CYTOKINETICS REPORTS THIRD QUARTER 2023 FINANCIAL RESULTS

On Track for Topline Results from SEQUOIA-HCM

a Pivotal Phase 3 Clinical Trial of Aficamten in Obstructive HCM,

in Late December

Long-Term Data from FOREST-HCM,

the Open-Label Extension Study of Aficamten,

Show Sustained Improvements in Clinical Efficacy Endpoints

and No Treatment Interruptions for Low Ejection Fraction

Initiated Enrollment in ACACIA-HCM,

a Pivotal Phase 3 Clinical Trial of Aficamten in Non-Obstructive HCM

SOUTH SAN FRANCISCO, Calif., Nov. 2, 2023 - Cytokinetics, Incorporated (Nasdaq: CYTK) reported financial results for the third quarter of 2023. Net loss for the third quarter was $129.4 million, or $1.35 per share, compared to net loss for the third quarter of 2022 of $142.3 million, or $1.52 per share. Cash, cash equivalents and investments totaled $554.7 million on September 30, 2023.

“During the third quarter we made considerable progress across our specialty cardiology franchise, with aficamten remaining our top priority. Of note, the baseline characteristics of patients enrolled in SEQUOIA-HCM met our objectives for the trial and align with our goal to assess aficamten as a potential next-in-class cardiac myosin inhibitor in a population with a substantial deficit in exercise capacity and significant symptom burden despite existing standard of care,” said Robert I. Blum, Cytokinetics’ President and Chief Executive Officer. “In addition, we recently shared longer-term data from FOREST-HCM that demonstrate durable reductions in pressure gradients and cardiac biomarkers as well as improved symptoms in patients with obstructive HCM. During the quarter we also started ACACIA-HCM, a pivotal Phase 3 clinical trial of aficamten in patients with non-obstructive HCM. Alongside these increasing commitments to aficamten, we are approaching the end of 2023 in a strong position with the resources and pipeline to execute on our goals in service to both patients and shareholders.”

Q3 and Recent Highlights

Cardiac Muscle Programs

aficamten (cardiac myosin inhibitor)

omecamtiv mecarbil (cardiac myosin activator)

CK-3828136 (CK-136, cardiac troponin activator)

CK-4021586 (CK-586, cardiac myosin inhibitor)

Pre-Clinical Development and Ongoing Research

Corporate

Upcoming Corporate Milestones

Cardiac Muscle Programs

aficamten (cardiac myosin inhibitor)

omecamtiv mecarbil (cardiac myosin activator)

CK-3828136 (CK-136, cardiac troponin activator)

CK-4021586 (CK-586, cardiac myosin inhibitor)

Financials

Revenues for the three and nine months ended September 30, 2023 were $0.4 million and $5.9 million (inclusive of $2.5 million milestone, in the nine months ended, from Ji Xing Pharmaceuticals upon the start of ACACIA-HCM), respectively, compared to $2.5 million and $92.6 million (inclusive of $87 million from the sale of our royalty on mavacamten) for the corresponding periods in 2022.

Research and development expenses for the three and nine months ended September 30, 2023 increased to $82.5 million and $245.2 million, respectively, compared to $62.7 million and $165.8 million for the same periods in 2022, respectively, due primarily to increased spending for our cardiac myosin inhibitor programs.

General and administrative expenses for the three months ended September 30, 2023 decreased to $40.1 million from $48.2 million from the three months ended September 20, 2022, primarily due to lower outside services spend. General and administrative expenses for the nine months ended September 30, 2023 increased to $129.5 million from $124.0 million from the nine months ended September 20, 2022, primarily due to higher personnel related cost including stock-based compensation offset by lower outside service spend.

During the quarter we also received a $50 million cash milestone payment from Royalty Pharma plc upon the start of ACACIA-HCM, treated as a liability on our balance sheet in accordance with GAAP.

Conference Call and Webcast Information

Members of Cytokinetics’ senior management team will review the company’s third quarter 2023 results on a conference call today at 4:30 PM Eastern Time. The conference call will be simultaneously webcast and can be accessed from the Investors & Media section of Cytokinetics’ website at www.cytokinetics.com. The live audio of the conference call can also be accessed by telephone by registering in advance at the following link: Cytokinetics Q3 2023 Earnings Conference Call. Upon registration, participants will receive a dial-in number and a unique passcode to access the call. An archived replay of the webcast will be available via Cytokinetics’ website for twelve months.

