CYTK: Other company developments

Item 8.01 Other Events. On August 28, 2026, Cytokinetics, Incorporated issued a press release announcing its presentation of the full results of ACACIA-HCM at the European Society of Cardiology (ESC) Congress 2026 and published in the New England Journal of Medicine. The full text of the press release issued in connection with this announcement is incorporated herein as Exhibit 99.1 to this Current Report on Form 8-K. Item 9.01 Financial Statements and Exhibits. (d) Exhibits 99.1 Press Release dated August 28, 2026 104 The cover page of this report has been formatted in Inline XBRL SIGNATURES Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized. CYTOKINETICS, INCORPORATED Date: August 28, 2026 By: /s/ John O. Faurescu John O. Faurescu SVP, Deputy General Counsel & Secretary