against claims related to cybersecurity incidents, attacks and other related incidents.

Our facilities in California are located near an earthquake fault, and an earthquake or other types of natural disasters, catastrophic events or resource shortages could disrupt our operations and adversely affect our results.

All our facilities and our important documents and records, such as hard and electronic copies of our laboratory books and records for our drug candidates and compounds and our electronic business records, are located in our corporate headquarters at a single location in South San Francisco, California near active earthquake zones. If a natural disaster, such as an earthquake, fire or flood, a catastrophic event such as a disease pandemic or terrorist attack, or a localized extended outage of critical utilities or transportation systems occurs, we could experience a significant business interruption. Our partners and other third parties on which we rely may also be subject to business interruptions from such events. In addition, California from time to time has experienced shortages of water, electric power and natural gas. Future shortages and conservation measures could disrupt our operations and cause expense, thus adversely affecting our business and financial results.

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We expect that our stock price will fluctuate significantly, and you may not be able to resell your shares at or above your investment price.

Our stock price experiences significant volatility, which often does not directly relate to our operating performance. For example, in 2024, the closing price of our common stock on the Nasdaq Global Select Market ranged from $46.36 to $108.06. Factors that have caused and could cause in the future volatility in the market price of our common stock include, but are not limited to: announcements concerning MYQORZO; any of the clinical trials for our drug candidates (including, but not limited to, the timing of initiation or completion of such trials and the results of such trials, and delays or discontinuations of such trials, including delays resulting from slower than expected or suspended patient enrollment or discontinuations resulting from a failure to meet pre-defined clinical end points); the commencement, settlement or adverse conclusion of litigation or a governmental investigation; failure or discontinuation of any of our research programs; issuance of new or changed securities analysts’ reports or recommendations; market conditions in the pharmaceutical, biotechnology and other healthcare-related sectors; actual or anticipated fluctuations in our financial and operating results; substantial sales of our common stock by our existing stockholders, whether or not related to our performance; and other factors described in this “Risk Factors” section.

Provisions in our charter documents and under Delaware law could discourage a takeover that stockholders may consider favorable and may lead to entrenchment of management.

Our amended and restated certificate of incorporation and amended and restated bylaws contain provisions that may discourage, delay or prevent a merger, acquisition or other change in control of us that stockholders may consider favorable, including transactions in which you might otherwise receive a premium for your shares. Among other things, these provisions: establish a classified board of directors with three-year staggered terms, which may delay the ability of stockholders to change the membership of a majority of our board of directors; prohibit removal of directors without cause; authorize our board of directors to issue preferred stock and to determine the price and other terms of those shares, including preferences and voting rights, without stockholder approval, which could be used to significantly dilute the ownership of a hostile acquirer; require the approval of at least two-thirds of the shares entitled to vote at an election of directors to adopt, amend or repeal our bylaws or our amended and restated certificate of incorporation regarding the election and removal of directors; do not allow stockholders to call a special meeting of stockholders; and require stock holders to provide advance notice in order to nominate candidates to our board of directors or to propose matters to be acted upon at a stockholders’ meeting, which may discourage or deter a potential acquirer from conducting a solicitation of proxies to elect the acquirer’s own slate of directors or otherwise attempting to obtain control of us.

We are also subject to the anti-takeover provisions contained in Section 203 of the Delaware General Corporation Law. Under Section 203, a corporation may not, in general, engage in a business combination with any holder of 15% or more of its capital stock unless the holder has held the stock for three years or, among other exceptions, the board of directors has approved the transaction. These provisions could discourage potential acquisition proposals and could delay or prevent a change in control transaction. They could also have the effect of discouraging others from making tender offers for our common stock, including transactions that may be in your best interests. These provisions may also prevent changes in our management or limit the price that investors are willing to pay for our stock.

ITEM 1B. UNRESOLVED STAFF COMMENTS

None.