About Cytokinetics

Cytokinetics is a late-stage, specialty cardiovascular biopharmaceutical company focused on discovering, developing and commercializing first-in-class muscle activators and next-in-class muscle inhibitors as potential treatments for debilitating diseases in which cardiac muscle performance is compromised. As a leader in muscle biology and the mechanics of muscle performance, the company is developing small molecule drug candidates specifically engineered to impact myocardial muscle function and contractility. Aficamten is a next-in-class cardiac myosin inhibitor, currently the subject of three Phase 3 clinical trials: SEQUOIA-HCM, evaluating aficamten in patients with obstructive hypertrophic cardiomyopathy (HCM), MAPLE-HCM, evaluating aficamten as monotherapy compared to metoprolol as monotherapy in patients with obstructive HCM and ACACIA-HCM, evaluating aficamten in patients with non-obstructive HCM. Cytokinetics is also developing omecamtiv mecarbil, a cardiac muscle activator, in patients with heart failure. Additionally, Cytokinetics is developing CK-136, a cardiac troponin activator for the potential treatment HFrEF and other types of heart failure, such as right ventricular failure, resulting from impaired cardiac contractility, and CK-586, a cardiac myosin inhibitor with a mechanism of action distinct from aficamten for the potential treatment of HFpEF. In 2023, Cytokinetics is celebrating its 25-year history of pioneering innovation in muscle biology and related pharmacology focused to diseases of muscle dysfunction and conditions of muscle weakness.

For additional information about Cytokinetics, visit www.cytokinetics.com and follow us on X, LinkedIn, Facebook and YouTube.

Forward-Looking Statements

This press release contains forward-looking statements for purposes of the Private Securities Litigation Reform Act of 1995 (the “Act”). Cytokinetics claims the protection of the Act’s Safe Harbor for forward-looking statements. Examples of such statements include, but not limited to, statements, express or implied, relating to our or our partners’ research and development and commercial readiness activities, including the initiation, conduct, design, enrollment, progress, continuation, completion, timing and results of any of our clinical trials, or more specifically, our ability to obtain approval of our marketing authorisation application for omecamtiv mecarbil in the E.U., our ability to publish topline results of SEQUOIA-HCM by the end of 2023, the timing of interactions with FDA or any other regulatory authorities in connection to any of our drug candidates and the outcomes of such interactions; statements regarding the potential outcome of our Formal Dispute Resolution Request to FDA regarding the Complete Response Letter (CRL) for omecamtiv mecarbil, statements relating to the potential patient population who could benefit from omecamtiv mecarbil, aficamten, CK-136, CK-586 or any of our other drug candidates; statements relating to our ability to receive additional capital or other funding, including, but not limited to, our ability to meet any of the conditions relating to or to otherwise secure additional loan disbursements under any of our agreements with entities affiliated with Royalty Pharma or additional milestone payments from Ji Xing; statements relating to our operating expenses or cash utilization for the remainder of 2023, and statements relating to our cash balance at year-end 2023 or any other particular date or the amount of cash runway such cash balances represent at any particular time. Such statements are based on management's current expectations, but actual results may differ materially due to various risks and uncertainties, including, but not limited to Cytokinetics’ need for additional funding and such additional funding may not be available on acceptable terms, if at all; potential difficulties or delays in the development, testing, regulatory approvals for trial commencement, progression or product sale or manufacturing, or production of Cytokinetics’ drug candidates that could slow or prevent clinical development or product approval; patient enrollment for or conduct of clinical trials may be difficult or delayed; the FDA or foreign regulatory agencies may delay or limit Cytokinetics’ or its partners’ ability to conduct clinical trials; Cytokinetics may incur unanticipated research and development and other costs; standards of care may change, rendering Cytokinetics’ drug candidates obsolete; and competitive products or alternative therapies may be developed by others for the treatment of indications Cytokinetics’ drug candidates and potential drug candidates may target. For further information regarding these and other risks related to Cytokinetics’ business, investors should consult Cytokinetics’ filings with the Securities and Exchange Commission, particularly under the caption “Risk Factors” in Cytokinetics’ Annual Report on Form 10-K for the year 2022. Forward-looking statements are not guarantees of future performance, and Cytokinetics’ actual results of operations, financial condition and liquidity, and the development of the industry in which it operates, may differ materially from the forward-looking statements contained in this press release. Any forward-looking statements that Cytokinetics makes in this press release speak only as of the date of this press release. Cytokinetics assumes no obligation to update its forward-looking statements whether as a result of new information, future events or otherwise, after the date of this press release.

CYTOKINETICS® and the CYTOKINETICS and C-shaped logo are registered trademarks of Cytokinetics in the U.S. and certain other countries.

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Contact:

Cytokinetics

Diane Weiser

Senior Vice President, Corporate Communications, Investor Relations

(415) 290-7757