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UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 10-Q

(Mark One)

☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the quarterly period ended March 31, 2026

or

☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the transition period from to

Commission file number: 000-50633

CYTOKINETICS, INCORPORATED

(Exact name of registrant as specified in its charter)

Delaware | 94-3291317
(State or other jurisdiction of incorporation or organization) | (I.R.S. Employer Identification No.)
350 Oyster Point Blvd. South San Francisco, California | 94080
(Address of principal executive offices) | (Zip Code)

Registrant’s telephone number, including area code: (650) 624-3000

Securities registered pursuant to Section 12(b) of the Act:

Title of each class Common Stock, $0.001 par value | Trading symbol CYTK | Name of each exchange on which registered The Nasdaq Global Select Market

Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days. Yes ☒ No ☐

Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T (§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit such files). Yes ☒ No ☐

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company” and “emerging growth company” in Rule 12b-2 of the Exchange Act.

Large accelerated filer ☑ |  | Accelerated filer ☐ |  | Non-accelerated filer ☐ |  | Smaller reporting company ☐ |  | Emerging growth company ☐ |

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act). Yes ☐ No ☒

Number of shares of common stock, $0.001 par value, outstanding as of May 4, 2026: 124,432,565

Table of Contents

CYTOKINETICS, INCORPORATED

TABLE OF CONTENTS FOR FORM 10-Q

FOR THE three months ended March 31, 2026

| Page
Glossary of Terms | 3
PART I. FINANCIAL INFORMATION | 7
Item 1. Financial Statements (Unaudited) | 7
Condensed Consolidated Balance Sheets | 7
Condensed Consolidated Statements of Operations and Comprehensive Loss | 8
Condensed Consolidated Statements of Stockholders’ Deficit | 9
Condensed Consolidated Statements of Cash Flows | 10
Notes to Condensed Consolidated Financial Statements | 11
Item 2. Management’s Discussion and Analysis of Financial Condition and Results of Operations | 22
Item 3. Quantitative and Qualitative Disclosures About Market Risk | 39
Item 4. Controls and Procedures | 39
PART II. OTHER INFORMATION | 40
Item 1. Legal Proceedings | 40
Item 1A. Risk Factors | 41
Item 2. Unregistered Sales of Equity Securities and Use of Proceeds | 56
Item 3. Defaults Upon Senior Securities | 56
Item 4. Mine Safety Disclosures | 56
Item 5. Other Information | 56
Item 6. Exhibits | 57
SIGNATURES | 59

2

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# Glossary of Terms

Unless the context requires otherwise, references to “Cytokinetics,” “the Company,” “we,” “us” or “our” in this Quarterly Report on Form 10-Q refer to Cytokinetics, Incorporated and its subsidiaries. References to “Notes” in this Form 10-Q are to the Notes to the Condensed Consolidated Financial Statements in this Form 10-Q. We also have used other specific terms in this Form 10-Q, most of which are explained or defined below:

Term/Abbreviation |  | Definition
2004 Plan |  | Cytokinetics’ Amended and Restated 2004 Equity Incentive Plan
2022 RPI Transactions |  | The transactions contemplated by the RP Multi Tranche Loan Agreement and the RP Aficamten RPA
2024 RPI Transactions |  | The transactions contemplated by the 2024 RP OM Loan Agreement, the RP Ulacamten RPA, the RP Stock Purchase Agreement, the 2022 RP Multi Tranche Loan Agreement Amendment and the RP Aficamten RPA Amendment
2026 Indenture |  | Indenture, dated November 13, 2019, between Cytokinetics and U.S. Bank Trust Company (successor in interest to U.S. Bank National Association), as trustee, as supplemented by the First Supplemental Indenture, dated November 13, 2019, between Cytokinetics and U.S. Bank Trust Company (successor in interest to U.S. Bank National Association)
2026 Notes |  | Cytokinetics’ 4% convertible senior notes due 2026
2027 Indenture |  | Indenture, dated July 6, 2022, between Cytokinetics and U.S. Bank Trust Company, as trustee
2027 Notes |  | Cytokinetics’ 3.50% convertible senior notes due 2027
2031 Indenture |  | Indenture, dated September 19, 2025, between Cytokinetics and U.S. Bank Trust Company, as trustee
2031 Notes |  | Cytokinetics’ 1.75% convertible senior notes due 2031
ACACIA-HCM |  | Assessment Comparing Aficamten to Placebo on Cardiac Endpoints In Adults with Non-Obstructive HCM
AMBER-HFpEF |  | Our Phase 2 randomized, placebo-controlled, double-blind, multi-center, dose-finding clinical trial in patients with symptomatic HFpEF with left ventricular ejection fraction ≥ 60%
Amended ATM Facility |  | Our amended and restated Controlled Equity Offering Sales Agreement
Astellas FSRA Agreement |  | Fast Skeletal Regulatory Activator Agreement, dated April 23, 2020 between Cytokinetics and Astellas
Bayer |  | Means Bayer AG and/or any affiliate thereof, including Bayer Consumer Care AG
Bayer License Agreement |  | Means that certain License and Collaboration Agreement, dated November 18, 2024 by and between the Company and Bayer Consumer Care AG, pursuant to which Bayer acquired an exclusive license to develop and commercialize aficamten in Japan, subject to certain reserved development rights.
Cantor |  | Cantor Fitzgerald & Co.
CEDAR-HCM |  | Our clinical trial of aficamten in a pediatric population with oHCM
cGCP |  | Current Good Clinical Practice
cGLP |  | Current Good Laboratory Practice
cGMP |  | Current Good Manufacturing Practice
China |  | People's Republic of China (including the Hong Kong and Macau SARs)
CMC |  | Chemistry, Manufacturing and Controls
CMO |  | Contract Manufacturing Organizations
COMET-HF |  | Our Phase 3 multi-center, double-blind, randomized, placebo-controlled trial to assess the efficacy and safety of omecamtiv mecarbil in patients with symptomatic HFrEF with severely reduced ejection fraction
Common Stock |  | Our common stock, par value $0.001 per share
Compensation Committee |  | Compensation and Talent Committee of Cytokinetics’ Board of Directors
Convertible Notes |  | 2026 Notes, 2027 Notes, and 2031 Notes

3

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Corxel |  | Corxel Pharmaceuticals Limited (formerly known as Ji Xing Pharmaceuticals Limited) and/or its affiliates, including Corxel Pharmaceuticals Hong Kong Limited
Corxel OM License Agreement |  | Means that certain Collaboration and License Agreement, dated December 20, 2021, by and between the Company and Corxel, pursuant to which we granted Corxel an exclusive license to develop and commercialize omecamtiv mecarbil in China and Taiwan
COURAGE-ALS |  | Clinical Outcomes Using Reldesemtiv on ALSFRS-R in a Global Evaluation in ALS
CRO |  | Contract Research Organization
CV |  | Cardiovascular
E.U. or EU |  | European Union
EMA |  | European Medicines Agency
ESPP |  | Employee Stock Purchase Plan
ETASU |  | Elements to assure safe use
Exchange Act |  | Securities Exchange Act of 1934, as amended
FDA |  | U.S. Food and Drug Administration
Final Payment Amount |  | As defined in Part I, Item 2 (Management’s Discussion and Analysis of Financial Conditions and Results of Operations) of this Quarterly Report on Form 10-Q – Sources and Uses of Cash, Royalty Pharma Transactions
FOREST-HCM |  | Five-Year, Open-Label, Research Evaluation of Sustained Treatment with Aficamten in HCM
Fundamental Change |  | As defined in the 2026 Indenture, 2027 Indenture, or 2031 Indenture, as applicable
GAAP |  | Generally Accepted Accounting Principles in the U.S.
GALACTIC-HF |  | Global Approach to Lowering Adverse Cardiac Outcomes Through Improving Contractility in Heart Failure
GDPR |  | General Data Protection Regulation ((EU) 2016/679)
HCM |  | Hypertrophic cardiomyopathy
HFpEF |  | Heart failure with preserved ejection fraction
HFrEF |  | Heart failure with reduced ejection fraction
HHS |  | U.S. Department of Health and Human Services
HIPAA |  | The federal Health Insurance Portability and Accountability Act of 1996, as amended by the Health Information Technology for Economic and Clinical Health Act
IND |  | Investigational New Drug
IRA |  | Inflation Reduction Act of 2022
KCCQ |  | Kansas City Cardiomyopathy Questionnaire
KCCQ-OSS |  | KCCQ Overall Summary Score
LVEF |  | Left ventricular ejection fraction
LVOT |  | Left ventricular outflow tract
LVOT-G |  | Left ventricular outflow tract gradient
MAA |  | Marketing Authorization Application
MAPLE-HCM |  | Metoprolol vs Aficamten in Patients with LVOT Obstruction on Exercise Endpoints Capacity in HCM
NDA |  | New Drug Application
nHCM |  | Non-obstructive HCM
NOLs |  | Net operating loss carryforward
NYHA |  | New York Heart Association
oHCM |  | Obstructive HCM

4

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Oyster Point Lease |  | Lease, dated July 24, 2019, by and between Cytokinetics and KR Oyster Point 1, LLC, as amended
Partial Redemption Limitation |  | As defined in the 2027 Indenture and 2031 Indenture, as applicable
PSU |  | Performance Stock Unit
Radnor Lease |  | As defined in Part I, Item 1 (Financial Statements (Unaudited)), Notes to Condensed Consolidated Financial Statements of this Quarterly Report on Form 10-Q - Note 9 (Commitments and Contingencies) – Operating Leases
REMS |  | Risk Evaluation and Mitigation Strategy
RP Aficamten RPA |  | Revenue Participation Right Purchase Agreement, dated January 7, 2022, by and between Cytokinetics and Royalty Pharma Investments 2019 ICAV
RP Aficamten RPA Amendment |  | Amendment No. 1, dated May 22, 2024, to Revenue Participation Right Purchase Agreement, dated January 7, 2022, by and between Cytokinetics and Royalty Pharma Investments 2019 ICAV
RP Ulacamten RPA |  | Ulacamten Revenue Participation Right Purchase Agreement, dated May 22, 2024, by and between Cytokinetics and Royalty Pharma Investments 2019 ICAV
RP Multi Tranche Loan Agreement |  | Development Funding Loan Agreement, dated January 7, 2022, by and among Royalty Pharma Development Funding, LLC and Cytokinetics
RP Multi Tranche Loan Agreement Amendment |  | Third Amendment, dated May 22, 2024, to Development Funding Loan Agreement, dated January 7, 2022, by and among Royalty Pharma Development Funding, LLC and Cytokinetics
RP OM Liability |  | As defined in Part I, Item 1 (Financial Statements (Unaudited)), Notes to Condensed Consolidated Financial Statements of this Quarterly Report on Form 10-Q - Note 3 (Agreements with Royalty Pharma) – 2017 RP Omecamtiv Mecarbil Royalty Purchase Agreement
RP OM Loan Agreement |  | 2024 Development Funding Loan Agreement, dated May 22, 2024, by and among Royalty Pharma Development Funding, LLC and Cytokinetics
RP OM RPA |  | Royalty Purchase Agreement, dated February 1, 2017, by and between Cytokinetics and RPI Finance Trust, as amended by Amendment No. 1, dated January 7, 2022
RP Stock Purchase Agreement |  | Common Stock Option and Purchase Agreement, dated May 22, 2024, by and between Cytokinetics and Royalty Pharma Investments 2019 ICAV
RPDF |  | Royalty Pharma Development Funding, LLC
RPFT |  | RPI Finance Trust
RPI ICAV |  | Royalty Pharma Investments 2019 ICAV
RSU |  | Restricted Stock Unit
Sanofi |  | Means Sanofi S.A. and/or any affiliates thereof, including Genzyme Corporation
Sanofi License Agreement |  | Means that certain License and Collaboration Agreement, dated July 14, 2020 by and between the Company and Sanofi (as assignee of Corxel), pursuant to which Sanofi has an exclusive license to develop and commercialize aficamten in China and Taiwan
Section 382 |  | Section 382 of the Internal Revenue Code
Securities Act |  | Securities Act of 1933, as amended
SEQUOIA-HCM |  | Safety, Efficacy, and Quantitative Understanding of Obstruction Impact of Aficamten in HCM
SGLT2 |  | Sodium-glucose cotransporter-2
U.S. or US |  | United States of America

This Form 10-Q includes discussion of certain clinical studies relating to various in-line products and/or product candidates. These studies typically are part of a larger body of clinical data relating to such products or product candidates, and the discussion herein should be considered in the context of the larger body of data. In addition, clinical trial data are subject to differing interpretations, and, even when we view data as sufficient to support the safety and/or effectiveness of a product candidate or a new indication for an in-line product, regulatory authorities may not share our views and may require additional data or may deny approval altogether.

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CYTOKINETICS and our C-shaped logo are registered trademarks of Cytokinetics in the U.S. and certain other countries. Other service marks, trademarks and trade names referred to in this report are the property of their respective owners.

The information contained on our website, our Facebook, Instagram, YouTube and LinkedIn pages or our X (formerly Twitter) accounts, or any third-party website, is not incorporated by reference into this Form 10-Q.

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PART I. FINANCI AL INFORMATION

ITEM 1. FINANCI AL STATEMENTS

CYTOKINETICS, INCORPORATED

CONDENSED CONSOLIDAT ED BALANCE SHEETS

(In thousands) (Unaudited)

|  | March 31, 2026 |  |  | December 31, 2025 |
ASSETS |  |  |  |  |  |
Current assets: |  |  |  |  |  |
Cash and cash equivalents |  | $ | 129,843 |  |  | $ | 122,518 |
Short-term investments |  |  | 688,707 |  |  |  | 759,703 |
Accounts receivable, net |  |  | 6,827 |  |  |  | 17,764 |
Inventories |  |  | 154 |  |  |  | — |
Prepaid expenses and other current assets |  |  | 13,934 |  |  |  | 16,990 |
Total current assets |  |  | 839,465 |  |  |  | 916,975 |
Long-term investments |  |  | 254,719 |  |  |  | 335,048 |
Property and equipment, net |  |  | 82,438 |  |  |  | 79,194 |
Operating lease right-of-use assets |  |  | 74,545 |  |  |  | 75,979 |
Inventories, long-term |  |  | 3,843 |  |  |  | — |
Other assets |  |  | 18,468 |  |  |  | 17,341 |
Total assets |  | $ | 1,273,478 |  |  | $ | 1,424,537 |
LIABILITIES AND STOCKHOLDERS’ DEFICIT |  |  |  |  |  |
Current liabilities: |  |  |  |  |  |
Accounts payable |  | $ | 24,709 |  |  | $ | 22,337 |
Accrued liabilities |  |  | 68,863 |  |  |  | 83,278 |
Short-term operating lease liabilities |  |  | 20,960 |  |  |  | 19,111 |
Current portion of convertible and long-term debt |  |  | 44,808 |  |  |  | 41,181 |
Derivative liabilities measured at fair value |  |  | 29,600 |  |  |  | 31,100 |
Deferred revenue |  |  | 1,653 |  |  |  | 1,612 |
Other current liabilities |  |  | 8,592 |  |  |  | 3,833 |
Total current liabilities |  |  | 199,185 |  |  |  | 202,452 |
Term loans, net |  |  | 247,209 |  |  |  | 246,384 |
Convertible notes, net |  |  | 870,511 |  |  |  | 869,597 |
Liabilities related to revenue participation right purchase agreements, net |  |  | 539,106 |  |  |  | 520,559 |
Long-term operating lease liabilities |  |  | 105,235 |  |  |  | 107,970 |
Liabilities related to RPI Transactions measured at fair value |  |  | 138,800 |  |  |  | 137,200 |
Total liabilities |  |  | 2,100,046 |  |  |  | 2,084,162 |
Commitments and contingencies |  |  |  |  |  |
Stockholders' deficit |  |  |  |  |  |
Preferred stock |  |  | — |  |  |  | — |
Common stock |  |  | 124 |  |  |  | 123 |
Additional paid-in capital |  |  | 2,867,670 |  |  |  | 2,826,341 |
Accumulated other comprehensive (loss) income |  |  | (1,612 | ) |  |  | 630 |
Accumulated deficit |  |  | (3,692,750 | ) |  |  | (3,486,719 | )
Total stockholders' deficit |  |  | (826,568 | ) |  |  | (659,625 | )
Total liabilities and stockholders' deficit |  | $ | 1,273,478 |  |  | $ | 1,424,537 |

The accompanying notes are an integral part of these condensed consolidated financial statements.

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CYTOKINETICS, INCORPORATED

CONDENSED CONSOLIDATED STATEMENTS O F OPERATIONS AND COMPREHENSIVE LOSS

(In thousands, except per share data) (Unaudited)

|  | Three Months Ended |
|  | March 31, 2026 |  |  | March 31, 2025 |
Revenues: |  |  |  |  |  |
Net product revenue |  | $ | 4,789 |  |  | $ | — |
Collaboration revenues |  |  | 2,637 |  |  |  | 1,579 |
License and milestone revenues |  |  | 11,929 |  |  |  | — |
Total revenues |  |  | 19,355 |  |  |  | 1,579 |
Operating expenses: |  |  |  |  |  |
Research and development |  |  | 95,525 |  |  |  | 98,262 |
Selling, general and administrative |  |  | 104,896 |  |  |  | 57,369 |
Cost of goods sold |  |  | 160 |  |  |  | — |
Collaboration cost of revenues |  |  | 2,392 |  |  |  | 1,579 |
Total operating expenses |  |  | 202,973 |  |  |  | 157,210 |
Operating loss |  |  | (183,618 | ) |  |  | (155,631 | )
Interest and other expense, net |  |  | (14,519 | ) |  |  | (8,868 | )
Non-cash interest expense on liabilities related to revenue participation right purchase agreements |  |  | (18,816 | ) |  |  | (14,078 | )
Interest and other income, net |  |  | 11,022 |  |  |  | 13,701 |
Change in fair value of derivative liabilities |  |  | 1,500 |  |  |  | (400 | )
Change in fair value of liabilities related to RPI Transactions |  |  | (1,600 | ) |  |  | 3,900 |
Net loss |  | $ | (206,031 | ) |  | $ | (161,376 | )
Net loss per share — basic and diluted |  | $ | (1.67 | ) |  | $ | (1.36 | )
Weighted-average number of shares used in computing net loss per share — basic and diluted |  |  | 123,273 |  |  |  | 118,496 |
Other comprehensive (loss) gain: |  |  |  |  |  |
Unrealized loss on available-for-sale securities, net |  |  | (1,838 | ) |  |  | (541 | )
Foreign currency translation adjustments |  |  | (404 | ) |  |  | (312 | )
Comprehensive loss |  | $ | (208,273 | ) |  | $ | (162,229 | )

The accompanying notes are an integral part of these condensed consolidated financial statements.