ITEM 1C. CYBERSECURITY

Risk management and strategy

Cytokinetics recognizes the critical importance of developing, implementing, and maintaining cybersecurity measures designed to safeguard our information systems and protect the confidentiality, integrity, and availability of our critical data.

Managing Material Risks & Integrated Overall Risk Management

Our cybersecurity team, led by our Chief Information Security Officer, identifies and assesses risks from cybersecurity threats by monitoring and evaluating our threat environment and the Company’s risk profile using various methods including, for example, through manual and automated tools, internal and external audits, third-party threat assessments and third-party conducted red/blue team testing and tabletop incident response exercises and by subscribing to reports and services that identify cybersecurity threats, analyzing reports of threats and actors, conducting scans of the threat environment, evaluating our and our industry’s risk profile, evaluating threats reported to us, conducting threat assessments for internal and external threats and conducting vulnerability assessments.

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Depending on the environment, we implement and maintain various technical, physical, and organizational measures, processes, standards and policies designed to manage and mitigate material risks from cybersecurity threats to our Information Systems and Data, including, for example: maintaining an incident response plan, a vulnerability management policy, disaster recovery and business continuity plans and a vendor risk management program; conducting employee training, systems monitoring and penetration testing; implementing security standards, network security controls, access controls and physical security; encrypting and segregating data; though asset management, tracking and disposal; and maintaining cybersecurity insurance.

We have strategically integrated cybersecurity risk management into our broader risk management framework to promote a culture of cybersecurity risk management. This integration is designed to make cybersecurity considerations an integral part of our decision-making processes. Our risk management team works closely with our IT department and cybersecurity team to evaluate and address cybersecurity risks connected with our business objectives and operational needs.

Engage Third-Parties on Risk Management

Recognizing the complexity and evolving nature of cybersecurity threats, Cytokinetics engages with a range of external experts, including cybersecurity assessors, consultants, and auditors in evaluating and testing our risk management systems. These partnerships enable us to leverage specialized knowledge and insights. Our collaboration with these third parties includes periodic audits, threat assessments, and consultation on security enhancements.

Oversee Third-Party Risk

Because we are aware of the potentially material risks from cybersecurity threats associated with third-party service providers, Cytokinetics implements processes to oversee and manage these risks. Depending on the nature of the services provided and the identity of the service provider, we may conduct security assessments of the provider before engagement and may monitor their compliance with our cybersecurity policies after engagement. The monitoring includes periodic assessments by our Chief Information Security Officer and on an ongoing basis by our security specialists. This approach is designed to mitigate risks related to data breaches or other security incidents originating from third parties.

Risks from Cybersecurity Threats

Since the beginning of the last fiscal year, we have not identified risks from known cybersecurity threats, including as a result of any prior cybersecurity incidents, that have materially affected us. However, we face ongoing risks from cybersecurity threats that may materially affect the Company in the future. For more information, see Part I. Item 1A. Risk Factors in this Annual Report on Form 10-K, including the discussion under the heading “Significant disruptions of information technology systems or breaches of data security could adversely affect our business”.

Governance

Cytokinetics’ Board of Directors is aware of the critical nature of managing risks associated with cybersecurity threats. Our Board has established oversight mechanisms designed to ensure effective governance in managing material risks associated with cybersecurity threats because we recognize the significance of these threats to our operational integrity and stakeholder confidence.

Board of Directors Oversight

The Audit Committee is central to the Board’s oversight of cybersecurity risks and bears the primary responsibility for this domain. The Audit Committee is composed of Board members with diverse expertise, including, risk management, technology, and finance. The Audit Committee reports to the Board of Directors periodically regarding cybersecurity topics presented to the Audit Committee, and all materials made available to the Audit Committee are available to rest of the Board of Directors.