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CYTOKINETICS, INCORPORATED

CONDENSED CONSOLIDATED STATEMENTS OF STOCKHOLDERS’ (Deficit) equity

(In thousands, except share data) (Unaudited)

|  | Common Stock |  |  | Additional Paid-In |  |  | Accumulated Other Comprehensive |  |  | Accumulated |  |  | Total Stockholders’ |
|  | Shares |  |  | Amount |  |  | Capital |  |  | Income |  |  | Deficit |  |  | Deficit |
Balance, December 31, 2025 |  |  | 122,943,172 |  |  | $ | 123 |  |  | $ | 2,826,341 |  |  | $ | 630 |  |  | $ | (3,486,719 | ) |  | $ | (659,625 | )
Exercise of stock options |  |  | 403,208 |  |  |  | — |  |  |  | 11,346 |  |  |  | — |  |  |  | — |  |  |  | 11,346 |
Vesting of restricted stock units, net of taxes withheld |  |  | 891,443 |  |  |  | 1 |  |  |  | (841 | ) |  |  | — |  |  |  | — |  |  |  | (840 | )
Stock-based compensation |  |  | — |  |  |  | — |  |  |  | 30,824 |  |  |  | — |  |  |  | — |  |  |  | 30,824 |
Unrealized loss on available-for-sale securities, net |  |  | — |  |  |  | — |  |  |  | — |  |  |  | (1,838 | ) |  |  | — |  |  |  | (1,838 | )
Foreign currency translation adjustments |  |  | — |  |  |  | — |  |  |  | — |  |  |  | (404 | ) |  |  | — |  |  |  | (404 | )
Net loss |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | (206,031 | ) |  |  | (206,031 | )
Balance, March 31, 2026 |  |  | 124,237,823 |  |  | $ | 124 |  |  | $ | 2,867,670 |  |  | $ | (1,612 | ) |  | $ | (3,692,750 | ) |  | $ | (826,568 | )

|  | Common Stock |  |  | Additional Paid-In |  |  | Accumulated Other Comprehensive |  |  | Accumulated |  |  | Total Stockholders’ |
|  | Shares |  |  | Amount |  |  | Capital |  |  | Income |  |  | Deficit |  |  | Deficit |
Balance, December 31, 2024 |  |  | 118,209,139 |  |  | $ | 118 |  |  | $ | 2,563,876 |  |  | $ | 2,398 |  |  | $ | (2,701,764 | ) |  | $ | (135,372 | )
Exercise of stock options |  |  | 351,985 |  |  |  | — |  |  |  | 7,651 |  |  |  | — |  |  |  | — |  |  |  | 7,651 |
Vesting of restricted stock units, net of taxes withheld |  |  | 659,179 |  |  |  | 1 |  |  |  | (13 | ) |  |  | — |  |  |  | — |  |  |  | (12 | )
Stock-based compensation |  |  | — |  |  |  | — |  |  |  | 23,549 |  |  |  | — |  |  |  | — |  |  |  | 23,549 |
Unrealized loss on available-for-sale securities, net |  |  | — |  |  |  | — |  |  |  | — |  |  |  | (541 | ) |  |  | — |  |  |  | (541 | )
Foreign currency translation adjustments |  |  | — |  |  |  | — |  |  |  | — |  |  |  | (312 | ) |  |  | — |  |  |  | (312 | )
Net loss |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | (161,376 | ) |  |  | (161,376 | )
Balance, March 31, 2025 |  |  | 119,220,303 |  |  | $ | 119 |  |  | $ | 2,595,063 |  |  | $ | 1,545 |  |  | $ | (2,863,140 | ) |  | $ | (266,413 | )

The accompanying notes are an integral part of these condensed consolidated financial statements.

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CYTOKINETICS, INCORPORATED

CONDENSED CONSOLIDATED S TATEMENTS OF CASH FLOWS

(In thousands) (Unaudited)

|  | Three Months Ended |
|  | March 31, 2026 |  |  | March 31, 2025 |
Cash flows from operating activities: |  |  |  |  |  |
Net loss |  | $ | (206,031 | ) |  | $ | (161,376 | )
Adjustments to reconcile net loss to net cash used in operating activities: |  |  |  |  |  |
Non-cash interest expense on liabilities related to revenue participation right purchase agreements |  |  | 18,816 |  |  |  | 14,104 |
Stock-based compensation expense |  |  | 30,394 |  |  |  | 23,549 |
Non-cash lease expense |  |  | 1,585 |  |  |  | 1,230 |
Depreciation of property and equipment |  |  | 3,378 |  |  |  | 2,300 |
Change in fair value of derivative liabilities |  |  | (1,500 | ) |  |  | 400 |
Change in fair value of liabilities related to RPI Transactions |  |  | 1,600 |  |  |  | (3,900 | )
Realized gain on investment, net |  |  | (61 | ) |  |  | — |
Interest receivable and amortization on investments |  |  | (1,874 | ) |  |  | (6,174 | )
Non-cash interest expense related to debt |  |  | 8,455 |  |  |  | 3,453 |
Changes in operating assets and liabilities: |  |  |  |  |  |
Accounts receivable |  |  | 10,937 |  |  |  | 14,638 |
Prepaid and other assets |  |  | 2,057 |  |  |  | (376 | )
Inventories |  |  | (3,567 | ) |  |  | — |
Accounts payable |  |  | 1,519 |  |  |  | (4,576 | )
Deferred revenue |  |  | 41 |  |  |  | — |
Accrued and other liabilities |  |  | (6,213 | ) |  |  | (14,367 | )
Operating lease liabilities |  |  | (1,039 | ) |  |  | (2,143 | )
Other non-current liabilities |  |  | (3,954 | ) |  |  | 1,621 |
Net cash used in operating activities |  |  | (145,457 | ) |  |  | (131,617 | )
Cash flows from investing activities: |  |  |  |  |  |
Purchases of investments |  |  | (106,516 | ) |  |  | (159,105 | )
Investment in non-marketable equity security |  |  | — |  |  |  | (5,000 | )
Maturities of investments |  |  | 257,938 |  |  |  | 275,725 |
Purchases of property and equipment |  |  | (5,930 | ) |  |  | (5,664 | )
Net cash provided by investing activities |  |  | 145,492 |  |  |  | 105,956 |
Cash flows from financing activities: |  |  |  |  |  |
Repayment of finance lease liabilities |  |  | — |  |  |  | (202 | )
Repayment of term loans |  |  | (2,735 | ) |  |  | (2,682 | )
Proceeds from issuance of common stock under equity incentive and stock purchase plans |  |  | 11,346 |  |  |  | 7,651 |
Taxes paid related to net share settlement of equity awards |  |  | (841 | ) |  |  | (13 | )
Net cash provided by financing activities |  |  | 7,770 |  |  |  | 4,754 |
Effect of exchange rate changes on cash |  |  | (483 | ) |  |  | (270 | )
Net increase (decrease) in cash, cash equivalents, and restricted cash |  |  | 7,322 |  |  |  | (21,177 | )
Cash, cash equivalents, and restricted cash, beginning of period |  |  | 125,632 |  |  |  | 95,232 |
Cash, cash equivalents, and restricted cash, end of period |  | $ | 132,954 |  |  | $ | 74,055 |
Supplemental cash flow disclosures: |  |  |  |  |  |
Cash paid for interest |  | $ | 1,585 |  |  | $ | 9,647 |
Non-cash investing and financing activities: |  |  |  |  |  |
Right-of-use assets recognized in exchange for operating lease obligations |  | $ | 170 |  |  | $ | 3,501 |
Amounts unpaid for purchases of property and equipment |  | $ | 4,186 |  |  | $ | 1,494 |

The accompanying notes are an integral part of these condensed consolidated financial statements.

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CYTOKINETICS, INCORPORATED

NOTES TO UNAUDITED CONDENSED CON SOLIDATED FINANCIAL STATEMENTS

Note 1 — Organization and Significant Accounting Policies

Cytokinetics, Incorporated was incorporated under the laws of the state of Delaware on August 5, 1997. 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. Our flagship commercial product is MYQORZO® (aficamten), 5 mg, 10 mg, 15 mg, and 20 mg tablets for the treatment of adults with oHCM to improve functional capacity and symptoms, which the FDA approved in December 2025 and which first became available for prescription to patients in the first quarter of 2026.

Our financial statements contemplate the conduct of our operations in the normal course of business. We have incurred an accumulated deficit of approximately $3.7 billion since inception and there can be no assurance that we will attain profitability. We had a net loss of $206.0 million and net cash used in operations of $145.5 million for the three months ended March 31, 2026. Cash, cash equivalents, and investments was $1.1 billion as of March 31, 2026. We anticipate that we will have operating losses and net cash outflows in future periods.

We are subject to risks common to biopharmaceutical companies including, but not limited to, development of new drug candidates, dependence on key personnel, commercialization of our drugs 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. To date, we have funded operations primarily through sales of our common stock, contract payments under our collaboration agreements, sales of future revenues and royalties, debt financing arrangements, and interest income, but we will increasingly rely on revenues generated from the commercial sales of MYQORZO to fund our operations and cash expenditures. We commenced commercial sales in the first quarter of 2026, but there can be no assurance as to the timing or level of revenues from such sales. Until we achieve profitable operations, we intend to continue to fund operations through payments from strategic collaborations, additional sales of equity securities, and debt financings in addition to our commercial sales revenue.

Our success is dependent on our ability to obtain additional capital by entering into financings or new strategic collaborations, and ultimately on our and our collaborators’ ability to successfully develop and market our drugs and drug candidates. We cannot be certain that sufficient funds will be available from financings or such collaborators when needed or on satisfactory terms. Additionally, there can be no assurance that MYQORZO or any of our drug candidates will be accepted in the marketplace or that any future products can be developed or manufactured at an acceptable cost. These factors could have a material adverse effect on our future financial results, financial position and cash flows

Based on the current status of our research and development and commercialization activities, we believe that our existing cash, cash equivalents and investments will be sufficient to fund cash requirements for at least the next 12 months after the issuance of this Quarterly Report on Form 10-Q. If, at any time, our prospects for financing our research and development programs decline, we may decide to reduce research and development expenses by delaying, discontinuing or reducing our funding of one or more of our research or development programs. Alternatively, we might raise funds through strategic collaborations, public or private financings or other arrangements. Such funding, if needed, may not be available on favorable terms, or at all. The financial statements do not include any adjustments that might result from the outcome of this uncertainty.

Basis of Presentation

Our condensed consolidated financial statements include the accounts of Cytokinetics and our wholly-owned subsidiaries. The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with GAAP for interim financial information and the instructions to Form 10-Q and Rule 10-01 of Regulation S-X. The financial statements include all adjustments (consisting only of normal recurring adjustments) that management believes are necessary for the fair statement of our financial information. These interim results are not necessarily indicative of results to be expected for the full fiscal year or any future interim period. The balance sheet as of December 31, 2025 has been derived from the audited financial statements at that date but does not include all of the information and footnotes required by GAAP for complete financial statements. The interim condensed financial statements should be read in conjunction with the audited financial statements and notes thereto contained in the Company’s Form 10-K for the year ended December 31, 2025, as filed with the Securities and Exchange Commission.

Reclassification of prior periods

Certain comparative figures have been reclassified to conform to the current period presentation. Specifically, $1.6 million previously reported research and development expenses in the three months ended March 31, 2025 has been reclassified to collaboration cost of revenues. These reclassifications had no effect on the previously reported total assets, total liabilities, or net income.

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Use of Estimates

The preparation of condensed consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosures of contingent assets and liabilities at the date of the condensed consolidated financial statements and the reported amounts of revenues and expenses during the reporting periods. We evaluate our estimates on an ongoing basis. We base our estimates on our historical experience and on assumptions that we believe are reasonable; however, actual results could significantly differ from those estimates.

Net Product Revenue

Our first commercial product MYQORZO® (aficamten), was approved by the FDA in December 2025. MYQORZO is an allosteric and reversible inhibitor of cardiac myosin motor activity. The approval of MYQORZO included a risk evaluation and mitigation strategy (REMS) program intended to support a favorable benefit-risk profile in light of the risk of heart failure due to systolic dysfunction. In patients with oHCM, myosin inhibition with MYQORZO reduces cardiac contractility and left ventricular outflow tract obstruction. The Company enters into agreements with specialty pharmacies and specialty distributors (each a “Customer” and collectively the “Customers”) to sell MYQORZO in the United States. Revenues from product sales are recognized when the Customer obtains control of the Company’s product, which occurs at a point in time, typically upon delivery to the Customer.

Revenue is recorded net of variable consideration, which includes prompt pay discounts, returns, chargebacks, rebates, and co-payment assistance. These deductions to product sales are referred to as gross-to-net deductions and are estimated and recorded in the period in which the related product sales occur. The variable consideration is estimated based on contractual terms as well as management assumptions. The amount of variable consideration is calculated by using the expected value method. Estimates are reviewed quarterly and adjusted as necessary. Taxes assessed by governmental authorities and collected from customers are excluded from product sales.

Accruals are established for gross to net deductions and actual amounts incurred are offset against applicable accruals. The Company reflects these accruals as either a reduction in the related account receivable from the customer or as an accrued liability, depending on the means by which the deduction is settled. Sales deductions are based on management’s estimates that involve a substantial degree of judgment.

Prompt Pay and Distributor Fees: Customers receive a prompt pay discount for payments made within a contractually agreed number of days before the due date. Customers may receive a contractually agreed upon distribution fee. Both of these discounts are accounted for as a reduction of the transaction price and recorded as a contra receivable.

Returns: We typically permit returns if the product is damaged, defective, or otherwise cannot be used by the customer. We typically permit returns six months prior to and up to one year after the product expiration date. The Company records allowances for product returns as a reduction of revenue at the time product sales are recorded. Product returns are estimated based on industry data. A returns reserve is recorded as an accrued liability.

Rebates and Chargebacks: Rebates and chargebacks include amounts due to payers and healthcare providers under various programs based on contractual arrangements or statutory requirements, which may vary by payer and individual plans. Providers qualified under certain programs can purchase our products through our specialty pharmacies and distributors at a discount. The specialty pharmacies or distributors then charge the discount back to us.

Rebates and chargebacks are estimated primarily based on product sales, historical and estimated payer mix and discount rates, among other inputs, which require significant estimates and judgment. Since we launched our first commercial product in the first quarter of 2026, we do not have historical data and we are relying on industry information. We assess and update our estimates each reporting period to reflect actual claims and other current information.

Co-Payment Assistance: Co-payment assistance programs are offered to eligible end-users as price concessions and are recorded as accrued liabilities and a reduction of the transaction price. The Company uses a third-party to administer the co-payment program for pharmacy benefit claims. Our accrual for co-pay assistance programs is based on an estimate of claims and the cost per claim that we expect to receive associated with inventory that exists in the distribution channel at period end.

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The Company generates revenue from a small number of specialty pharmacies and specialty distributors. The following customers accounted for over 10% of total gross product revenue during the three months ended March 31, 2026. As the Company launched MYQORZO in January 2026, there were no sales in prior periods.

|  | Three Months Ended |  |
|  | March 31, 2026 |  |  | March 31, 2025 |  |
Customer A |  |  | 45 | % |  |  | 0 | % |
Customer B |  |  | 31 | % |  |  | 0 | % |
Customer C |  |  | 24 | % |  |  | 0 | % |

Accounts Receivable, net

The Company's trade accounts receivable arise from product sales and represent amounts due from its customers. In addition, the Company records accounts receivable arising from its collaboration and licensing agreements. The Company provides allowances against receivables for estimated losses, if any, that may result from a counterparty's inability to pay. Amounts determined to be uncollectible are written-off against the allowance.

Inventories

Inventories, which consist of raw materials, work in process and finished goods, are stated at the lower of cost or estimated net realizable value, using standard costs, based on a first-in, first-out method. We have entered into manufacturing and supply agreements for the manufacture or purchase of raw materials and production supplies in prior years. Our inventories include the direct purchase cost of materials and supplies, charges from contract manufacturing organizations and manufacturing overhead costs. We will periodically review our inventories for factors that could impact the future recoverability and realization of future sales, which require estimates and judgments. We will analyze our inventory levels quarterly and write down inventories subject to expiry, in excess of expected requirements or that has a cost basis in excess of its expected net realizable value. These write downs will be charged to cost of sales in the accompanying consolidated statements of operations and comprehensive loss.

We received FDA approval for MYQORZO on December 19, 2025 and began capitalizing inventories upon FDA approval. Costs incurred prior to approval have been recorded as research and development expense in our consolidated statement of operations and comprehensive loss. As a result, inventory balances and cost of sales for the next several quarters are expected to reflect a lower average per unit cost of materials.

Note 2 — Net Loss Per Share

The following instruments were excluded from the computation of diluted net loss per share for the periods presented because their effect would have been antidilutive (in thousands):

|  | March 31, 2026 |  |  | March 31, 2025 |
Options to purchase common stock |  |  | 11,783 |  |  |  | 11,714 |
Restricted stock and performance units |  |  | 3,085 |  |  |  | 2,498 |
Shares issuable related to the ESPP |  |  | 55 |  |  |  | 66 |
Shares issuable upon conversion of 2026 Notes |  |  | 2,003 |  |  |  | 2,003 |
Shares issuable upon conversion of 2027 Notes |  |  | 2,751 |  |  |  | 10,572 |
Shares issuable upon conversion of 2031 Notes |  |  | 10,962 |  |  |  | — |
Total shares |  |  | 30,639 |  |  |  | 26,853 |

Note 3 — Agreements with Royalty Pharma

On January 7, 2022, we entered into the 2022 RPI Transactions with affiliates of Royalty Pharma International plc. Pursuant to the 2022 RPI Transactions, the RP Multi Tranche Loan Agreement and the RP Aficamten RPA described below, are determined to be debt instruments subsequently measured at amortized cost and were entered into with parties that were at the time of our entry into the 2022 RPI Transactions affiliated and in contemplation of one another. We used the relative fair value method and made separate estimates of the fair value of each freestanding financial instrument and then allocated the proceeds in proportion to those fair value amounts. Arrangement consideration for the RP Multi Tranche Loan Agreement and the RP Aficamten RPA totaled $150 million, consisting of the two $50 million up front payments for the signing of the RP Multi Tranche Loan Agreement and the RP Aficamten RPA and milestone of $50 million for the initiation of the first pivotal trial in oHCM for aficamten that was deemed probable at the signing of the agreements.

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On May 22, 2024, we entered into the 2024 RPI Transactions with affiliates of Royalty Pharma International plc, which included an amendment to the RP Aficamten RPA, a component of the 2022 RPI Transactions. The 2024 RPI Transactions include the 2024 RP OM Loan Agreement, the RP Ulacamten RPA, the RP Stock Purchase Agreement, the RP Multi Tranche Loan Agreement Amendment and the RP Aficamten RPA Amendment, as described below, are accounted for as a debt modification of the 2022 RPI Transactions.

Liabilities Related to RPI Transactions Measured at Fair Value

As permitted under ASC 825, we elected the fair value option for recognizing the liabilities related to the 2024 RP OM Loan Agreement and the RP Ulacamten RPA. The fair value option was elected because these liabilities included embedded derivatives which would have otherwise required separate recognition and measurement. The Company elected the fair value option as it is believed to be more practical for each liability as a single unit of account at fair value. Under the fair value option, debt issuance costs are expensed as incurred and the Company is required to record the fair value option elected arrangements at their fair value on the date of issuance and at each balance sheet thereafter. Changes in the estimated fair value of the arrangements are recognized as changes in fair value of liabilities related to RPI Transactions in the condensed consolidated statement of operations and comprehensive loss.

Accounting for RPI Transactions Measured at Fair Value

The fair values of the liabilities for the 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 12% to 17% and 12% to 18% as of March 31, 2026 and 2025, respectively), 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 omecamtiv mecarbil or ulacamten programs 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 Company recorded a loss of $1.6 million for the three months ended March 31, 2026, and a gain of $3.9 million for the three months ended March 31, 2025, associated with the change in fair value of the liabilities related to 2024 RP OM Loan Agreement and the RP Ulacamten RPA. The change in the fair value has been recognized in the condensed consolidated statement of operations and comprehensive loss.

The following tables summarize the changes of the fair value of t he RP Ulacamten RPA and RP OM Loan (in thousands):

|  | 2026 |  |  | 2025 |
|  | RP Ulacamten RPA |  |  | RP OM Loan |  |  | RP Ulacamten RPA |  |  | RP OM Loan |
Beginning balance, January 1 |  | $ | 13,700 |  |  | $ | 123,500 |  |  | $ | 14,000 |  |  | $ | 123,000 |
Change in fair value |  |  | (200 | ) |  |  | 1,800 |  |  |  | (300 | ) |  |  | (3,600 | )
Ending balance, March 31 |  | $ | 13,500 |  |  | $ | 125,300 |  |  | $ | 13,700 |  |  | $ | 119,400 |

Liabilities Related to Revenue Participation Right Purchase Agreements

RP Aficamten Royalty Purchase Agreement

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. In the second quarter of 2024, we recorded an additional $33.3 million to the carrying value related to the 2024 RPI Transactions entered into May 22, 2024. The imputed rate of interest on the carrying value of the RP Aficamten Liability was approximately 26.0% as of March 31, 2026 and 23.5% as of March 31, 2025.

2017 RP Omecamtiv Mecarbil Royalty Purchase Agreement

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 March 31, 2026 and March 31, 2025.

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Accounting for Revenue Participation Right Purchase Agreements

We periodically assess the amount and timing of expected royalty payments using a combination of internal projections and forecasts from external sources. The RP OM Liability and the RP Aficamten Liability are measured using the effective interest method based on estimates of future royalty payments over the life of the arrangements. To the extent such payments are greater or less than our initial estimates or the timing of such payments is materially different than its original estimates, we will prospectively adjust the amortization of the RP OM Liability and the RP Aficamten Liability and the effective interest rate. A significant change to unobservable inputs could also result in a material increase or decrease to the effective interest rate of the liabilities. Note, for the RP OM Liability, the effective interest rate is reassessed periodically and will not be reduced below 0%.

There are a number of factors that could materially affect the amount and timing of royalty payments, a number of which are not within our control. The RP OM Liability and the RP Aficamten Liability are recognized using significant unobservable inputs. The estimates of future royalties require the use of several assumptions such as: the probability of clinical success, the probability of regulatory approval, the estimated date of a product launch, estimates of eligible patient populations, estimates of prescribing behavior and patient compliance behavior, estimates of pricing, payor reimbursement and coverage, and sales ramp. A significant change in unobservable inputs could result in a material increase or decrease to the effective interest rate of the RP OM Liability and the RP Aficamten Liability.

We review our assumptions on a regular basis and our estimates may change in the future as we refine and reassess our assumptions. Changes to the RP Aficamten Liability and the RP OM Liability are as follows (in thousands):

|  | 2026 |  |  | 2025 |
|  | RP Aficamten Liability |  |  | RP OM Liability |  |  | RP Aficamten Liability |  |  | RP OM Liability |
Beginning balance, January 1 |  | $ | 320,764 |  |  | $ | 199,795 |  |  | $ | 262,599 |  |  | $ | 199,593 |
Interest accretion |  |  | 18,816 |  |  |  | — |  |  |  | 14,037 |  |  |  | 41 |
Amortization of issuance costs |  |  | — |  |  |  | — |  |  |  | — |  |  |  | 26 |
Ending balance, March 31 |  | $ | 339,580 |  |  | $ | 199,795 |  |  | $ | 276,636 |  |  | $ | 199,660 |

RP Multi Tranche Term Loan

Tranche 7 under the RP Multi Tranche Loan Agreement Amendment for $175.0 million is drawable at Cytokinetics’ discretion within one year of FDA approval of aficamten in oHCM.

As of March 31, 2026, the estimated fair value of the Tranche 1, Tranche 4, Tranche 5, and Tranche 6 term loans was $277.3 million. The fair value was estimated based on Level 3 inputs.

Derivative Liabilities Measured at Fair Value

We have bifurcated and recognized the embedded derivatives in the RP Multi Tranche Loan Agreement. These embedded derivatives include repayment features based upon a change in control.

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 12% to 13% for the three months ended March 31, 2026 and 12% to 14% for the three months ended March 31, 2025) and other factors.

The following table summarizes the changes of the fair value of the derivative liabilities for the RP Multi Tranche Loan Agreement (in thousands):

|  | RP Multi Tranche Loan Agreement Derivatives |
|  | 2026 |  |  | 2025 |
Beginning balance, January 1 |  | $ | 31,100 |  |  | $ | 11,300 |
Change in fair value |  |  | (1,500 | ) |  |  | 400 |
Ending balance, March 31 |  | $ | 29,600 |  |  | $ | 11,700 |

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Note 4 — Research and Development Arrangements

Collaboration for Commercialization of Aficamten in Greater China

Effective December 17, 2024, Sanofi has an exclusive license to develop and commercialize aficamten in China and Taiwan (the "Sanofi License Agreement"). The total maximum development and commercial milestone payments achievable for development and commercial milestone events in the field of oHCM and nHCM are $160.0 million, of which we have already earned $10.0 million in 2024 and $15.0 million in 2025, following regulatory approval of MYQORZO by the National Medical Products Administration ("NMPA") in China and the FDA in the United States. We are also entitled to receive tiered royalties in the low-to-high teens range on the net sales of pharmaceutical products containing aficamten in China and Taiwan, subject to certain reductions for generic competition, patent expiration and payments for licenses to third party patents.

The Sanofi License Agreement will, unless terminated earlier, continue on a market-by-market basis until expiration of the relevant royalty term.

Collaboration revenues for China were $0.5 million and $0.1 million for the three months ended March 31, 2026 and 2025, respectively, related to certain development cost reimbursements. Accounts receivable from Sanofi was $0.2 million as of March 31, 2026 and $15.1 million as of December 31, 2025.

Collaboration for Commercialization of Aficamten in Japan

On November 19, 2024, we announced that we had entered into a collaboration and license agreement with Bayer Consumer Care AG, an affiliate of Bayer AG, for the exclusive development and commercialization of aficamten in Japan, subject to certain reserved development rights of Cytokinetics to continue to conduct certain clinical trials (the "Bayer License Agreement").

License and milestone revenues from Bayer was $11.9 million for the three months ended March 31, 2026. The amount recognized in the current period relates to the milestone achievement of the first commercial sale of MYQORZO in the United States. Milestones associated with the first dosing of aficamten to the first patient in Japan in a Phase 3 clinical trial in nHCM and in a Phase 3 clinical trial in oHCM were achieved in 2025 and recognized as revenue in 2025. The first dose of aficamten in Japan in a Phase 3 clinical trial in nHCM occurred in June 2025 and the first dose of aficamten in Japan in a Phase 3 clinical trial in oHCM occurred in August 2025. There are no outstanding receivables related to license and milestone revenues from Bayer as of March 31, 2026.

Collaboration revenues from Bayer were $2.1 million and $1.4 million for the three months ended March 31, 2026 and 2025, respectively, related to certain research and development cost reimbursements. We had accounts receivable from Bayer of $2.1 million as of March 31, 2026, and $2.6 million as of December 31, 2025.

We re-evaluate the probability of achievement of development milestones and any related constraints each reporting period. We will include consideration, without constraint, in the transaction price to the extent it is probable that a significant reversal in the amount of cumulative revenue recognized will not occur.

Research Collaboration

In May 2025, we entered into a research collaboration where we will reimburse our collaborative research partner for their research expenses. The reimbursement of research expenses was $1.2 million for the three months ended March 31, 2026 which was recorded as research and development. Subject to the terms of the agreement, our collaborative research partner may receive potential research, development and commercial milestone and royalty payments from us and we may develop and commercialize development candidates.

Note 5 — Fair Value Measurements

We value our financial assets and liabilities at fair value, defined as the price that would be received for assets when sold or paid to transfer a liability in an orderly transaction between market participants at the measurement date (exit price). We utilize market data or assumptions that we believe market participants would use in pricing the asset or liability, including assumptions about risk and the risks inherent in the inputs to the valuation technique. These inputs can be readily observable, market corroborated or generally unobservable.

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We primarily apply the market approach for recurring fair value measurements and endeavor to utilize the best information reasonably available. Accordingly, we use valuation techniques that maximize the use of observable inputs and minimize the use of unobservable inputs to the extent possible and consider the security issuers’ and the third-party issuers’ credit risk in our assessment of fair value.

We classify fair value based on the observability of those inputs using a hierarchy that prioritizes the inputs used to measure fair value. The hierarchy gives the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities (Level 1 measurement) and the lowest priority to unobservable inputs (Level 3 measurement):

Level 1 — Observable inputs, such as quoted prices in active markets for identical assets or liabilities;

Level 2 — Inputs, other than the quoted prices in active markets, that are observable either directly or through corroboration with observable market data; and

Level 3 — Unobservable inputs, for which there is little or no market data for the assets or liabilities, such as internally-developed valuation models.

Fair Value of Financial Assets:

The following tables set forth the fair value of our financial assets, which consists of cash equivalents and investments classified as available-for-sale securities, that were measured on a recurring basis (in thousands):

|  |  |  | March 31, 2026 |
|  | Fair Value Hierarchy Level |  | Amortized Cost |  |  | Unrealized Gains |  |  | Unrealized Losses |  |  | Fair Value |
Money market funds |  | Level 1 |  | $ | 65,528 |  |  | $ | — |  |  | $ | — |  |  | $ | 65,528 |
U.S. Treasury securities |  | Level 1 |  |  | 203,112 |  |  |  | 196 |  |  |  | (31 | ) |  |  | 203,277 |
U.S. Government agency securities |  | Level 2 |  |  | 208,017 |  |  |  | 29 |  |  |  | (316 | ) |  |  | 207,730 |
Commercial paper |  | Level 2 |  |  | 203,988 |  |  |  | 6 |  |  |  | (130 | ) |  |  | 203,864 |
Asset-backed securities |  | Level 2 |  |  | 7,633 |  |  |  | — |  |  |  | (2 | ) |  |  | 7,631 |
Corporate obligations |  | Level 2 |  |  | 322,585 |  |  |  | 121 |  |  |  | (539 | ) |  |  | 322,167 |
|  |  |  | $ | 1,010,863 |  |  | $ | 352 |  |  | $ | (1,018 | ) |  | $ | 1,010,197 |

|  |  |  | December 31, 2025 |
|  | Fair Value Hierarchy Level |  | Amortized Cost |  |  | Unrealized Gains |  |  | Unrealized Losses |  |  | Fair Value |
Money market funds |  | Level 1 |  | $ | 89,509 |  |  | $ | — |  |  | $ | — |  |  | $ | 89,509 |
U.S. Treasury securities |  | Level 1 |  |  | 239,097 |  |  |  | 574 |  |  |  | (7 | ) |  |  | 239,664 |
U.S. Government agency securities |  | Level 2 |  |  | 201,788 |  |  |  | 162 |  |  |  | (38 | ) |  |  | 201,912 |
Commercial paper |  | Level 2 |  |  | 289,447 |  |  |  | 96 |  |  |  | (26 | ) |  |  | 289,517 |
Asset-backed securities |  | Level 2 |  |  | 7,579 |  |  |  | 7 |  |  |  | — |  |  |  | 7,586 |
Corporate obligations |  | Level 2 |  |  | 363,645 |  |  |  | 457 |  |  |  | (53 | ) |  |  | 364,049 |
|  |  |  | $ | 1,191,065 |  |  | $ | 1,296 |  |  | $ | (124 | ) |  | $ | 1,192,237 |

Investments in corporate debt securities, commercial paper, asset-backed securities and U.S. Government agency securities are classified as Level 2 as they are valued based upon quoted market prices for similar instruments in active markets, quoted prices for identical or similar instruments in markets that are not active and model-based valuation techniques for which all significant inputs are observable in the market or can be corroborated by observable market data for substantially the full term of the assets. Where applicable, these models project future cash flows and discount the future amounts to a present value using market-based observable inputs obtained from various third-party data providers, including but not limited to benchmark yields, interest rate curves, reported trades, broker/dealer quotes and reference data.

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No credit losses on debt securities were recognized in the periods presented. In its evaluation to determine expected credit losses, management considered all available historical and current information, expectations of future economic conditions, the type of security, the credit rating of the security, and the size of the loss position, as well as other relevant information. The unrealized losses as of March 31, 2026 are attributed to market interest rate changes and are not attributed to credit. The Company does not intend to sell any of these available-for-sale investments before their effective maturity or market price recovery.

Note 6 — Balance Sheet Components

Cash, cash equivalents, and restricted cash

A reconciliation of cash, cash equivalents, and restricted cash reported in the accompanying condensed consolidated balance sheets to the amount reported within the accompanying condensed consolidated statements of cash flows was as follows (in thousands):

|  | March 31, 2026 |  |  | December 31, 2025 |
Cash and cash equivalents |  | $ | 129,843 |  |  | $ | 122,518 |
Restricted cash |  |  | 3,111 |  |  |  | 3,114 |
Total cash, cash equivalents, and restricted cash as reported within our condensed consolidated statement of cash flows |  | $ | 132,954 |  |  | $ | 125,632 |

As of March 31, 2026, our restricted cash balance of $3.1 million is used to collateralize certain credit instruments.

Accounts receivable, net

Accounts receivable, net was as follows (in thousands):

|  | March 31, 2026 |  |  | December 31, 2025 |
Accounts receivable, net: |  |  |  |  |  |
Net product receivables |  | $ | 4,473 |  |  | $ | — |
Collaboration receivables |  |  | 2,354 |  |  |  | 17,764 |
Total accounts receivable, net |  | $ | 6,827 |  |  | $ | 17,764 |

Inventories

Inventories were as follows (in thousands):

|  | March 31, 2026 |  |  | December 31, 2025 |
Inventories: |  |  |  |  |  |
Finished goods |  | $ | 154 |  |  | $ | — |
Total inventories, current |  |  | 154 |  |  |  | — |
Inventories, long-term (1) |  |  | 3,843 |  |  |  | — |
Total current and long-term inventories |  | $ | 3,997 |  |  | $ | — |

(1) Inventories, long-term, are comprised of raw materials and work in process that are expected to be sold beyond the next 12 months.