Management’s Role Managing Risk

Our Chief Information Security Officer, Chief Executive Officer and Chief Financial Officer play a pivotal role in informing the Audit Committee on cybersecurity risks. They provide cybersecurity briefings to the Audit Committee on a regular basis, at least once per year. These briefings encompass a broad range of topics, including as applicable: the current cybersecurity landscape and emerging threats, the status of ongoing cybersecurity initiatives and strategies, incident reports and learnings from any cybersecurity events, and compliance with regulatory requirements and industry practices.

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In addition to our scheduled meetings, the Audit Committee, our Chief Information Security Officer, Chief Executive Officer and Chief Financial Officer maintain an ongoing dialogue regarding emerging or potential cybersecurity risks. Together, they receive updates from one another, as appropriate, on any significant developments in the cybersecurity domain, ensuring the Board’s oversight is proactive and responsive. The Audit Committee actively participates in strategic decisions related to cybersecurity, offering guidance and approval for major initiatives. This involvement ensures that cybersecurity considerations are integrated into the broader strategic objectives of Cytokinetics. The Audit Committee conducts an annual review of the company’s cybersecurity posture and the effectiveness of its risk management strategies. This review helps in identifying areas for improvement and ensuring the alignment of cybersecurity efforts with the overall risk management framework.

Management Personnel in Cybersecurity

Primary responsibility for assessing, monitoring and managing our risks from cybersecurity threats rests with our Chief Information Security Officer, Mr. Eric Brown, Vice President of Information Technology.With over 10 years of experience in the field of cybersecurity and over 20 years of experience in IT more broadly, Mr. Brown brings a wealth of expertise to his role. His background includes extensive experience as an enterprise Chief Information Security Officer. His in-depth knowledge and experience are instrumental in developing and executing our cybersecurity strategies. Our Chief Information Security Officer has overall responsibility for the Company’s IT department and operations, including oversight over the cybersecurity team to ensure efforts to contain and remediate security incidents are sufficient and effective.

Monitor Cybersecurity Incidents

The CISO is responsible for staying apprised of the latest developments in cybersecurity, including potential threats and innovative risk management techniques. The CISO implements and oversees processes for the monitoring of our information systems. This includes the deployment of security measures and system audits to identify potential vulnerabilities. In the event of a cybersecurity incident, the CISO is equipped with a well-defined incident response plan. This plan includes immediate actions designed to mitigate the impact and long-term strategies for remediation and prevention of future incidents.

Reporting to Board of Directors

Our Chief Information Security Officer regularly informs our executive management team of material cybersecurity risks and incidents. This is how executive management is kept abreast of our cybersecurity posture and potentially material cybersecurity risks facing Cytokinetics. Furthermore, significant cybersecurity matters, and strategic risk management decisions are escalated by any of our executive officers to the Audit Committee, so that the Audit Committee can oversee and provide guidance on critical cybersecurity issues.

ITEM 2. PROPERTIES

Our material facilities consist of 234,892 square feet of leased office and laboratory space at 350 Oyster Point, South San Francisco, California. Our lease over this property expires in 2033.

We believe that these facilities are suitable and adequate for our current needs.

ITEM 3. LEGAL PROCEEDINGS

Judah Seidman, Individually and on Behalf of All Others Similarly Situated, Plaintiff, v. Cytokinetics, Incorporated and Robert I. Blum, Civil Action No.: 3:25-cv-07923

On September 17, 2025, a stockholder class action lawsuit (the "Action") was filed against the Company and its chief executive officer in the United States District Court for the Northern District of California, alleging certain violations under Sections 10(b) and 20(a) of the Securities Exchange Act of 1934. The Action was purportedly filed on behalf of a class consisting of all investors who purchased or otherwise acquired our common stock between December 27, 2023 and May 6, 2025. The Action alleges that the Company made materially false and misleading statements regarding the timeline for the NDA regulatory approval process for aficamten and that the Company failed to disclose related material risks. The complaint seeks unspecified damages, legal fees, and costs. On December 22, 2025, a lead plaintiff was appointed. The deadline for the lead plaintiff to file an amended compliant is March 10, 2026. We dispute any allegations of wrongdoing and intend to vigorously defend against the Action and expect to file a motion to dismiss within 60 days of the lead plaintiff filing an amended complaint.