Accrued liabilities

Accrued liabilities were as follows (in thousands):

|  | March 31, 2026 |  |  | December 31, 2025 |
Accrued liabilities: |  |  |  |  |  |
Clinical and preclinical costs |  | $ | 23,981 |  |  | $ | 24,561 |
Compensation related |  |  | 27,355 |  |  |  | 45,150 |
Other accrued expenses |  |  | 17,527 |  |  |  | 13,567 |
Total accrued liabilities |  | $ | 68,863 |  |  | $ | 83,278 |

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Note 7 — Debt

Convertible Notes

2031 Notes

The following table presents the total amo unt of interest cost recognized relating to the 2031 Notes (in thousands):

|  | Three Months Ended |
|  | March 31, 2026 |  |  | March 31, 2025 |
Contractual interest expense |  | $ | 3,281 |  |  | $ | — |
Amortization of debt issuance costs |  |  | 746 |  |  |  | — |
Total interest expense recognized |  | $ | 4,027 |  |  | $ | — |

The effective interest rate of the 2031 Notes was 2.23% as of March 31, 2026. As of March 31, 2026, the unamortized debt issuance cost for the 2031 Notes was $18.8 million and will be amortized over approximately 5.6 years.

2027 Notes

The following table presents the total amo unt of interest cost recognized relating to the 2027 Notes (in thousands):

|  | Three Months Ended |
|  | March 31, 2026 |  |  | March 31, 2025 |
Contractual interest expense |  | $ | 1,230 |  |  | $ | 4,726 |
Amortization of debt issuance costs |  |  | 204 |  |  |  | 746 |
Total interest expense recognized |  | $ | 1,434 |  |  | $ | 5,472 |

The effective interest rate of the 2027 Notes was 4.2% as of March 31, 2026 and 2025. As of March 31, 2026, the unamortized debt issuance cost for the 2027 Notes was $1.2 million and will be amortized over approximately 1.3 years. During the three months ended March 31, 2026, the conditions allowing holders of the 2027 Notes to convert were not met. As a result, the 2027 Notes are not convertible as of March 31, 2026.

2026 Notes

The following table presents the total amo unt of interest cost recognized relating to the 2026 Notes (in thousands):

|  | Three Months Ended |
|  | March 31, 2026 |  |  | March 31, 2025 |
Contractual interest expense |  | $ | 211 |  |  | $ | 211 |
Amortization of debt issuance costs |  |  | 27 |  |  |  | 26 |
Total interest expense recognized |  | $ | 238 |  |  | $ | 237 |

The effective interest rate of the 2026 Notes was 4.6% as of March 31, 2026 and 2025. As of March 31, 2026, the unamortized debt issuance cost for the 2026 Notes was $0.1 million and will be amortized over approximately 0.6 years. The 2026 Notes are convertible at March 31, 2026 at the option of the holder and classified as current on the condensed consolidated balance sheet.

As of March 31, 2026, the estimated fair value of the 2031 Notes, 2027 Notes, and 2026 Notes was $957.1 million, $205.4 million and $132.7 million, respectively, and was based upon observable, Level 2 inputs, including pricing information from recent trades of the Convertible Notes.

Note 8 — Stockholders’ Equity

Equity Incentive Plan

Our 2004 Plan provides for us to grant incentive stock options, non-statutory stock options, restricted stock, stock appreciation rights, restricted stock units, performance shares and performance units to employees, directors, and consultants. We may grant options for terms of up to ten years at prices not lower than 100% of the fair market value of our common stock on the date of grant. Options granted to new employees generally vest 25% after one year and monthly thereafter over a period of four years. Options granted to existing employees generally vest monthly over a period of four years.

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Our annual grant of stock-based compensation t akes place during the first quarter of each year. Our stock options and restricted stock units granted during the first quarter of 2026 were as follows:

|  | Grants |  |  | Weighted Average Grant Date Fair Value per Share |
Stock options |  |  | 1,518,443 |  |  | $ | 60.20 |
Restricted stock units |  |  | 1,460,603 |  |  | $ | 60.16 |

As of March 31, 2026, the total authorized shares under the 2004 Plan available for grant was 3.8 million.

Total stock-based compensation expense was recorded in the condensed consolidated statements of operations and comprehensive loss, and allocated as follows (in thousands):

|  | Three Months Ended |  |
|  | March 31, 2026 |  |  | March 31, 2025 |  |
Research and development |  | $ | 13,581 |  |  | $ | 11,678 |  |
General and administrative |  |  | 16,813 |  |  |  | 11,871 |  |
|  | $ | 30,394 |  |  | $ | 23,549 |  |

For the three months ended March 31, 2026, w e capitalized approximately $0.4 million of stock based compensation into inventories.

Performance Stock Units

During 2025 through the first quarter of 2026, the Compensation Committee granted a total of 756,616 performance stock units ("PSUs") to certain employees with a grant date fair value ranging from $44.36 to $63.75 per unit. The fair value of the PSUs was determined on the grant date based on the fair value of the Company’s common stock at such time. The PSU awards are subject to performance goals and will be earned as to a pre-determined fixed number of shares subject to the certification by the Compensation and Talent Committee of the Company’s Board of Directors (the “Compensation Committee”) that the Company has achieved one or more of the relevant performance goals, in each case vesting as to 50% of the earned shares on applicable Compensation Committee certification date and as to the remaining 50% of the earned shares following the one-year anniversary of the applicable Compensation Committee certification date.

The Company recognized expense for the PSUs of $0.5 million and $1.2 million for the three months ended March 31, 2026 and 2025, respectively. The decrease year over year was due to our Prescription Drug User Fee Act ("PDUFA") target action date for NDA for aficamten in oHCM was extended to December 2025. This resulted in a revision of the PSU assumptions and a reduction of expense that impacted the first quarter of 2026. There was $13.1 million of unamortized stock-based compensation related to the portion of PSUs vesting that is deemed probable as of March 31, 2026.

Controlled Equity Offering Sales Agreement

On February 27, 2025, we entered into an Open Market Sale Agreement SM 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 March 31, 2026, we have not sold any shares of common stock under the Open Market Sale Agreement SM with Jefferies LLC.

Note 9 — Commitments and Contingencies

Legal Matters

From time to time, the Company is a party to legal proceedings in the course of the Company's business. The outcome of such matters is inherently uncertain and often involves significant judgment in assessing risk and estimating potential exposure. Accruals are recognized for legal matters when a loss is both probable and reasonably estimable. As of March 31, 2026, no material contingent liabilities have been recognized. If a material loss is reasonably possible and we can estimate the amount or range of the loss, we disclose such information. Unless otherwise noted, either the outcome of these matters is not expected to be material, or the potential loss cannot be reasonably estimated.

In re Cytokinetics, Incorporated Securities Litigation

On September 17, 2025, a putative stockholder class action lawsuit was filed against the Company and its Chief Executive Officer

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in the United States District Court for the Northern District of California, alleging violations of 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 the Company's common stock between December 27, 2023 and May 6, 2025. The complaint alleges that the Company made materially false and misleading statements regarding the timeline for the NDA regulatory approval process for aficamten and failed to disclose related material risks. The complaint seeks unspecified damages, together with interest, attorneys' fees, and costs.

On December 22, 2025, the Court appointed Gilbert Rosenthal as Lead Plaintiff and approved his selection of Pomerantz LLP as Lead Counsel. The action is now captioned In re Cytokinetics, Incorporated Securities Litigation, Case No. 3:25-cv-07923-RFL. On March 10, 2026, Lead Plaintiff filed an amended complaint, which, among other things, added the Company's Chief Financial Officer as a defendant. The Company expects to file a motion to dismiss the amended complaint within 60 days of its filing.

The Company and the individual defendants dispute the allegations in the amended complaint and intend to vigorously defend against the action.

Pohlmann v. Blum, et al.

On March 9, 2026, a purported stockholder derivative action captioned Pohlmann v. Blum, et al., Case No. 3:26-cv-01998-RFL, was filed in the United States District Court for the Northern District of California against certain of the Company's current and former directors and its Chief Executive Officer, with the Company named as a nominal defendant. The complaint asserts claims for breach of fiduciary duty, aiding and abetting breach of fiduciary duty, unjust enrichment, waste of corporate assets, contribution under the Securities Exchange Act of 1934, and violations of Section 14(a) of the Securities Exchange Act of 1934 and Rule 14a-9 promulgated thereunder. The allegations are based substantially on the same underlying facts and circumstances as those alleged in In re Cytokinetics, Incorporated Securities Litigation and principally concern statements regarding the Company's New Drug Application for aficamten and the subsequent extension of the related PDUFA action date. The complaint seeks, among other relief, unspecified damages on behalf of the Company, disgorgement, corporate governance reforms, and attorneys' fees and costs.

On March 27, 2026, the Court found the derivative action to be related to In re Cytokinetics, Incorporated Securities Litigation and reassigned the matter accordingly. On April 16, 2026, the Court entered an order, pursuant to the parties' stipulation, staying the derivative action in its entirety during the pendency of any motion to dismiss in the securities class action, subject to customary terms.

The Company and the individual defendants dispute the allegations in the derivative action and intend to vigorously defend against the matter.

Other Commitment

We have approximately $17.2 million of non-cancellable commitments related to purchases of materials and inventory manufacturing agreements.

Note 10 — Subsequent Events

On May 5, 2026, we announced positive topline results from ACACIA-HCM, the pivotal Phase 3 clinical trial of aficamten in patients with symptomatic nHCM. ACACIA-HCM met both dual primary endpoints, demonstrating statistically significant improvements from baseline to Week 36 compared to placebo in both Kansas City Cardiomyopathy Questionnaire Clinical Summary Score (KCCQ-CSS) and maximal exercise performance (peak VO2). Statistically significant (p<0.001) improvements compared to placebo were observed in key secondary endpoints including the proportion of participants with improvements in NYHA Functional Class, the composite z-score of ventilatory efficiency and pVO2, and NT-proBNP.

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ITEM 2. 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.

This report contains forward-looking statements indicating expectations about future performance and other forward-looking statements within the meaning of Section 27A of the Securities Act, Section 21E of the Exchange Act, and the Private Securities Litigation Reform Act of 1995, that involve risks and uncertainties. All statements other than statements of historical fact, including statements concerning our plans, objectives, goals, strategies, future events, future revenues or performance, financing needs, expectations, plans or intentions relating to clinical development, product candidates, the regulatory approval process, our commercialization efforts for MYQORZO, products and markets, and business trends and other information referred to under the “Risk Factors” and “Management’s Discussion and Analysis of Financial Condition and Results of Operations,” are forward-looking statements. In some cases, you can identify forward-looking statements by terms such as “anticipate,” “assume,” “believe,” “commitment,” “could,” “estimate,” “expect,” “forecast,” “intend,” “may,” “plan,” “potential,” “predict,” “project,” “should,” “target,” “will,” “would,” “seek” and similar expressions intended to identify forward-looking statements. We have made these statements in reliance on the safe harbor provisions of the Private Securities Litigation Reform Act of 1995. Forward-looking statements are subject to certain risks and uncertainties, which could cause actual results, outcomes, and the timing of events to differ materially from the results discussed in the forward-looking statements.

In addition, these forward-looking statements are subject to the risks and uncertainties discussed in the “Risk Factors” section and elsewhere in this document. Such statements speak only as of the date on which they are made, and, except as required by law, we undertake no obligation to update any forward-looking statement to reflect events or circumstances after the date on which the statement is made or to reflect the occurrence of unanticipated events. New factors emerge from time to time, and it is not possible for us to predict which factors will arise. In addition, we cannot assess the impact of each factor on our business or the extent to which any factor, or combination of factors, may cause actual results to differ materially from those contained in any forward-looking statements.

In addition, statements that “we believe” and similar statements reflect our beliefs and opinions on the relevant subject. These statements are based upon information available to us as of the date of this Quarterly Report on Form 10-Q, and while we believe such information forms a reasonable basis for such statements, such information may be limited or incomplete, and our statements should not be read to indicate that we have conducted an exhaustive inquiry into, or review of, all potentially available relevant information. These statements are inherently uncertain and investors are cautioned not to unduly rely upon these statements.

Overview

We are a biopharmaceutical company focused on discovering, developing and commercializing novel muscle activators and muscle inhibitors as potential treatments for debilitating diseases in which muscle performance is compromised and/or declining. We have discovered and are developing muscle-directed investigational medicines that may potentially improve the health span of people with devastating cardiovascular and neuromuscular diseases of impaired muscle function. Our first commercial product is MYQORZO® (aficamten), 5 mg, 10 mg, 15 mg, and 20 mg tablets, which the FDA approved in December 2025. MYQORZO is an allosteric and reversible inhibitor of cardiac myosin motor activity. The approval of MYQORZO included a risk evaluation and mitigation strategy program, otherwise known as a REMS, intended to support a favorable benefit-risk profile in light of the risk of heart failure due to systolic dysfunction. In patients with oHCM, myosin inhibition with MYQORZO reduces cardiac contractility and left ventricular outflow tract obstruction. MYQORZO became available for prescription to patients on or around January 27, 2026. In addition, in February 2026, the European Commission approved MYQORZO® (aficamten), 5 mg, 10 mg, 15 mg and 20 mg tablets for the treatment of symptomatic (New York Heart Association, NYHA, class II-III) oHCM in adult patients. Moreover, in December 2025, the China National Medical Products Administration approved MYQORZO for the treatment of adults with (New York Heart Association class II-III) oHCM, to improve exercise capacity and symptoms.

Behind MYQORZO, we are making disciplined pipeline investments in investigational products that are at discovery, preclinical and clinical stages of research and development. All our research and development activities relate to the biology of muscle function and have evolved from our knowledge and expertise regarding the cytoskeleton, a complex biological infrastructure that plays a fundamental role within every human cell. As a leader in muscle biology and the mechanics of muscle performance, we are discovering and developing small molecule drug candidates specifically engineered to impact muscle function and contractility with the objective of building a sustainable specialty biopharmaceutical business.

Our specific focus on the biology of the cytoskeleton distinguishes us from other biopharmaceutical companies and potentially positions us to identify or discover and develop and commercialize novel therapeutics that may be useful for the treatment of severe diseases and medical conditions. We intend to leverage our experience in muscle contractility to expand our current pipeline and expect to identify additional potential drug candidates that may be suitable for clinical development and commercialization.

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Cytokinetics’ Marketed Product: MYQORZO®

MYQORZO® (aficamten), is a novel, oral, small molecule cardiac myosin inhibitor that our scientists discovered for the treatment of symptomatic oHCM. MYQORZO was designed to reduce the hypercontractility associated with HCM. In preclinical models, MYQORZO reduces myocardial contractility by binding directly to cardiac myosin at a distinct and selective allosteric binding site, thereby preventing myosin from entering a force producing state. MYQORZO reduces the number of active actin-myosin cross bridges during each cardiac cycle and consequently reduces myocardial contractility.

HCM is the most common monogenic inherited cardiovascular disorder, with well over 300,000 patients diagnosed in the U.S. However, there are an estimated 400,000-800,000 additional patients who remain undiagnosed. The diagnosis rate for oHCM is growing at approximately the same rate as the population, while the diagnosis rate for nHCM has been increasing with recent year-over-year growth estimated to be in the low double digits. Estimates vary but we believe approximately half of patients with HCM have oHCM, in which the thickening of the cardiac muscle leads to LVOT obstruction, while the remaining HCM patients have nHCM, in which blood flow is not impacted, but the heart muscle is still thickened. HCM is fairly evenly split across gender and while patients are typically diagnosed in their early 40s, the average age of an oHCM patient is in the early 60s. People with HCM are at high risk of also developing cardiovascular complications, including atrial fibrillation, stroke and mitral valve disease. People with HCM are at risk for potentially fatal ventricular arrhythmias, and HCM is one of the leading causes of sudden cardiac death in younger people or athletes. A subset of patients with HCM are at high risk of progressive disease leading to dilated cardiomyopathy and heart failure necessitating cardiac transplantation.

In December 2025, the FDA approved MYQORZO, 5 mg, 10 mg, 15 mg, and 20 mg tablets for the treatment of adults with symptomatic oHCM to improve functional capacity and symptoms. MYQORZO is an allosteric and reversible inhibitor of cardiac myosin motor activity. The approval of MYQORZO included a risk evaluation and mitigation strategy (REMS) program intended to support a favorable benefit-risk profile in light of the risk of heart failure due to systolic dysfunction. In addition, in February 2026, the European Commission approved MYQORZO® (aficamten), 5 mg, 10 mg, 15 mg and 20 mg tablets for the treatment of symptomatic (New York Heart Association, NYHA, class II-III) obstructive hypertrophic cardiomyopathy (oHCM) in adult patients. Moreover, in December 2025, the China National Medical Products Administration approved MYQORZO for the treatment of adults with (New York Heart Association class II-III) oHCM, to improve exercise capacity and symptoms.

We commenced commercial sales of MYQORZO in the United States in the first quarter of 2026. Our market research supports our belief that MYQORZO will be highly competitive amongst cardiac myosin inhibitors, potentially eventually achieving a greater than 50% market share in the United States but also growing the cardiac myosin inhibitor category overall. Our partner, Sanofi, also commenced commercialization activities in China in the first quarter of 2026.

The commercial prospects for MYQORZO depend on three launch drivers: clinical evidence, our experience with HCPs and patients, and the approved label. Clinical evidence shows that treatment with MYQORZO in adult patients with symptomatic oHCM led to rapid and sustained reduction in obstruction and improvement in symptoms. Our experience with HCPs and patients informed our Cardiac Account Specialist (CAS) design, including its single point of contact and accountability for HCP's with our field sales organization and our bespoke patient support program, MYQORZO and You™.