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We are not presently a party to any other legal proceedings that in the opinion of our management, if determined adversely to us, would individually or taken together have a material adverse effect on our consolidated results of operations, financial condition or cash flows.

ITEM 4. MINE SAFETY DISCLOSURES

Not applicable.

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PART II

ITEM 5. MARKET FOR REGISTRANT’S COMMON EQUITY, RELATED STOCKHOLDER MATTERS AND ISSUER PURCHASES OF EQUITY SECURITIES

Market information for common stock

Our common stock is listed on the Nasdaq Global Select Market under the symbol “CYTK.”

Performance Graph

The comparisons in the table below are required by the SEC and are not intended to forecast or be indicative of possible future performance of our common stock. This graph shall not be deemed “soliciting material” or be deemed “filed” for purposes of Section 18 of the Exchange Act, or otherwise subject to the liabilities under that Section, and shall not be deemed to be incorporated by reference into any of our filings under the Securities Act, whether made before or after the date hereof and irrespective of any general incorporation language in any such filing, except to the extent we specifically incorporate it by reference into such filing.

The following graph compares cumulative total return of our common stock with the cumulative total return of (i) The Nasdaq Composite Index, and (ii) The Nasdaq Biotechnology Index. The graph assumes (a) $100 was invested on December 30, 2020 in each of our common stock, the stocks comprising the Nasdaq Composite Index and the stocks comprising the Nasdaq Biotechnology Index, and (b) the reinvestment of dividends into shares of common stock; however, no dividends have been declared on our common stock to date.

Holders of Record

As of February 23, 2026, we had38 holders of record of common stock. The number of holders of record is based upon the actual number of holders registered as of such date and does not include holders of shares in “street name” or persons, partnerships, associates, corporations or other entities in security position listings maintained by depositories.

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Dividends

We have never declared or paid, and do not anticipate declaring or paying in the foreseeable future, any cash dividends on our capital stock. Any future determination to declare cash dividends will be made at the discretion of our Board of Directors, subject to applicable laws, and will depend on our financial condition, results of operations, capital requirements, general business conditions and other factors that our board of directors may deem relevant.

Unregistered Sales of Equity Securities

None.

Issuer Purchases of Equity Securities

None.

ITEM 6. [RESERVED]

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ITEM 7. MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS

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.

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 healthspan of people with devastating cardiovascular and neuromuscular diseases of impaired muscle function. Our research and development activities relating to the biology of muscle function 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 objective to build a sustainable specialty biopharmaceutical business.

Our first commercial product is MYQORZOTM (aficamten), 5 mg, 10 mg, 15 mg, and 20 mg tablets which the FDA approved in December 2025. MYQORZO has since been approved in both the European Union and China. 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 to ensure the benefits of the drug outweigh 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 January 27, 2026 in the United States. We expect that MYQORZO will be made available in the European Union (starting with Germany in the second quarter) and China in 2026

For further information regarding our business, refer to Part I, Item 1. Business of this Annual Report on Form 10-K.

Liquidity and Capital Resources

Our cash, cash equivalents, and investments and a summary of our borrowings and working capital as of December 31, 2025 and 2024 are summarized as follows (in millions):

(In millions)

Financial assets:

Cash and cash equivalents $ 122.5 $ 94.9

Total cash, cash equivalents, and marketable securities $ 1,217.2 $ 1,221.2

Borrowings:

Liabilities related to RPI transactions measured at fair value 137.2 137.0

Working capital:

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The following table shows a summary of our cash flows for the periods set forth below (in millions):

Years Ended December 31,

(In millions)

Net cash used in operating activities $ (510.0 ) $ (395.9 ) $ (414.3 )

Net cash (used in) provided by investing activities 16.7 (553.1 ) 239.3

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. 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 $510.0 million and $395.9 million for 2025 and 2024, respectively, was largely due to ongoing research and development activities and general and administrative expenses to support research and development as well as commercial readiness. Net loss for 2025 and 2024 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 and the debt conversion expense due to 2027 Note repurchase.

Cash Flows Used in Investing Activities

Net cash used in investing activities of $16.7 million for 2025 was primarily due to maturities of investments, offset by purchases of investments and property, plant and equipment.

Net cash used in investing activities of $553.1 million for 2024 was primarily due to purchases of investments, offset by maturities of investments.

Cash Flows Provided by Financing Activities

Net cash provided by financing activities of $524.5 million in 2025 was primarily attributable to the issuance of the 2031 Notes of $750 million, $75.0 million and $100.0 million in proceeds from the drawing on Tranche 4 and Tranche 5 of the RP Multi Tranche Term Loan, respectively, and net proceeds from stock-based award activities partially offset with the 2031 Notes debt issuance costs of $20.4 million and the exchange of $402.5 million of 2027 Notes.

Net cash provided by financing activities of $930.6 million in 2024 was due to $250.0 million in proceeds from the 2024 RPI Transactions, $563.2 million of net proceeds from a public offering of common stock and issuances of common stock of $93.6 million under the Controlled Equity Offering Sales Agreement with Cantor Fitzgerald & Co, discussed below, and stock-based award activities.

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.

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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;

•

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 December 31, 2025. 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.

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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 22.6% and 23.5% as of December 31, 2025 and 2024, respectively.

2017 RP Omecamtiv Mecarbil Royalty Purchase Agreement

In February 2017, we entered into the RP OM RPA pursuant to which we sold a portion of our right to receive royalties from Amgen on future net sales of omecamtiv mecarbil to RPFT for a one-time payment of $90 million, which is non-refundable even if omecamtiv mecarbil is never commercialized. Concurrently, we entered into a common stock purchase agreement with RPFT through which RPFT purchased 875,656 shares of the Company’s common stock for $10.0 million. We allocated the consideration and issuance costs on a relative fair value basis to our liability to RPFT related to sale of future royalties under the RP OM RPA (the “RP OM Liability”) and the common stock sold to RPFT, which resulted in the RP OM Liability being initially recognized at $92.3 million. The RP OM RPA, as amended, provides for the sale of a royalty to RPFT of 5.5% on worldwide net sales of omecamtiv mecarbil.

We account for the RP OM Liability as a liability primarily because we have significant continuing involvement in generating the related revenue stream from which the liability will be repaid. If and when omecamtiv mecarbil is commercialized and royalties become due, we will recognize the portion of royalties paid to RPFT as a decrease to the RP OM Liability and a corresponding reduction in cash.

The carrying amount of the RP OM Liability is based on our estimate of the future royalties to be paid to RPFT 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 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% and approximately 0.1% as of December 31, 2025 and 2024, respectively.

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.

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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.

As of December 31, 2025, there remains $21.1 million aggregate principal amount of 2026 Notes outstanding reflected in current liabilities, $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 2026 Notes and 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.

Greater China Out-license for Omecamtiv Mecarbil

In December 2021, we entered into the Corxel OM License Agreement, pursuant to which we granted to Corxel an exclusive license to develop and commercialize omecamtiv mecarbil in China and Taiwan. In December 2024, we entered into a mutual termination agreement with Corxel to terminate the Corxel OM License Agreement. Accordingly, all rights to develop and commercialize omecamtiv mecarbil have reverted to us.

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.

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. 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.

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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 (equivalent to $11.8 million) in 2025. We expect to recognize an additional €10 million milestone payment 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 March 1, 2023, we entered into the Amended ATM Facility, with Cantor, under which we may offer and sell, from time to time at our sole discretion, shares of Common Stock having an aggregate offering price of up to $300.0 million through Cantor, as sales agent. The Amended ATM Facility amends, restates and supersedes the Controlled Equity Offering Sales Agreement dated as of March 6, 2019 between the Company and Cantor.