We believe the MYQORZO prescribing information allows for flexibility to titrate as early as two weeks, with echo assessment within 2 to 8 weeks following dose initiation and any subsequent dose changes, and importantly, a patient's dose may be titrated as needed after each echo with no delay.

In the European Union, we anticipate commencing commercialization activities in Germany in the second quarter of 2026 to be followed by other major European countries. MYQORZO is approved in China for the treatment of adults with (New York Heart Association class II-III) oHCM, to improve exercise capacity and symptoms. We depend on Sanofi for commercialization of MYQORZO in China.

Finally, in January 2026 we submitted, and the FDA subsequently accepted for filing, a supplemental NDA for MYQORZO to the FDA requesting to include the results of MAPLE-HCM, a Phase 3 randomized, double blind, active-comparator clinical trial of aficamten as monotherapy compared to metoprolol as a monotherapy in patients with obstructive HCM, in the label. The FDA assigned a standard review classification to the sNDA with a PDUFA date of November 14, 2026.

Research and Development Programs

Our research and development activities related to muscle contractility include our cardiac muscle contractility programs and our skeletal muscle contractility programs. We also conduct research and development on novel treatments for disorders involving muscle function beyond muscle contractility.

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Specialty Cardiology Programs

Our specialty cardiology program is focused on the cardiac sarcomere, the basic unit of muscle contraction in the heart. The cardiac sarcomere is a highly ordered cytoskeletal structure composed of cardiac myosin, actin and a set of regulatory proteins. Cardiac myosin is the cytoskeletal motor protein in the cardiac muscle cell. It is directly responsible for converting chemical energy into the mechanical force, resulting in cardiac muscle contraction. Our most advanced cardiac program, MYQORZO (aficamten), is based on the hypothesis that inhibitors of cardiac myosin may attenuate the hyperdynamic contraction resulting from pathologic mutations in the sarcomere that lead to hypertrophic cardiomyopathies. MYQORZO was approved in the U.S., Europe and China for the treatment of adults with symptomatic oHCM. We submitted a supplemental NDA to the FDA in January 2026 with the intent to include the results of MAPLE-HCM (a Phase 3 randomized, double blind, active-comparator clinical trial of aficamten as monotherapy compared to metoprolol as a monotherapy in patients with obstructive HCM) in the label. Finally, as described below, we evaluated aficamten for the potential treatment of adults with symptomatic nHCM in ACACIA-HCM.

In addition, omecamtiv mecarbil is our late-stage clinical program directed to the hypothesis that activators of cardiac myosin may target the underlying deficit of cardiac contractility in heart failure with severely reduced ejection fraction and address certain adverse properties of existing positive inotropic agents. Omecamtiv mecarbil is a novel cardiac myosin activator that works by directly stimulating the activity of the cardiac myosin motor protein, without increasing the intracellular calcium concentration. This drug candidate accelerates the rate-limiting step of the myosin enzymatic cycle and shifts it in favor of the force-producing state. Rather than increasing the velocity of cardiac contraction, this mechanism lengthens the systolic ejection time, which results in increased cardiac function in a potentially more oxygen-efficient manner.

Aficamten

Aficamten is a novel, oral, small molecule cardiac myosin inhibitor that our scientists discovered for the treatment of HCM. Aficamten arose from an extensive chemical optimization program conducted with attention to therapeutic index and pharmacokinetic properties. Aficamten was designed to reduce the hypercontractility associated with HCM. In preclinical models, aficamten reduces myocardial contractility by binding directly to cardiac myosin at a distinct and selective allosteric binding site, thereby preventing myosin from entering a force producing state. Aficamten reduces the number of active actin-myosin cross bridges during each cardiac cycle and consequently reduces myocardial contractility. This mechanism of action may be therapeutically effective in conditions characterized by excessive hypercontractility, such as HCM. The preclinical pharmacokinetics of aficamten were characterized, evaluated and optimized for potential rapid onset, ease of titration and rapid symptom relief.

The FDA granted aficamten orphan drug designation for the treatment of symptomatic HCM in 2021.

The development program for aficamten has assessed its potential as a treatment to improve exercise capacity and relieve symptoms in patients with oHCM. In addition, development work is ongoing to assess aficamten for its potential long-term effects on cardiac structure and function.

Aficamten was evaluated in SEQUOIA-HCM, a positive pivotal Phase 3 clinical trial in patients with symptomatic oHCM. The results from SEQUOIA-HCM showed that treatment with aficamten for 24 weeks significantly improved exercise capacity compared to placebo, increasing peak oxygen uptake (pVO2) by 1.8 ml/kg/min compared to baseline in patients treated with aficamten versus 0.0 ml/kg/min in patients treated with placebo (p=0.000002). This treatment effect was consistent across all pre-specified subgroups, including patients receiving beta blockers. Statistically significant and clinically meaningful improvements were also observed in all 10 prespecified secondary endpoints, with functional and symptomatic improvements occurring within two weeks of initiating treatment with aficamten and sustained throughout the treatment period. There were no instances of worsening heart failure and no treatment interruptions due to low LVEF. Treatment emergent serious adverse events occurred in 5.6% of patients on MYQORZO (aficamten) and 9.3% of patients on placebo. Core laboratory echocardiographic LVEF was observed to be <50% in 5 patients (3.5%) on MYQORZO compared to 1 patient (0.7%) on placebo. Hypertension (8% vs 2%) was the only adverse reaction occurring in >5% of patients and more commonly on MYQORZO than on placebo. MYQORZO-associated increases in blood pressure are consistent with relief of LVOT obstruction and improved cardiac output. MYQORZO has been approved in the United States, the European Union, and China and, in each case as a treatment for adults with symptomatic oHCM.

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Aficamten was also evaluated in MAPLE-HCM, a Phase 3 randomized, double blind, active-comparator clinical trial of aficamten as monotherapy compared to metoprolol as a monotherapy in patients with obstructive HCM. In May 2025, the company announced positive topline results from MAPLE-HCM and in August 2025 the company presented the primary results of MAPLE-HCM at the European Society of Cardiology Congress 2025. The primary endpoint in MAPLE-HCM was the mean change from baseline in pVO 2 for aficamten compared to metoprolol after 24 weeks of treatment. MAPLE-HCM met its primary endpoint, demonstrating a statistically significant improvement in peak oxygen uptake (pVO 2) from baseline to Week 24 for aficamten compared to metoprolol. For aficamten, the mean change in pVO2 from baseline to Week 24 was +1.1 mL/kg/min (95% CI 0.5 to 1.7) and for metoprolol was - 1.2 mL/kg/min (95% CI -1.7 to -0.8). The primary endpoint was statistically significant with a least-squares mean (LSM) difference between groups of 2.3 mL/kg/min (95% CI 1.5 to 3.1; p<0.0001). Overall, the rate of adverse events was similar between groups. At least one treatment-emergent adverse event was reported by 65 (73.9%) and 66 (75.9%) patients treated with aficamten and metoprolol, respectively. One patient receiving aficamten, a 69-year-old woman with multiple co-morbidities, developed a viral illness and subsequently died. Three patients receiving metoprolol terminated treatment due to adverse events. The most common AE reported in excess (>5%) of the comparator was hypertension for aficamten (9 [10.2%] patients compared to 2 [2.3%] patients on metoprolol).

Aficamten was also evaluated in ACACIA-HCM, a Phase 3 randomized, double blind clinical trial in patients with symptomatic nHCM. On May 5, 2026, we announced positive topline results from ACACIA-HCM. ACACIA-HCM met both dual primary endpoints, demonstrating statistically significant improvements from baseline to Week 36 compared to placebo in both Kansas City Cardiomyopathy Questionnaire Clinical Summary Score (KCCQ) and maximal exercise performance (pVO2). The improvement in KCCQ was robust and consistent throughout the treatment period in participants on aficamten. Following washout, KCCQ decreased for participants on aficamten to match the placebo group. At Week 36, pVO2 increased for participants on aficamten, while it remained unchanged for participants on placebo, consistent with prior trials of aficamten in oHCM. Statistically significant (p<0.001) improvements compared to placebo were observed in key secondary endpoints including the proportion of participants with improvements in NYHA Functional Class, the composite z-score of ventilatory efficiency and pVO2, and NT-proBNP. At Week 36, pVO2 increased for participants on aficamten, while it remained unchanged for participants on placebo, consistent with prior trials of aficamten in oHCM. Statistically significant (p<0.001) improvements compared to placebo were observed in key secondary endpoints including the proportion of participants with improvements in NYHA Functional Class, the composite z-score of ventilatory efficiency and pVO2, and NT-proBNP. There were no new safety signals identified. The percentage of participants completing planned dosing was similar in those receiving aficamten or placebo (88.4% vs. 90.3%, respectively). Left ventricular ejection fraction (LVEF) <50% occurred in 27 (10%) participants taking aficamten and 1% in participants taking placebo. Two participants on aficamten experienced a serious adverse event of heart failure associated with LVEF <50%. Treatment interruptions due to LVEF <40% occurred in 3% of participants taking aficamten.

Aficamten continues to be evaluated in CEDAR-HCM, a clinical trial of aficamten in a pediatric population with oHCM; and FOREST-HCM, an open-label extension clinical study of aficamten in patients with HCM. We expect to report complete enrollment in the adolescent cohort of CEDAR-HCM in the fourth quarter of 2026.

Collaboration for Commercialization of Aficamten in Greater China

We are party to a license and collaboration agreement, pursuant to which we granted to Corxel an exclusive license to develop and commercialize drug products containing aficamten in China and Taiwan. In the fourth quarter of 2024, Genzyme Corporation, an affiliate of Sanofi, acquired Corxel's rights to develop and commercialize drug products containing aficamten in China and Taiwan.

The China NMPA approved MYQORZO (aficamten) for the treatment of adults with (NYHA class II-III) oHCM, to improve exercise capacity and symptoms.

Collaboration for Commercialization of Aficamten in Japan

We are party to a collaboration and license agreement with Bayer Consumer Care AG, an affiliate of Bayer AG, for the exclusive development and commercialization of drug products containing aficamten in Japan, subject to certain reserved development rights of Cytokinetics to conduct ACACIA-HCM and CEDAR-HCM in Japan.

The first patient in Japan was dosed in the Japanese cohort of ACACIA-HCM in the second quarter of 2025. The first patient was dosed in Bayer’s Phase 3 clinical trial in oHCM, CAMELLIA-HCM, in Japan in the third quarter of 2025.

Aficamten was recently granted Orphan Drug Designation by the Japan Ministry of Health, Labour and Welfare for patients with nHCM and pediatric patients with oHCM.

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Royalty Pharma Revenue Interest

We are party to a revenue interest agreement with RPI ICAV, the RP Aficamten RPA, pursuant to which RPI ICAV purchased rights to certain revenue streams from net sales of MYQORZO and any other future potential pharmaceutical products containing aficamten by us, our affiliates and our licensees. Pursuant to the terms of the RP Aficamten RPA, as amended, RPI ICAV is entitled to receive 4.5% of our worldwide annual net sales of MYQORZO and any other future potential products containing aficamten up to $5.0 billion and 1% of our annual net sales above $5.0 billion.

Omecamtiv mecarbil

We are developing omecamtiv mecarbil as a potential treatment across the continuum of care in heart failure with severely reduced ejection fraction both for use in the hospital setting and for use in the outpatient setting.

Omecamtiv mecarbil is a selective, small molecule cardiac myosin activator, the first of a novel class of myotropes designed to directly target the contractile mechanisms of the heart, binding to and recruiting more cardiac myosin heads to interact with actin during systole. Omecamtiv mecarbil is designed to increase the number of active actin-myosin cross bridges during each cardiac cycle and consequently augment the impaired contractility that is associated with heart failure with reduced ejection fraction, or HFrEF.

GALACTIC-HF

GALACTIC-HF is a Phase 3 cardiovascular outcomes clinical trial of omecamtiv mecarbil that was conducted by Amgen in collaboration with Cytokinetics. The primary objective of this double-blind, randomized, placebo-controlled multicenter clinical trial was to determine if treatment with omecamtiv mecarbil when added to standard of care is superior to standard of care plus placebo in reducing the risk of cardiovascular death or heart failure events in patients with high-risk chronic heart failure and reduced ejection fraction.

The results of GALACTIC-HF showed a statistically significant effect of treatment with omecamtiv mecarbil to reduce risk of the primary composite endpoint of CV death or heart failure events (heart failure hospitalization and other urgent treatment for heart failure) compared to placebo in patients treated with standard of care after a median duration of follow up of 21.8 months. A first primary endpoint event occurred in 1,523 of 4,120 patients (37.0%) in the omecamtiv mecarbil group and in 1,607 of 4,112 patients (39.1%) in the placebo group (hazard ratio, 0.92; 95% confidence interval [CI] 0.86, 0.99; p=0.025). This effect was observed without evidence of an increase in the overall rates of myocardial ischemic events, ventricular arrhythmias or death from cardiovascular or all causes.

COMET-HF Informed by Results from Patient Subgroup in GALACTIC-HF

Since our release of the primary results of GALACTIC-HF, we have conducted and announced supplemental and subgroup analyses suggesting that certain biologically plausible subgroups of patients treated with omecamtiv mecarbil in GALACTIC-HF may have benefited more than the general patient population in the trial. Based on these and other promising subgroup analyses from GALACTIC-HF and the high unmet need in patients with heart failure with severely reduced ejection fraction, we are continuing the development program for omecamtiv mecarbil and conducting a confirmatory study in a patient population similar to the approximately 4,000 prespecified subgroup of patients with an LVEF <28% in GALACTIC-HF. Accordingly, in the fourth quarter of 2024, we commenced patient enrollment in COMET-HF (Confirmation of Omecamtiv Mecarbil Efficacy Trial in Heart Failure), a Phase 3 multi-center, double-blind, randomized, placebo-controlled trial to assess the efficacy and safety of omecamtiv mecarbil in patients with symptomatic HFrEF with severely reduced ejection fraction. The primary endpoint of COMET-HF is the time to first event in the primary composite endpoint of cardiovascular death, first heart failure event, LVAD implantation or cardiac transplantation, or stroke. COMET-HF is expected to enroll approximately 1,800 patients randomized on a 1:1 basis to receive omecamtiv mecarbil or placebo for up to 48 weeks.

Royalty Pharma Revenue Interest

In 2017, we entered into a Royalty Purchase Agreement, which we refer to as the RP OM RPA, with Royalty Pharma Development Funding, LLC, or RPFT, and amended the RP OM RPA on January 7, 2022. Pursuant to the RP OM RPA, as amended, RPFT has a revenue interest entitling it to up to 5.5% of our affiliates’ and licensees’ worldwide net sales of drug products containing omecamtiv mecarbil.

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In the second quarter of 2024, we entered into the RP OM Loan Agreement with RPDF. Pursuant to the RP OM Loan Agreement, RDPF has a revenue interest entitling it to quarterly payments in an amount equal to 2.0% of the annual worldwide net sales of drug products containing omecamtiv mecarbil, subject to a minimum floor amount ranging from $5.0 million to $8.0 million during the first 18 calendar quarters commencing on the calendar quarter during which FDA approval for any drug product containing omecamtiv mecarbil is obtained, as further described in Note 3 to our condensed consolidated financial statements included in this Annual Report on Form 10-K under the section "Agreements with Royalty Pharma," on the condition that a new Phase 3 clinical trial of omecamtiv mecarbil is successful by June 30, 2028 and we receive the marketing approval from the FDA for omecamtiv mecarbil on or prior to December 31, 2029.

Ulacamten (f/k/a CK-586)

Ulacamten is a novel, selective, oral, small molecule cardiac myosin inhibitor designed to reduce the hypercontractility associated with heart failure with preserved ejection fraction, or HFpEF. Approximately half of the estimated 6.7 million patients in the United States with heart failure have HFpEF, and the prevalence of HFpEF is increasing. A subset of HFpEF patients with hypercontractility, ventricular hypertrophy, elevated biomarkers and symptoms of heart failure may benefit from treatment with a cardiac sarcomere inhibitor. Approximately 75% of patients with HFpEF die within five years of initial hospitalization, and 84% are re-hospitalized. Despite broad use of standard treatments and advances in care, the prognosis for patients with heart failure is poor.

In preclinical models, ulacamten reduced cardiac hypercontractility by decreasing the number of active myosin cross-bridges during cardiac contraction thereby reducing the contractile force, without effect on calcium transients. Ulacamten selectively inhibits the ATPase of intact cardiac myosin but does not inhibit the ATPase of subfragment-1 of myosin (S1) as does aficamten, a cardiac myosin inhibitor we have also developed. Unlike aficamten, the inhibitory effect of ulacamten requires the presence of the regulatory light chain (RLC) of myosin in the context of the intact myosin dimer (heavy meromyosin or HMM). In engineered human HCM heart tissues, ulacamten demonstrated a shallow force-concentration response and improved lusitropy. Lending support for investigating this mechanism of action in HFpEF, a subset of patients with HFpEF resemble patients with non-obstructive hypertrophic cardiomyopathy (HCM) in that those patients have higher ejection fractions, thickened walls of their heart, elevated biomarkers, and symptoms of heart failure. Data from a Phase 2 clinical trial of aficamten in patients with nHCM and the results of ACACIA-HCM show that aficamten was well tolerated, improved patient reported outcomes (Kansas City Cardiomyopathy Questionnaire (KCCQ) and New York Heart Association (NYHA) Functional Class) and biomarkers, measures that are also relevant to HFpEF.