Under the Amended ATM Facility, Cantor sold Common Stock by a method that was deemed to be an “at the market offering” as defined in Rule 415 of the Securities Act of 1933, as amended, including sales made directly on the Nasdaq Global Select Market or any other trading market for Common Stock. Cantor was required to use commercially reasonable efforts to sell the Common Stock from time to time, based upon instructions from us (including any price, time or size limits or other customary parameters or conditions we may impose). We were required to pay Cantor a commission of up to 3.0% of the aggregate gross sales proceeds of any common stock sold through Cantor under the Amended ATM Facility, and we provided Cantor with customary indemnification rights. In 2023 and 2024, we issued 5,016,170 shares of our common stock for net proceeds of $164.2 million and 1,237,460 shares of our common stock for net proceeds of $93.6 million, respectively, under the Amended ATM Facility.

We exercised our rights to terminate the Amended ATM Facility with Cantor in February 2025.

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 December 31, 2025, we have not sold any shares of Common Stock under the Open Market Sale AgreementSM with Jefferies LLC.

Public Offering of Common Stock and Concurrent Private Offering

On May 28, 2024, we closed an underwritten public offering of 9,803,922 shares of Common Stock at a public offering price of $51.00 per share, which included the exercise in full by the underwriters of their option to purchase up to 1,470,588 shares of Common Stock at the public offering price. The gross proceeds to the Company from the offering were approximately $575 million and net proceeds were approximately $563.2 million, after deducting the applicable underwriting discounts and commissions. Concurrently with the closing of the underwritten public offering, RPI ICAV purchased 980,392 shares of Common Stock pursuant to the RP Stock Purchase Agreement, at a price of $51.00 per share in a concurrent private placement. The gross proceeds from the concurrent private placement were $50 million.

Future Uses of Cash

We expect that 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 (New York Heart Association, 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,

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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.

Our future capital uses and requirements depend on numerous factors. These factors include, but are not limited to, the following:

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the initiation, progress, timing, scope and completion of preclinical research, non-clinical development, CMC, and clinical trials for our drug candidates and other compounds;

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the time, costs and outcomes of regulatory reviews or other regulatory actions related to our drugs and drug candidates,

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the jurisdictions in which we are granted regulatory approvals and thus are able to successfully launch our products for commercial sale;

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delays that may be caused by requirements of regulatory agencies;

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our level of funding for the development of current or future drugs and drug candidates;

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the number of drug candidates we pursue and the stage of development that they are in;

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the costs involved in filing and prosecuting patent applications and attacking, enforcing or defending patent claims;

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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;

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our plans or ability to expand our drug development capabilities, including our capabilities to conduct clinical trials for our drug candidates;

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our plans or ability to engage third-party manufacturers for our drugs or drug candidates;

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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;

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the expansion and advancement of our research programs;

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the hiring of additional employees and consultants;

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the acquisition of technologies, products and other business opportunities that require financial commitments;

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our revenues from commercialization of MYQORZO and successful development and commercialization of any other drug candidates;

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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

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the payments due for interest on the term loan and convertible debt;

We have incurred an accumulated deficit of approximately $3.5 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.

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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.

Results of Operations

A discussion of our results of operations for the year ended December 31, 2023 and year-to-year comparisons between 2024 and 2023 can be found in Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations in our 2024 Annual Report on Form 10-K under the heading "Results of Operations."

Revenues

Our revenues since inception were primarily from our strategic alliances. We did not generate any revenue from commercial product sales prior to the year ended December 31, 2025. With the approval of MYQORZO for adults with symptomatic oHCM by the FDA in December 2025, we expect to start generating product revenue in the first quarter of 2026, and we expect commercial product revenues to increase over time as MYQORZO is accepted by physicians and patients.

Revenues in 2025, 2024, and 2023 were as follows (in millions):

Years Ended December 31, Change

(In millions)

License and milestone revenues for 2025 were from Bayer and Sanofi. Under the Bayer licensing agreement, we recognized $52.4 million related to the successful completion of the technology transfer and $11.8 million related to certain clinical milestones in 2025. Under the Sanofi License Agreement, we recognized $15.0 million in December 2025 as a result of milestones triggered by approvals of MYQORZO in the United States and China.

Collaboration revenues in 2025 were primarily from Bayer under the Bayer License Agreement related to certain research and development cost reimbursements.

As of December 31, 2025, the receivables balance is primarily comprised of $2.6 million related to Bayer and $15.1 million related to Sanofi.

License and milestone revenues recognized in 2024 were attributable to a $15.0 million non-refundable upfront payment from Corxel in the fourth quarter of 2024 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 in China and Taiwan to Sanofi. The $15.0 million was reflected as a receivable at December 31, 2024.

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Collaboration revenues in 2024 were primarily from Corxel under our collaboration and license agreement with Corxel. As of December 31, 2024 receivables of $1.5 million were recorded related to Corxel.

Research and Development Expenses

We incur research and development expenses associated with both partnered and our own research activities, which we finance from our own cash-on-hand, financing arrangements with third parties, and reimbursement from our collaboration partners.

Research and development expenses for 2025, 2024, and 2023 were as follows (in millions):

Years Ended December 31, Change

External costs: (In millions)

Internal costs:

Research and development expenses increased to $416.0 million in 2025 from $339.4 million in 2024, primarily due to advancing our clinical trials, higher personnel related costs including stock based compensation and medical affairs related activities.

We continue to develop aficamten to treat both oHCM and nHCM in two additional clinical trials: (i) ACACIA-HCM is a Phase 3 clinical trial for patients with symptomatic nHCM, and (ii) 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.

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 cover 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 is subject to a partial clinical hold from FDA that limits our ability to dose patients at doses anticipated to result in plasma exposures higher than certain levels, which may limit the ability of our Phase 1 trial to identify a therapeutic dose for CK-089. We conducted a Phase 1 evaluation, and we are in ongoing discussions with regulatory authorities to inform next steps.

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We expect that research and development expenses will be flat to declining in 2026 relative to 2025 due to the completion of MAPLE in 2025, the expected completion of ACACIA-HCM in the second half of 2026 partially offset by the continuation of COMET-HF,AMBER HFpEF and CEDAR-HCM.

General and Administrative Expenses

General and administrative expenses consist primarily of compensation for employees in executive and administrative functions, including, but not limited to, finance, human resources, legal, business and corporate development and strategic planning. Other significant costs include commercial readiness costs, facilities costs, consulting costs and professional fees for accounting and legal services, including legal services associated with obtaining and maintaining patents and regulatory compliance.

General and administrative expenses by program for 2025, 2024, and 2023 were as follows (in millions):

Years Ended December 31, Change

(In millions)

General and administrative expenses increased to $284.3 million in 2025 from $215.3 million in 2024, primarily due to investments toward commercial readiness including the hiring of our U.S. sales force primarily in the fourth quarter of 2025 and higher non-sales personnel related costs.

We expect sales, 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, included, 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. In addition, the Committee for Medicinal Products for Human Use of the European Medicines Agency adopted a positive opinion recommending marketing authorization in the European Union for MYQORZO for the treatment of adults with symptomatic oHCM, (New York Heart Association 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.

Interest Expense

Interest expense for 2025, 2024, and 2023 were as follows (in millions):

Years Ended December 31, Change

(In millions)

Term loan interest increased year over year due to drawing on Tranche 4 and Tranche 5 in 2025 and incurring a full year of interest on Tranche 6 of the RP Multi Tranche Loan. In September 2025, we issued the 2031 Notes and used the net proceeds and common stock to partially repurchase the 2027 Notes reducing 2027 Notes interest expense and incurring 2031 Notes interest expense. Interest expense in 2024 includes approximately $4.8 million of financing fees related to the 2024 RPI Transactions.