Phase 1 Trial Results

We conducted a Phase 1 double-blind randomized, placebo-controlled, multi-part single and multiple ascending dose clinical study with the goal of evaluating the safety, tolerability and PK of ulacamten when administered orally as single or multiple doses to healthy participants. The primary objective of this clinical study was to evaluate the safety, tolerability and PK of ulacamten when administered orally to healthy participants. The study design included seven single ascending dose cohorts (10 mg to 600 mg) comprised of 10 participants each, and two multiple-dose cohorts (100 and 200 mg once daily) comprised of 10 participants each. This study data demonstrated that ulacamten was safe and well tolerated in healthy participants. No serious adverse events were observed and the stopping criteria for the study were not met. The half-life of ulacamten was observed to be in the range of 14 to 17 hours. Ulacamten demonstrated dose-linearity without a change in half-life over a wide range of exposures, with a steady-state appearing evident within seven days of dosing. Left ventricular ejection fraction and left ventricular fractional shortening decreased from baseline in an exposure-dependent manner, and the pharmacokinetic/pharmacodynamic relationship appeared shallow and predictable. At the highest single dose of 600 mg, the mean decrease in LVEF was <5%. These results demonstrate pharmacologic properties that may enable once-daily fixed-dose administration in the future.

AMBER-HFpEF

In the fourth quarter of 2024, we announced the design of AMBER-HFpEF (Assessment of Ulacamten in a Multi-Center, Blinded Evaluation of Safety and Tolerability Results in HFpEF), a Phase 2 randomized, placebo-controlled, double-blind, multi-center, dose-finding clinical trial in patients with symptomatic HFpEF with left ventricular ejection fraction ≥ 60%. The primary objective is to evaluate the safety and tolerability profile of ulacamten compared to placebo. The secondary objectives include assessing the effect of ulacamten on LVEF and NT-proBNP, its pharmacokinetics, and its pharmacokinetic/pharmacodynamic relationship. AMBER-HFpEF is currently enrolling patients, and we expect to complete enrollment in cohort 2 of the study by the end of 2026.

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Royalty Pharma Revenue Interest

In the second quarter of 2024, we entered into a Revenue Participation Right Purchase agreement, which we refer to as the RP Ulacamten RPA, with RPI ICAV, pursuant to which RPI ICAV purchased rights to certain revenue streams from worldwide net sales of drug products containing ulacamten by us, our affiliates or licensees. Under the RP Ulacamten RPA, in consideration of an up-front $50 million payment, RPI ICAV purchased a revenue interest entitling it to 1.0% of our annual worldwide net sales of drug products containing ulacamten. In addition, following the initiation of the first Phase 3 clinical trial (or the Phase 3 portion of the first Phase 2b/3 clinical trial) in heart failure with preserved ejection fraction in humans for ulacamten, RPI ICAV, at its sole discretion, has the right to purchase an additional revenue interest which if exercised would entitle it to an additional 3.5% of our annual worldwide net sales of drug products containing ulacamten in consideration of a payment equal to 50.0% of our future research and development costs of a Phase 3 trial of ulacamten up to a maximum of $150 million.

Neuromuscular Program

Our neuromuscular program is focused on the activation of the skeletal sarcomere, the basic unit of skeletal muscle contraction. The skeletal sarcomere is a highly ordered cytoskeletal structure composed of skeletal muscle myosin, actin, and a set of regulatory proteins, which include the troponins and tropomyosin. This program leverages our expertise developed in our ongoing discovery and development of cardiac sarcomere activator.

We believe that our skeletal sarcomere activators may lead to new therapeutic options for diseases and medical conditions associated with neuromuscular dysfunction and potentially also conditions associated with aging and muscle weakness and wasting. The clinical effects of muscle weakness and wasting, fatigue and loss of mobility can range from decreased quality of life to, in some instances, life-threatening complications. By directly improving skeletal muscle function, a small molecule activator of the skeletal sarcomere potentially could enhance functional performance and quality of life in patients suffering from diseases or medical conditions associated with skeletal muscle weakness or wasting.

In the fourth quarter of 2024, we announced that the first participants have been dosed in a Phase 1 randomized, double-blind, placebo-controlled, multi-part, single and multiple ascending dose clinical study of CK-089 in healthy human participants. CK-089 is a fast skeletal muscle troponin activator with potential therapeutic application to a specific type of muscular dystrophy and other conditions of impaired muscle function. The primary objective of this Phase 1 randomized, double-blind, placebo-controlled, multi-part single and multiple ascending dose clinical study is to evaluate the safety, tolerability and pharmacokinetics of CK-089 when administered orally as single or multiple doses to healthy participants. The study design includes single ascending dose cohorts and multiple-dose ascending cohorts comprised of 10 participants each. Our clinical development program for CK-089 was subject to a partial clinical hold from FDA that limited our ability to dose patients at doses anticipated to result in plasma exposures higher than certain levels. FDA subsequently lifted the partial clinical trial hold, permitting us to continue our development program as intended.

Beyond Muscle Contractility

We developed preclinical expertise in the mechanics of skeletal, cardiac and smooth muscle that extends from proteins to tissues to intact animal models. Our translational research in muscle contractility has enabled us to better understand the potential impact of small molecule compounds that increase cardiac or skeletal muscle contractility and to apply those findings to the further evaluation of our drug candidates in clinical populations. In addition to contractility, other major functions of muscle play a role in certain diseases that could benefit from novel mechanism treatments. Accordingly, our knowledge of muscle contractility may serve as an entry point to the discovery of novel treatments for disorders involving muscle functions other than muscle contractility. We are leveraging our current understandings of muscle biology to investigate new ways of modulating these other aspects of muscle function for other potential therapeutic applications.

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Liquidity and Capital Resources

Our cash, cash equivalents, and investments and a summary of our borrowings and working capital as of March 31, 2026 and December 31, 2025 are summarized as follows (in thousands):

|  | March 31, 2026 |  |  | December 31, 2025 |
Financial assets: |  |  |  |  |  |
Cash and cash equivalents |  | $ | 129,843 |  |  | $ | 122,518 |
Short-term investments |  |  | 688,707 |  |  |  | 759,703 |
Long-term investments |  |  | 254,719 |  |  |  | 335,048 |
Total cash, cash equivalents, and marketable securities |  | $ | 1,073,269 |  |  | $ | 1,217,269 |
Borrowings: |  |  |  |  |  |
Term loans (including related derivative liabilities measured at fair value) |  | $ | 300,569 |  |  | $ | 297,644 |
Convertible notes, net |  |  | 891,559 |  |  |  | 890,618 |
Liabilities related to RPI transactions measured at fair value |  |  | 138,800 |  |  |  | 137,200 |
Total borrowings |  | $ | 1,330,928 |  |  | $ | 1,325,462 |
Working capital: |  |  |  |  |  |
Current assets |  | $ | 839,465 |  |  | $ | 916,975 |
Current liabilities |  |  | 199,185 |  |  |  | 202,452 |
Working capital |  | $ | 640,280 |  |  | $ | 714,523 |

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

|  | Three Months Ended |
|  | March 31, 2026 |  |  | March 31, 2025 |
Net cash used in operating activities |  | $ | (145,457 | ) |  | $ | (131,617 | )
Net cash provided by investing activities |  |  | 145,492 |  |  |  | 105,956 |
Net cash provided by financing activities |  |  | 7,770 |  |  |  | 4,754 |
Total |  | $ | 7,805 |  |  | $ | (20,907 | )

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 $145.5 million and $131.6 million in the three months ended March 31, 2026 and 2025, 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. In future quarters fluctuations in accounts receivable and inventories will impact cash flows used in operating activities. Net loss for the three months ended March 31, 2026 and 2025 included, among other items: stock-based compensation, interest expense on liabilities related to revenue participation right purchase agreements and debt, and/or changes in fair values related to derivative liabilities and liabilities related to RPI Transactions.

Cash Flows Provided by Investing Activities

Net cash provided by investing activities of $145.5 million in the three months ended March 31, 2026 was primarily due to maturities of investments offset by purchases of investments and property, plant and equipment.

Net cash provided by investing activities of $106.0 million in the three months ended March 31, 2025 was primarily due to maturities of investments offset by purchases of investments and property, plant and equipment.

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Cash Flows Provided by Financing Activities

Net cash provided by financing activities of $7.8 million in the three months ended March 31, 2026 was mainly due to net proceeds from stock-based award activities, offset by repayment of RP Multi Tranche Term Loan.

Net cash provided by financing activities of $4.8 million in the three months ended March 31, 2025 was mainly due to net proceeds from stock-based award activities, offset by repayment of RP Multi Tranche Term Loan.

2024 Royalty Pharma Transactions

In May 2024, we entered into a series of financing agreements with affiliates of Royalty Pharma, including the RP OM Loan Agreement, the RP Ulacamten RPA, the 2022 RP Multi Tranche Loan Agreement Amendment, the RP Aficamten RPA Amendment, and the RP Stock Purchase Agreement for a private placement of common stock concurrent with our underwritten public offering of common stock.

The RP OM Loan Agreement provides for a loan in the principal amount of $100.0 million that was drawn at the closing with no remaining amounts available for disbursement. The loan under the RP OM Loan Agreement matures on the 10 year anniversary of the funding date and is repayable in quarterly installments, the amounts of which will depend on the occurrence of certain events related to the results and timing of COMET-HF and potential regulatory approvals of omecamtiv mecarbil, as follows:

•
Scenario 1: If the Phase 3 clinical trial of Cytokinetics’ proprietary small molecule cardiac myosin activator known as omecamtiv mecarbil is successful (defined as meeting the composite primary endpoint of the first event, whichever occurs first, comprising of cardiovascular death, heart failure event, LVAD implementation/cardiac transplantation, or stroke, with a hazard ratio (HR) of less than 0.85 and cardiovascular death endpoint HR of less than 1.0) by June 30, 2028 and we receive the marketing approval from the FDA for omecamtiv mecarbil on or prior to December 31, 2029 (“OM Approval Date”), commencing on the calendar quarter during which the FDA approval is obtained, we are required to pay RPDF (x) (i) $75.0 million ten business days after the OM Approval Date and (ii) $25.0 million on the first anniversary of the OM Approval Date and (y) on a quarterly basis an amount equal to 2.0% of the annual worldwide net sales of omecamtiv mecarbil, subject to a minimum floor amount ranging from $5.0 million to $8.0 million during the first 18 calendar quarters (the payment of the 2.0% of the annual worldwide net sales starting from the 19th calendar quarter shall be referred to as the “Royalty Payment”). Our obligation to pay the Royalty Payment will continue after maturity of the Loan;
•
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 March 31, 2026. The remaining $175 million tranche 7 loan is also available to us now that the conditions for reimbursement, namely approval of our NDA for aficamten in patients with oHCM on or prior to December 31, 2025, have been met. We expect to draw Tranche 7 unless we are able to meet our financing requirements through more favorable funding sources.

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Each term loan under the RP Multi Tranche Loan Agreement matures on the 10 year anniversary of the funding date for such term loan and is repayable in quarterly installments of principal, interest and fees commencing on the last business day of the seventh full calendar quarter following the calendar quarter of the applicable funding date for such term loan, with the aggregate amount payable in respect of each term loan (including interest and other applicable fees) equal to 190% of the principal amount of the tranche 1, tranche 4, tranche 5, tranche 6, and tranche 7 term loans (such amount with respect to each term loan, “Final Payment Amount”). We commenced repayment of the RP Multi Tranche Loans in the fourth quarter of 2023 and will pay approximately $20.2 million in interest and principal on the term loans in 2026.

RP Aficamten Royalty Purchase Agreement

Under the RP Aficamten RPA, RPI ICAV purchased rights to certain revenue streams from net sales of pharmaceutical products containing aficamten by us, our affiliates and our licensees in exchange for up to $150.0 million in consideration, $50.0 million of which was paid on the closing date, $50.0 million of which was paid to us in March 2022 following the initiation of the first pivotal trial in oHCM for aficamten, and $50.0 million of which was paid to us in September 2023 following the initiation of the first pivotal clinical trial in nHCM for aficamten.

RPI ICAV initially purchased the right to receive a percentage of net sales equal to 4.5% for annual worldwide net sales of pharmaceutical products containing aficamten up to $1 billion and 3.5% for annual worldwide net sales of pharmaceutical products containing aficamten in excess of $1 billion, subject to reduction in certain circumstances. However, in May 2024, we entered into the RP Aficamten RPA Amendment to restructure the royalty so that RPI will now receive 4.5% up to $5.0 billion of worldwide annual net sales of aficamten and 1% above $5.0 billion of worldwide annual net sales. Our liability to RPI ICAV is referred to as the “RP Aficamten Liability”.

We account for the RP Aficamten Liability as a liability primarily because we have significant continuing involvement in generating the related revenue stream from which the liability will be repaid. When aficamten is commercialized and royalties become due, we will recognize the portion of royalties paid to RPI ICAV as a decrease to the RP Aficamten Liability and a corresponding reduction in cash.

The carrying amount of the RP Aficamten Liability is based on our estimate of the future royalties to be paid to RPI ICAV over the life of the arrangement as discounted using an imputed rate of interest. The imputed rate of interest on the carrying value of the RP Aficamten Liability was approximately 26.0% as of March 31, 2026 and 23.5% as of March 31, 2025.

Convertible Notes

On November 13, 2019, we issued $138.0 million aggregate principal amount of 2026 Notes. On July 6, 2022, we issued $540.0 million aggregate principal amount of 2027 Notes and used approximately $140.3 million of the net proceeds from the offering of 2027 Notes and issued 8,071,343 shares of common stock to repurchase approximately $116.9 million aggregate principal amount of the 2026 Notes pursuant to privately negotiated exchange agreements entered into with certain holders of the 2026 Notes concurrently with the pricing of the offering of the 2027 Notes. As a result of the partial repurchase of the 2026 Notes, we recorded a debt conversion expense of $22.2 million, consisting of the difference between the consideration to the holders pursuant to the exchange agreements and the if-converted value of the 2026 Notes under the original terms.

On September 19, 2025, we issued $750.0 million aggregate principal amount of 2031 Notes and used approximately $402.5 million of the net proceeds from the offering of 2031 Notes and issued 2,168,806 shares of common stock to repurchase approximately $399.5 million aggregate principal amount of the 2027 Notes pursuant to privately negotiated exchange agreements entered into with certain holders of the 2027 Notes concurrently with the pricing of the offering of the 2031 Notes. This resulted in recording debt conversion expense in the third quarter of 2025 of $121.2 million, consisting of the difference between the consideration to the holders pursuant to the exchange agreements and the if-converted value of the 2027 Notes under the original terms.

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As of March 31, 2026, 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 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.

Japan Out-license for Aficamten

In November 2024, we entered into a license and collaboration agreement with Bayer Consumer Care AG, an affiliate of Bayer AG, pursuant to which we granted to Bayer an exclusive license to develop and commercialize aficamten in Japan, subject to certain reserved development rights. Under the terms of the Bayer License Agreement, we received an up-front payment of €50.0 million (equivalent to $52.4 million at the time of payment) which was recorded as deferred revenue at December 31, 2024 and was recognized in 2025 upon completion of certain performance technology transfer obligations. We recognized revenue associated with two clinical milestones totaling €10 million in 2025. We recognized an additional €10 million milestone in the first quarter of 2026 as a result of our first commercial sale of MYQORZO in the United States. We may also be eligible to receive up to an additional €70 million in milestones upon first commercial sale of aficamten in each of oHCM and nHCM in Japan and nHCM in the United States. We are also eligible for an additional €490 million in commercial milestone payments upon the achievement by Bayer of certain sales milestones and tiered royalties on the net sales of pharmaceutical products containing aficamten in Japan ranging from the high teens to the low thirty percents, subject to certain reductions for generic competition, expiration of certain patents and payments for licenses to third-party patents, until the latest of the expiration of certain patents, the expiration of regulatory exclusivity for the Product in Japan, and the end of a minimum specified term.

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At-the-Market Sales of Common Stock

On February 27, 2025, we entered into an Open Market Sale Agreement SM 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 March 31, 2026, we have not sold any shares of Common Stock under the Open Market Sale Agreement SM with Jefferies LLC.

Future Uses of Cash

We expect that selling, general and administrative expenses will significantly increase in 2026. In December 2025, MYQORZO was approved by the FDA, and accordingly, our sales and marketing expenses will increase significantly as we engage in commercialization activities in the United States. In February 2026, the European Commission approved MYQORZO® (aficamten), 5 mg, 10 mg, 15 mg and 20 mg tablets for the treatment of symptomatic (NYHA class II-III) obstructive hypertrophic cardiomyopathy in adult patients, which means that we will significantly increase commercial readiness activities in Europe, initially in Germany, with commercial readiness activities in other major European countries to follow.

In future periods, we also expect to incur substantial costs as we expand our research programs and continue development activities, including for the conduct of our on-going clinical trials for aficamten, omecamtiv mecarbil, ulacamten and CK-089. We expect to incur significant research and development expenses as we advance the research and development of compounds from our other muscle biology programs through research to candidate selection to clinical development, and we expect to file investigational new drug applications. Cytokinetics and multiple third-party contract development manufacturing organizations entered into various scopes of work with respect to the manufacturing of aficamten. We have approximately $17.2 million of non-cancellable commitments related to purchases of materials and inventory manufacturing agreements.

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

•
the initiation, progress, timing, scope and completion of preclinical research, non-clinical development, CMC, and clinical trials for our drug candidates and other compounds;
•
the time, costs and outcomes of regulatory reviews or other regulatory actions related to our drugs and drug candidates,
•
the jurisdictions in which we are granted regulatory approvals and thus are able to successfully launch our products for commercial sale;
•
delays that may be caused by requirements of regulatory agencies;
•
our level of funding for the development of current or future drugs and drug candidates;
•
the number of drug candidates we pursue and the stage of development that they are in;
•
the costs involved in filing and prosecuting patent applications and attacking, enforcing or defending patent claims;
•
our ability to establish and maintain selected strategic alliances required for the development of drug candidates and commercialization of our drugs and future drugs, if any;
•
our plans or ability to expand our drug development capabilities, including our capabilities to conduct clinical trials for our drug candidates;
•
our plans or ability to engage third-party manufacturers for our drugs or drug candidates;
•
our plans or ability to build or access sales and marketing capabilities, including commercial infrastructure and distribution capabilities, and to achieve market acceptance for MYQORZO and potential future drugs;
•
the expansion and advancement of our research programs;
•
the hiring of additional employees and consultants;
•
the acquisition of technologies, products and other business opportunities that require financial commitments;
•
our revenues from commercialization of MYQORZO and successful development and commercialization of any other drug candidates;
•
the cost of additional construction to expand our headquarters in South San Francisco and the cost in relation to expanding our leased office facilities in Radnor, Pennsylvania or other leased office spaces in Europe; and
•
the payments due for interest on the term loan and convertible debt;

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We have incurred an accumulated deficit of approximately $3.7 billion since inception and there can be no assurance that we will attain profitability. Although we have one approved product at this time, we remain subject to risks common to clinical-stage companies including, but not limited to, development of new drug candidates, dependence on key personnel, and the ability to obtain additional capital as needed to fund our future plans. Our liquidity will be impaired if sufficient additional capital is not available on terms acceptable to us, if at all. Until we achieve profitable operations, we intend to continue to fund operations through payments from strategic collaborations, additional sales of equity securities, grants and other financings. With the recent FDA approval of MYQORZO in December 2025, we have only recently started generating revenues from the commercial sale of our drugs. Therefore, our success is dependent on our ability to generate substantial revenues from MYQORZO or potentially obtain additional capital by entering into new strategic collaborations and/or through financings, and ultimately on our and our collaborators’ ability to successfully develop and market one or more of our drug candidates. We cannot be certain that sufficient funds will be available from such collaborators or financings when needed or on satisfactory terms, including as a result of economic conditions, general global economic uncertainty, political change, war, the effects of inflationary pressures, including those resulting from tariffs and escalating trade tensions, and other factors including past and potential future bank failures in the United States. Additionally, there can be no assurance that MYQORZO or any of our drug candidates will be accepted in the marketplace or that any future products can be developed or manufactured at an acceptable cost. These factors could have a material adverse effect on our future financial results, financial position and cash flows.

Based on the current planning assumptions, we believe that our existing cash and cash equivalents, investments and interest earned on investments will be sufficient to meet our projected operating requirements for at least the next 12 months. If, at any time, our prospects for internally financing programs and activities decline, we may decide to reduce expenses across the business. Alternatively, we may raise funds through strategic relationships, public or private financings or other arrangements. There can be no assurance that funding, if needed, will be available on attractive terms, or at all, or in accordance with our planned timelines. Furthermore, financing obtained through future strategic relationships may require us to forego certain commercialization and other rights to our drug candidates. Similarly, any additional equity financing may be dilutive to stockholders and debt financing, if available, may involve restrictive covenants. Our failure to raise capital as and when needed could have a negative impact on our financial condition and our ability to pursue our business strategy.

Segment Information

We have one primary business activity and operate in one reportable segment.

Results of Operations

Revenues

Our revenues since inception were primarily from our collaboration partners. We did not generate any revenue from commercial product sales prior to the year ended December 31, 2025. MYQORZO for adults with symptomatic oHCM was approved by the FDA in December 2025 and our first commercial sale of MYQORZO occurred in the first quarter of 2026.

Revenues for the three months ended March 31, 2026 and 2025, were as follows (in thousands):

|  | Three Months Ended |  |  |  |
|  | March 31, 2026 |  |  | March 31, 2025 |  |  | Increase |
Net product revenue |  | $ | 4,789 |  |  | $ | — |  |  | $ | 4,789 |
Collaboration revenues |  |  | 2,637 |  |  |  | 1,579 |  |  |  | 1,058 |
License and milestone revenues |  |  | 11,929 |  |  |  | — |  |  |  | 11,929 |
Total revenues |  | $ | 19,355 |  |  | $ | 1,579 |  |  | $ | 17,776 |

Net product revenue was recorded for our first quarter of commercial sales of MYQORZO commencing in the last week of January 2026, for the quarter ended March 31, 2026.

Collaboration revenues for the three months ended March 31, 2026 were primarily from Bayer under the Bayer License Agreement related to certain research and development cost reimbursements. Collaboration revenues for the three months ended March 31, 2025 were from Sanofi under our collaboration and license agreement with Genzyme Corporation, an affiliate of Sanofi, and from Bayer related to certain research and development cost reimbursements.

License and milestone revenues for the three months ended March 31, 2026 were from Bayer related to the first commercial sale of MYQORZO in the United States.

As of March 31, 2026, the accounts receivable, net balance was $6.8 million comprised of $2.1 million related to Bayer and $0.2 million related to Sanofi and the remaining $4.5 million is associated with product revenue.

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Operating expenses

|  | Three Months Ended |  |  |  |
|  | March 31, 2026 |  |  | March 31, 2025 |  |  | Increase (decrease) |
Research and development |  | $ | 95,525 |  |  | $ | 98,262 |  |  | $ | (2,737 | )
Selling, general and administrative |  |  | 104,896 |  |  |  | 57,369 |  |  |  | 47,527 |
Cost of goods sold |  |  | 160 |  |  |  | — |  |  |  | 160 |
Collaboration cost of revenues (a) |  |  | 2,392 |  |  |  | 1,579 |  |  |  | 813 |
Total operating expenses |  | $ | 202,973 |  |  | $ | 157,210 |  |  | $ | 45,763 |

(a) Includes costs incurred in connection with manufacturing drug supplies for collaboration partners.

Operating expenses included stock-based compensation expense of $30.4 million and $23.5 million for the three months ended March 31, 2026 and 2025, respectively.

Research and development expenses

We incur research and development expenses that consist of employee compensation, supplies and materials, costs for consultants, contract research, clinical manufacturing and facilities and depreciation costs.

Research and development expenses for the three months ended March 31, 2026 and 2025, were as follows (in thousands):

|  | Three Months Ended |  |  |  |
|  | March 31, 2026 |  |  | March 31, 2025 |  |  | Decrease |
External costs: |  |  |  |  |  |  |  |  |
Aficamten |  | $ | 21,107 |  |  | $ | 29,548 |  |  | $ | (8,441 | )
Omecamtiv Mecarbil |  |  | 5,553 |  |  |  | 3,597 |  |  |  | 1,956 |
Other programs |  |  | 3,153 |  |  |  | 3,373 |  |  |  | (220 | )
Unallocated |  |  | 6,726 |  |  |  | 8,340 |  |  |  | (1,614 | )
Total external costs |  |  | 36,539 |  |  |  | 44,858 |  |  |  | (8,319 | )
Internal costs: |  |  |  |  |  |  |  |  |
Employee related |  |  | 45,532 |  |  |  | 40,027 |  |  |  | 5,505 |
Facilities, lab supplies and other |  |  | 13,454 |  |  |  | 14,956 |  |  |  | (1,502 | )
Total internal costs |  |  | 58,986 |  |  |  | 54,983 |  |  |  | 4,003 |
Total research and development expenses |  | $ | 95,525 |  |  | $ | 99,841 |  |  | $ | (4,316 | )

Research and development expenses for the three months ended March 31, 2026 decreased by $4.3 million compared to the three months ended March 31, 2025. The decrease was primarily due to higher clinical trial activity in 2025 partially offset by higher personnel-related costs in 2026.

Our development program for aficamten continues with CEDAR-HCM, our placebo-controlled and open-label extension clinical trial to evaluate the efficacy, pharmacokinetics (PK) and safety of aficamten in a pediatric population with symptomatic oHCM. Additionally, we have FOREST-HCM which is an open label extension study designed to assess the long-term safety and tolerability of aficamten in patients with HCM.

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.

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In the fourth quarter of 2024, we announced that the first participants have been dosed in a Phase 1 randomized, double-blind, placebo-controlled, multi-part, single and multiple ascending dose clinical study of CK-089 in healthy human participants. CK-089 is a fast skeletal muscle troponin activator with potential therapeutic application to a specific type of muscular dystrophy and other conditions of impaired muscle function. The primary objective of this Phase 1 randomized, double-blind, placebo-controlled, multi-part single and multiple ascending dose clinical study is to evaluate the safety, tolerability and pharmacokinetics of CK-089 when administered orally as single or multiple doses to healthy participants. The study design includes single ascending dose cohorts and multiple-dose ascending cohorts comprised of 10 participants each. Our clinical development program for CK-089 was subject to a partial clinical hold from FDA. FDA subsequently lifted the partial clinical trial hold, permitting us to continue our development program as intended.

We expect that research and development expenses will be flat to declining in 2026 relative to 2025 due to the completion of MAPLE-HCM and ACACIA-HCM, partially offset by the continuation of COMET-HF, AMBER HFpEF, CEDAR-HCM, FOREST-HCM and any additional clinical trials we may choose to undertake in connection with CK-089 or any other drug candidates.

Selling, general and administrative expenses

Selling, general and administrative expenses consist primarily of personnel costs, facilities and overhead costs, and selling, marketing and advertising expenses, as well as other general and administrative costs related to finance, human resources, legal and other administrative activities.

Selling, general and administrative expenses for the three months ended March 31, 2026 and 2025, were as follows (in thousands):

|  | Three Months Ended |  |  |  |
|  | March 31, 2026 |  |  | March 31, 2025 |  |  | Increase |
Total selling, general and administrative expenses |  | $ | 104,896 |  |  | $ | 57,369 |  |  | $ | 47,527 |

Selling, general and administrative expenses for the three months ended March 31, 2026 increased by $47.5 million from the three months ended March 31, 2025, primarily due to external costs associated with the commercial launch of MYQORZO and higher personnel related costs, including stock-based compensation.

We expect selling, general and administrative expenses to increase significantly in 2026. With the approval of MYQORZO in the United States, we expect to incur additional expenses for commercial activities, including, but not limited to, the full year impact of the U.S. sales force, training and education, the implementation of compliance systems, patient support programs, sales and marketing expenses. In addition, the European Commission approved MYQORZO for the treatment of adults with symptomatic oHCM, (NYHA class II-III), and therefore, we expect to incur similar expenses for commercial readiness activities in Europe but with additional expenses for the establishment of a corporate infrastructure to enable commercialization activities in key European markets, beginning in Germany with other major European markets to follow.

Cost of Goods Sold

Costs of goods sold for the three months ended March 31, 2026 and 2025, were as follows (in thousands):

|  | Three Months Ended |  |  |  |
|  | March 31, 2026 |  |  | March 31, 2025 |  |  | Increase |
Total cost of goods sold |  | $ | 160 |  |  | $ | — |  |  | $ | 160 |

We received FDA approval for MYQORZO on December 19, 2025 and began capitalizing inventories upon FDA approval. Costs incurred prior to approval were recorded as research and development expense in our condensed consolidated statement of operations and comprehensive loss. As a result, cost of sales for the next several quarters are expected to reflect a lower average per unit cost of materials, it was immaterial for the quarter ended March 31, 2026.

Collaboration Cost of Revenues

Collaboration cost of revenues includes cost reimbursements as well as costs incurred in connection with manufacturing drug supplies for collaboration partners. Collaboration of costs of sales for the three months ended March 31, 2026 and 2025, were as follows (in thousands):

|  | Three Months Ended |  |  |  |
|  | March 31, 2026 |  |  | March 31, 2025 |  |  | Increase |
Total collaboration cost of revenues |  | $ | 2,392 |  |  | $ | 1,579 |  |  | $ | 813 |

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Collaboration cost of revenues for the three months ended March 31, 2026 were primarily from Bayer under the Bayer License Agreement related to certain research and development cost reimbursements. Collaboration revenues for the three months ended March 31, 2025 were from Sanofi under our collaboration and license agreement with Genzyme Corporation, an affiliate of Sanofi, and from Bayer related to certain research and development cost reimbursements.

Interest Expense

Interest expense for the three months ended March 31, 2026 and 2025, was as follows (in thousands):

|  | Three Months Ended |  |  |  |
|  | March 31, 2026 |  |  | March 31, 2025 |  |  | Increase |
Term loans |  | $ | 8,745 |  |  | $ | 3,118 |  |  | $ | 5,627 |
2026 Notes |  |  | 238 |  |  |  | 237 |  |  |  | 1 |
2027 Notes |  |  | 1,434 |  |  |  | 5,472 |  |  |  | (4,038 | )
2031 Notes |  |  | 4,027 |  |  |  | — |  |  |  | 4,027 |
Other |  |  | 75 |  |  |  | 41 |  |  |  | 34 |
Total interest expense |  | $ | 14,519 |  |  | $ | 8,868 |  |  | $ | 5,651 |

Term loan interest is related to the RP Multi Tranche Loan and it increased year over year due to four tranches of interest expense being incurred in first quarter of 2026 due to Tranches 1, 4, 5 and 6 compared to two tranches in the first quarter of 2025 related to Tranche 1 and 6. In September 2025, we issued the 2031 Notes and used the net proceeds and common stock to partially repurchase the 2027 Notes. Due to the balance of the 2027 Notes declining in the third quarter of 2025, interest expense declined year over year.

Interest expense in 2026 is expected to increase further because of the $100 million drawn in October 2025 for Tranche 5 which will be outstanding for the entirety of 2026. Interest expense may increase further if we draw on Tranche 7.

Non-cash interest expense on liabilities related to revenue participation right purchase agreements

Non-cash interest expense results from the accretion of our liabilities to RPFT and RP ICAV related to the sale of future royalties under the RP OM RPA and the RP Aficamten RPA, respectively.

Non-cash interest expense on liability related to the RP OM RPA and the RP Aficamten RPA for the three months ended March 31, 2026 and 2025 were as follows (in thousands):

|  | Three Months Ended |  |  |  |
|  | March 31, 2026 |  |  | March 31, 2025 |  |  | Increase |
RP OM Liability |  | $ | — |  |  | $ | 41 |  |  | $ | (41 | )
RP Aficamten Liability |  |  | 18,816 |  |  |  | 14,037 |  |  |  | 4,779 |
Total non-cash interest expense recognized |  | $ | 18,816 |  |  | $ | 14,078 |  |  | $ | 4,738 |

The carrying amount of the RP Aficamten Liability is based on our estimate of the future royalties to be paid pursuant to RP Aficamten RPA over the life of the arrangement as discounted using an imputed rate of interest. The imputed rate of interest on the carrying value of the RP Aficamten Liability was approximately 26.0% as of March 31, 2026 and 23.5% as of March 31, 2025.

The carrying amount of the RP OM Liability is based on our estimate of the future royalties to be paid pursuant to RP OM RPA over the life of the arrangement as discounted using an imputed rate of interest. The excess of future estimated royalty payments over the $92.3 million of allocated proceeds, less issuance costs, is recognized as non-cash interest expense using the effective interest method. The imputed rate of interest on the carrying value of the RP OM Liability is reassessed periodically and is not reduced below 0%. The imputed rate of interest on the carrying value of the RP OM Liability was 0.0% as of March 31, 2026 and approximately 0.1% as of March 31, 2025.

We review our assumptions on a regular basis and our estimates may change in the future as we refine and reassess our assumptions.

Interest and Other Income, net

Interest and other income, net for the three months ended March 31, 2026 and 2025 consisted primarily of interest income generated from our cash, cash equivalents and investments.

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Change in fair value liabilities related to RPI transactions and derivative liabilities reflected on the Condensed Consolidated Statement of Operations.

The change in fair value liabilities related to the RPI transactions (RP OM Loan Agreement and RP Ulacamten RPA) and the derivative liabilities for the RP Multi Tranche Loan Agreement for the three months ended March 31, 2026 and 2025 were as follows (in thousands):

|  | Three Months Ended |  |  |  |
|  | March 31, 2026 |  |  | March 31, 2025 |  |  | Decrease |
RP Ulacamten RPA |  | $ | 200 |  |  | $ | 300 |  |  | $ | (100 | )
RP OM Loan |  |  | (1,800 | ) |  |  | 3,600 |  |  |  | (5,400 | )
RP Multi Tranche Loan Agreement Derivatives |  |  | 1,500 |  |  |  | (400 | ) |  |  | 1,900 |
Total change in fair value liabilities |  | $ | (100 | ) |  | $ | 3,500 |  |  | $ | (3,600 | )

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 12% to 17% as of March 31, 2026 and 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 12% to 13% for the three months ended March 31, 2026 and 12% to 14% for the three months ended March 31, 2025) and other factors.

The total change in the estimated fair value liabilities for the three months ended March 31, 2026 was primarily driven by changes in the discount rates used in the valuation of the 2024 RP OM Loan and the derivatives associated with the RP Multi Tranche Loan Agreement.