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.

Debt conversion expense

As a result of the partial repurchase of the 2027 Notes in the third quarter of 2025, we recorded $121.2 million in debt conversion expense, consisting of the difference between the consideration paid to the holders pursuant to the exchange agreements and the if-converted value of the 2027 Notes under the original terms.

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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.

Non-cash interest expense on liability related to the RP OM RPA and the RP Aficamten RPA in 2025, 2024, and 2023 were as follows (in millions):

Years Ended December 31, Change

(In millions)

RP OM Liability $ 0.1 $ 0.1 $ 3.9 $ — $ (3.8 )

Total non-cash interest expense recognized $ 58.3 $ 48.8 $ 29.4 $ 9.5 $ 19.4

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. In the second quarter of 2024, we recorded an additional $33.3 million to the carrying value related to the RP Aficamten RPA Amendment entered into May 22, 2024. The imputed rate of interest on the carrying value of the RP Aficamten Liability was approximately 22.6% as of December 31, 2025 and 23.5% as of December 31, 2024. The decline in the imputed rate of interest is due to a continued refinement of our assumptions including market and patient dynamics.

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 December 31, 2025 and approximately 0.1% as of December 31, 2024.

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 2025, 2024, and 2023 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 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 2025 were as follows (in millions):

Year Ended December 31 Change

(In millions)

RP Ulacamten RPA $ 0.3 $ (1.3 ) $ 1.6

RP Multi Tranche Loan Agreement Derivatives 4.2 1.3 2.9

Total change in fair value liabilities $ 4.0 $ (18.3 ) $ 22.3

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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 range from 10% to 18% as of December 31, 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.

The fair values of the derivative liabilities is 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 10% to 15% as of December 31, 2025) and other factors.

The total change in the estimated fair value liabilities for 2025, 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.

Critical Accounting Policies and Significant Estimates

Our discussion and analysis of our financial condition and results of operations are based on our financial statements, which have been prepared in accordance with accounting principles generally accepted in the United States. The preparation of these financial statements requires us to make estimates and judgments that affect the reported amounts of assets, liabilities and expenses and related disclosure of contingent assets and liabilities. We review our estimates on an ongoing basis. We base our estimates on historical experience and on various other assumptions that we believe to be reasonable under the circumstances. Actual results may differ from these estimates under different assumptions or conditions. While our significant accounting policies are described in more detail in the notes to our financial statements included in this Annual Report on Form 10-K, we believe the following accounting policies to be critical to the judgments and estimates used in the preparation of our financial statements

Fair Value Liabilities

CYTK US Equity

CYTK · 10-K · period ended 2025-12-31

ITEM 1A. RISK FACTORS

ITEM 1B. UNRESOLVED STAFF COMMENTS

ITEM 1C. CYBERSECURITY

ITEM 2. PROPERTIES

ITEM 3. LEGAL PROCEEDINGS

ITEM 4. MINE SAFETY DISCLOSURES

ITEM 5. MARKET FOR REGISTRANT’S COMMON EQUITY, RELATED STOCKHOLDER MATTERS AND ISSUER PURCHASES OF EQUITY SECURITIES

ITEM 6. [RESERVED]

ITEM 7. MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS

CYTK US Equity☆

CYTK · 10-K · period ended 2025-12-31

ITEM 1A. RISK FACTORS

ITEM 1B. UNRESOLVED STAFF COMMENTS

ITEM 1C. CYBERSECURITY

ITEM 2. PROPERTIES

ITEM 3. LEGAL PROCEEDINGS

ITEM 4. MINE SAFETY DISCLOSURES

ITEM 5. MARKET FOR REGISTRANT’S COMMON EQUITY, RELATED STOCKHOLDER MATTERS AND ISSUER PURCHASES OF EQUITY SECURITIES

ITEM 6. [RESERVED]

ITEM 7. MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS

CYTK US Equity