Critical Accounting Policies and Significant Estimates

The accounting policies that we consider to be our most critical (i.e., those that are most important to the portrayal of our financial condition and results of operations and that require our most difficult, subjective or complex judgments), the effects of those accounting policies applied and the judgments made in their application are summarized in “Item 7 — Management’s Discussion and Analysis of Financial Condition and Results of Operations — Critical Accounting Policies and Significant Estimates” in our Annual Report on Form 10-K for the fiscal year ended December 31, 2025. There have been no material changes to our critical accounting policies and significant estimates in the three months ended March 31, 2026 , except for the following:

Net Product Revenue

We recognize revenue from product sales at a point in time when our customer is deemed to have obtained control of the product, which generally occurs upon receipt or acceptance by our customer. In order to determine the transaction price, we estimate, utilizing the expected value method, the amount of variable consideration to which we will be entitled. Our product sales are subject to various deductions, including distribution-related fees, rebates under government programs, rebates for commercial payors, and amounts under our co-pay assistance program. The distribution-related fees include a prompt pay discount and fees for specialty pharmaceutical and specialty distributor customers. The distribution-related fees are not subject to significant estimation uncertainty. However, other sales deductions require us to make estimates, particularly related to the payor mix. We estimate the percentage of product sales which will ultimately be subject to commercial payor rebates, the Medicare Part D Manufacturer Rebate Program, Medicaid, and other federal programs. We also estimate the percentage of product sales which will ultimately go to 340B hospitals. As we have limited history for the sales of MYQORZO, we estimated our payor mix based upon our market research and industry data for similar cardiovascular products. As we gain more historical experience for the sales of MYQORZO, we will update our estimates which will result in adjustments to current period revenues.

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Inventories

Inventories, which consist of raw materials, work in process and finished goods, are stated at the lower of cost or estimated net realizable value, using standard costs, based on a first-in, first-out method. We have entered into manufacturing and supply agreements for the manufacture or purchase of raw materials and production supplies in prior years. Our inventories include the direct purchase cost of materials and supplies, charges from contract manufacturing organizations and manufacturing overhead costs. We will periodically review our inventories for factors that could impact the future recoverability and realization of future sales, which require estimates and judgments. We will analyze our inventory levels quarterly and write down inventories subject to expiry, in excess of expected requirements or that has a cost basis in excess of its expected net realizable value. These write downs will be charged to cost of sales in the accompanying consolidated statements of operations and comprehensive loss.

We received FDA approval for MYQORZO on December 19, 2025 and began capitalizing inventories upon FDA approval. Costs incurred prior to approval have been recorded as research and development expense in our consolidated statement of operations and comprehensive loss. As a result, inventory balances and cost of sales for the next several quarters are expected to reflect a lower average per unit cost of materials.

ITEM 3. QUANTITATIVE AND QUALITATI VE DISCLOSURES ABOUT MARKET RISK

Our exposure to market risk has not changed materially since our disclosures in "Item 7A —Quantitative and Qualitative Disclosures About Market Risk” in our Annual Report on Form 10-K for the year ended December 31, 2025, except for the following:

Interest Rate Risk

We are exposed to market risk related to changes in interest rates. As of March 31, 2026, our cash and investments totaled $1.1 billion, comprising U.S. Treasury securities, U.S. and non-U.S. government agency bonds, commercial paper, a global portfolio of corporate debt, money market funds, and repurchase agreements backed by U.S. Treasury securities.

Our investments are subject to interest rate risk and could fall in value if market interest rates increase. We have not been exposed to, nor do we anticipate being exposed to, material risks due to changes in interest rates. A hypothetical 1% increase in market interest rates would result in a decline in the value of our investments of approximately $5.1 million and $6.0 million as of March 31, 2026 and December 31, 2025, respectively.

In addition, we have elected the fair value option for certain liabilities. The fair value of the liabilities related to 2024 RP OM Loan Agreement, the RP Ulacamten RPA, and the derivatives of the RP Multi Tranche Loan Agreement will increase as market interest rates decrease. In addition, the fair value of the liabilities may fluctuate based upon changes in the Company’s credit rating. Changes in the interest rate environment and the credit rating of the Company could have an effect on our future earnings. For example, a hypothetical 1% decrease in the discount rates used to measure the 2024 RP OM Loan Agreement, the RP Ulacamten RPA, and the derivatives of the RP Multi Tranche Loan Agreement would result an increase in the fair value, and the recognition of a loss, of approximately $4.0 million as of March 31, 2026. During the three months ended March 31, 2026, we recognized a loss on the change in the estimated fair value of liabilities of approximately $1.6 million, primarily due to changes in the discount rates used to measure the 2024 RP OM Loan Agreement and the RP Ulacamten RPA. The discount rates ranged from 12% to 17% as of March 31, 2026 and 2025.

ITEM 4. CONTROLS AND PROCEDURES

(a) Evaluation of disclosure controls and procedures

We maintain disclosure controls and procedures that are designed to ensure that information required to be disclosed in our reports under the Exchange Act, and the rules and regulations thereunder, is recorded, processed, summarized and reported within the time periods specified in the SEC’s rules and forms and that such information is accumulated and communicated to our management, including our principal executive officer and principal financial officer, or persons performing similar functions, as appropriate, to allow for timely decisions regarding required or necessary disclosure. In designing and evaluating the disclosure controls and procedures, management recognizes that any controls and procedures, no matter how well designed and operated, can provide only reasonable, not absolute, assurance of achieving the desired control objectives, and we are required to apply judgment in evaluating the cost-benefit relationship of possible controls and procedures. Based on the evaluation of our disclosure controls and procedures as of March 31, 2026, our Chief Executive Officer and Chief Financial Officer concluded that, as of such date, our disclosure controls and procedures were effective at the reasonable assurance level.

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(b) Changes in internal control over financial reporting

Except for new controls implemented related to product revenues and inventory, there were no changes in our internal control over financial reporting that occurred during the quarter ended March 31, 2026, that have materially affected, or are reasonably likely to materially affect, our internal control over financial reporting.

(c) Limitations on the effectiveness of controls

A control system, no matter how well-conceived and operated, can provide only reasonable, not absolute, assurance that the objectives of the controls are met. Because of the inherent limitations in all control systems, no evaluation of controls can provide absolute assurance that all control issues, if any, within a company have been detected. Accordingly, our disclosure controls and procedures are designed to provide reasonable, not absolute, assurance that the objectives of our disclosure control system are met.

PART II. OTHER INFORMATION

ITEM 1. LEGAL PROCEEDINGS

In re Cytokinetics, Incorporated Securities Litigation

On September 17, 2025, a putative stockholder class action lawsuit was filed against the Company and its Chief Executive Officer in the United States District Court for the Northern District of California, alleging violations of 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 the Company's common stock between December 27, 2023 and May 6, 2025. The complaint alleges that the Company made materially false and misleading statements regarding the timeline for the NDA regulatory approval process for aficamten and failed to disclose related material risks. The complaint seeks unspecified damages, together with interest, attorneys' fees, and costs.

On December 22, 2025, the Court appointed Gilbert Rosenthal as Lead Plaintiff and approved his selection of Pomerantz LLP as Lead Counsel. The action is now captioned In re Cytokinetics, Incorporated Securities Litigation, Case No. 3:25-cv-07923-RFL. On March 10, 2026, Lead Plaintiff filed an amended complaint, which, among other things, added the Company's Chief Financial Officer as a defendant. The Company expects to file a motion to dismiss the amended complaint within 60 days of its filing.

The Company disputes the allegations in the amended complaint and intends to vigorously defend against the action.

Pohlmann v. Blum, et al.

On March 9, 2026, a purported stockholder derivative action captioned Pohlmann v. Blum, et al., Case No. 3:26-cv-01998-RFL, was filed in the United States District Court for the Northern District of California against certain of the Company's current and former directors and its Chief Executive Officer, with the Company named as a nominal defendant. The complaint asserts claims for breach of fiduciary duty, aiding and abetting breach of fiduciary duty, unjust enrichment, waste of corporate assets, contribution under the Securities Exchange Act of 1934, and violations of Section 14(a) of the Securities Exchange Act of 1934 and Rule 14a-9 promulgated thereunder. The allegations are based substantially on the same underlying facts and circumstances as those alleged in In re Cytokinetics, Incorporated Securities Litigation and principally concern statements regarding the Company's New Drug Application for aficamten and the subsequent extension of the related PDUFA action date. The complaint seeks, among other relief, unspecified damages on behalf of the Company, disgorgement, corporate governance reforms, and attorneys' fees and costs.

On March 27, 2026, the Court found the derivative action to be related to In re Cytokinetics, Incorporated Securities Litigation and reassigned the matter accordingly. On April 16, 2026, the Court entered an order, pursuant to the parties' stipulation, staying the derivative action in its entirety during the pendency of any motion to dismiss in the securities class action, subject to customary terms.

The Company and the individual defendants dispute the allegations in the derivative action and intend to vigorously defend against the matter.

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ITEM 1A. RI SK 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 Quarterly Report on Form 10-Q 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.

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.

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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.

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 to no 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.

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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.

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, and in April 2026, the United States administration issued a Proclamation regarding the imposition of such tariffs (the Pharmaceutical Tariffs). There remains substantial uncertainty as to the implementation and potential impact of such tariffs and, more generally, about the duration of existing tariffs and whether additional tariffs or other retaliatory measures may be imposed, modified or suspended. For example, the U.S. Supreme Court ruled in February 2026 that certain tariffs imposed by the U.S. federal government under the International Emergency Economic Powers Act exceeded presidential authority and therefore are invalid. However, tariffs imposed under different statutes (including the Pharmaceutical Tariffs) were not directly impacted by the decision and therefore remain in place. 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.

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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.

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 obtain 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 breast-fed 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.

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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.

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.

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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.

Although we have announced positive topline results from ACACIA-HCM, our Phase 3 clinical trial of aficamten in patients with nHCM, the regulatory pathway for approval of aficamten for the treatment of nHCM depends on the totality of clinical data and regulatory agencies’ interpretations of what constitutes a minimally important clinical difference in the trial's functional endpoints, which can be subjective because there is no universally established standard. FDA, EMA and/or other regulatory agencies may determine that the results from ACACIA-HCM 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.

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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.

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.

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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.

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.

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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 that an Issue Notification for US Patent No. 12,616,697 has been sent by the U.S. Patent and Trademark Office to the patent holder, Myokardia, Inc., a subsidiary of Bristol Myers Squibb. The patent, with expected issuance on May 5, 2026, claims the method of treating patients with HCM or HFpEF who are already undergoing beta blocker therapy, the method comprising discontinuation or reduction of beta blocker therapy and the administration of a therapeutically effective amount of a myosin inhibitor (including MYQORZO). Upon issuance, the patent holder may assert that its patent claims cover certain aspects of using MYQORZO for treating patients with HCM who are then currently on beta blocker therapy. 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.

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.

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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 March 31, 2026 and December 31, 2025 we had $1.3 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. Additionally we have liabilities related to revenue participation right purchase agreements of $539.1 million and $520.6 million at March 31, 2026 and December 31, 2025, 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.

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.

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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.

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.

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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/or 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.

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 ("MFN") 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 model, which is a specific part of the broader proposed MFN drug pricing initiatives to apply MFN pricing to Medicare Part D, announced by the agency in late 2025. If enacted, these initiatives 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.

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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.

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.

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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.

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.

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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.

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.

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ITEM 2. UNREGISTERED SALES OF EQUI TY SECURITIES AND USE OF PROCEEDS

None.

ITEM 3. DEFAULTS UPO N SENIOR SECURITIES

None.

ITEM 4. MINE SAFE TY DISCLOSURES

None.

ITEM 5. OTHER INFORMATION

(c) In this Item 5(c) of this quarterly report on Form 10-Q, the terms “officers”, “rule 10b5-1 trading arrangements” and “non-Rule 10b5-1 trading arrangements” have the meanings ascribed to them in Item 408 of Regulation S-K.

The following directors and officers adopted into or terminated a Rule 10b5-1 trading arrangement during the first quarter of 2026:

•
Edward M. Kaye, M.D. – Dr. Kaye, a member of our board of directors, adopted a Rule 10b5-1 trading arrangement on March 2, 2026 that was intended to satisfy the affirmative defense provided for under Rule 10b5-1(c) (the “Kaye Plan”). The Kaye Plan provides for the sale of up to 29,347 shares of our common stock, subject to certain conditions. The Kaye Plan will terminate on the earlier of (x) February 28, 2027 and (y) the sale of all securities that are subject to the plan.

Certain of our officers have made elections to participate in, and are participating in, our employee stock purchase plan, which may be designed to satisfy the affirmative defense conditions of Rule 10b5-1 under the Exchange Act or may constitute non-Rule 10b5–1 trading arrangements. In addition, certain of our directors have made elections to participate in, and are participating in, our director equity in lieu of cash retainer option program (as described in the “Director Compensation” section of our Proxy Statement for our 2024 Annual Meeting), which may be designed to satisfy the affirmative defense conditions of Rule 10b5-1 under the Exchange Act or may constitute non-Rule 10b5–1 trading arrangements.

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ITEM 6. EXHIBITS

|  |  |  | Incorporated by Reference |
Exhibit No. |  |  |  | Form |  | File No. |  | Filing Date |  | Exh. No. |  | Filed Herewith
3.1 |  | Amended and Restated Certificate of Incorporation |  | S-3 |  | 333-174869 |  | June 13, 2011 |  | 3.1 |  |
3.2 |  | Certificate of Amendment of Amended and Restated Certificate of Incorporation |  | 10-Q |  | 000-50633 |  | August 4, 2011 |  | 3.2 |  |
3.3 |  | Certificate of Amendment of Amended and Restated Certificate of Incorporation |  | 8-K |  | 000-50633 |  | June 25, 2013 |  | 5.1 |  |
3.4 |  | Certificate of Amendment of Amended and Restated Certificate of Incorporation |  | 8-K |  | 000-50633 |  | May 20, 2016 |  | 3.1 |  |
3.5 |  | Certificate of Amendment of Amended and Restated Certificate of Incorporation |  | 10-Q |  | 000-50633 |  | August 3, 2023 |  | 3.5 |  |
3.6 |  | Certificate of Amendment of Amended and Restated Certificate of Incorporation |  | 10-Q |  | 000-50633 |  | August 7, 2025 |  | 3.6 |  |
3.7 |  | Amended and Restated Bylaws |  | 8-K |  | 000-50633 |  | February 17, 2023 |  | 3.1 |  |
4.1 |  | Specimen Common Stock Certificate |  | 10-Q |  | 000-50633 |  | May 9, 2007 |  | 4.1 |  |
4.2 |  | Form of Warrant Issuable to Oxford Finance LLC pursuant to that certain Loan and Security Agreement, dated as of May 17, 2019, by and among the Company, Oxford Finance LLC and Silicon Valley Bank |  | 10-Q |  | 000-50633 |  | August 9, 2019 |  | 4.2 |  |
4.3 |  | Base Indenture, dated November 13, 2019, between the Company and U.S. Bank National Association, as Trustee |  | 8-K |  | 000-50633 |  | November 13, 2019 |  | 4.1 |  |
4.4 |  | First Supplemental Indenture, dated November 13, 2019, between the Company and U.S. Bank National Association, as Trustee (including the form of 4.00% Convertible Senior Notes due 2026) |  | 8-K |  | 000-50633 |  | November 13, 2019 |  | 4.2 |  |
4.5 |  | Indenture, dated July 6, 2022, between the Company and U.S. Bank Trust Company, National Association, as Trustee (including the form of 3.50% Convertible Senior Notes due 2027) |  | 8-K |  | 000-50633 |  | July 6, 2022 |  | 4.1 |  |
4.6 |  | Indenture, dated as of September 19, 2025, between the Company and U.S. Bank Trust Company, National Association, as Trustee (including the form of 1.75% Convertible Senior Notes due 2031) |  | 8-K |  | 000-50633 |  | September 22, 2025 |  | 4.1 |  |
4.6 |  | Certificate of Designation |  | 8-K |  | 000-50633 |  | April 18, 2011 |  | 4.5 |  |
4.7 |  | Certificate of Designation |  | 8-K |  | 000-50633 |  | June 30, 2012 |  | 4.1 |  |
4.8 |  | Certificate of Change of Registered Agent |  | 10-K |  | 000-50633 |  | March 1, 2023 |  | 4.9 |  |
31.1 |  | Certification of Principal Executive Officer pursuant to Rule 13a-14(a) and Rule 15d-14(a) of the Securities Exchange Act, as amended |  |  |  |  |  |  |  |  |  | X
31.2 |  | Certification of Principal Financial Officer pursuant to Rule 13a-14(a) and Rule 15d-14(a) of the Securities Exchange Act, as amended |  |  |  |  |  |  |  |  |  | X
32.1 |  | Certifications of the Principal Executive Officer and Principal Financial Officer pursuant to 18 U.S.C 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002(1) |  |  |  |  |  |  |  |  |  | X

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101.INS |  | Inline XBRL Instance Document (the Instance Document does not appear in the Interactive Data File because its XBRL tags are embedded within the Inline XBRL document) |  |  |  |  |  |  |  |  |  | X
101.SCH |  | Inline XBRL Taxonomy Extension Schema with Embedded Linkbase Document |  |  |  |  |  |  |  |  |  | X
104 |  | Cover Page Interactive Data File (formatted as Inline XBRL and contained in Exhibit 101) |  |  |  |  |  |  |  |  |  | X
(1) This certification accompanies the Form 10-Q to which it relates, is not deemed filed with the Securities and Exchange Commission and is not to be incorporated by reference into any filing of the Registrant under the Securities Act of 1933, as amended, or the Securities Exchange Act of 1934, as amended (whether made before or after the date of the Form 10-Q), irrespective of any general incorporation language contained in such filing.

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SIGNATURES

Pursuant to the requirements of the Securities Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

Dated: May 5, 2026 |  | CYTOKINETICS, INCORPORATED
|  | (Registrant)
|  | /s/ Robert I. Blum
|  | Robert I. Blum
|  | President and Chief Executive Officer
|  | (Principal Executive Officer)
|  | /s/ Sung H. Lee
|  | Sung H. Lee
|  | Executive Vice President, Chief Financial Officer
|  | (Principal Financial Officer)

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