Cytokinetics Inc美股招股说明书(2026-05-07版)

Common stock We are offering 9,859,155 shares of our common stock pursuant to this prospectus supplement and the accompanying prospectus. Our commonstock is listed on the Nasdaq Global Select Market under the trading symbol “CYTK.” On May4, 2026, the last reported sale price of our commonstock on the Nasdaq Global Select Market was $66.05 per share. The underwriters have agreed to purchase shares of our common stock from us at a price of $71.00 per share, which will result in approximately$700 million of proceeds to us before expenses. The underwriters may offer the shares of our common stock from time to time for sale in one ormore transactions on the Nasdaq Global Select Market, in the over-the-counter market, through negotiated transactions or otherwise at marketprices prevailing at the time of sale, at prices related to prevailing market prices or at negotiated prices. For additional information regardingunderwriting compensation, see “Underwriting.” Investing in our common stock involves a high degree of risk. See “RiskFactors” beginning on page S-4 and in thedocuments incorporated by reference into this prospectus supplement before investing in our common stock. We have granted the underwriters an option to purchase 1,478,873 additional shares of our common stock at the same price set forth above, within 30days from the date of this prospectus supplement. Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or passed uponthe accuracy or adequacy of this prospectus supplement or the accompanying prospectus. Any representation to the contrary is a criminal offense. The underwriters expect to deliver the shares of common stock against payment on or about May8, 2026. Joint Book-Running Managers Table of Contents Prospectus ABOUT THIS PROSPECTUS SUPPLEMENTPROSPECTUS SUPPLEMENT SUMMARYRISK FACTORSSPECIAL NOTE REGARDING FORWARD-LOOKINGSTATEMENTSUSE OF PROCEEDSDILUTIONUNDERWRITINGLEGAL MATTERSEXPERTSWHERE YOU CAN FIND ADDITIONAL INFORMATIONINCORPORATION OF CERTAIN INFORMATION BYREFERENCE PageS-iiS-1S-4S-6S-8S-9S-11S-22S-22S-23S-24PageABOUT THIS PROSPECTUSiiPROSPECTUS SUMMARY1RISK FACTORS5SPECIAL NOTE REGARDING FORWARD-LOOKINGSTATEMENTS6USE OF PROCEEDS8DESCRIPTION OF CAPITAL STOCK9DESCRIPTION OF DEBT SECURITIES13DESCRIPTION OF WARRANTS20LEGAL OWNERSHIP OF SECURITIES22SELLING SECURITYHOLDERS25PLAN OF DISTRIBUTION26LEGAL MATTERS28EXPERTS28WHERE YOU CAN FIND MORE INFORMATION29INCORPORATION OF CERTAIN INFORMATION BYREFERENCE30 About This Prospectus Supplement This prospectus supplement is a part of a registration statement that we have filed on Form S-3 with the U.S. Securities and ExchangeCommission (the “SEC”), utilizing a “shelf” registration process. By using a shelf registration statement, we may offer shares of our common stock fromtime to time under this prospectus supplement and on terms to be determined by market conditions at the time of the offering. Before buying any of thecommon stock that we are offering, we urge you to carefully read this prospectus supplement, together with the information incorporated by reference asdescribed under the headings “Where You Can Find Additional Information” and “Incorporation of Certain Information by Reference” in this prospectussupplement. These documents contain important information that you should consider when making your investment decision. This document consists of two parts. The first part is this prospectus supplement, which describes the specific terms of this offering and also addsto and updates the information contained in the accompanying prospectus and the documents incorporated by reference into this prospectus supplementand the accompanying prospectus. The second part, the accompanying prospectus, gives more general information, some of which may not apply to thisoffering. To the extent there is a conflict between the information contained in this prospectus supplement, on the one hand, and the informationcontained in the accompanying prospectus or any document incorporated by reference, on the other hand, you should rely on the information in thisprospectus supplement. Generally, when we refer to the prospectus, we are referring to this prospectus supplement and the accompanying prospectuscombined. We have not, and the underwriters have not, authorized anyone else to provide you with information that is in addition to or different from thatcontained or incorporated by reference in this prospectus supplement and the accompanying prospectus, along with the information contained in anypermitted free writing prospectuses we have authorized for use in connection with this offering. We take, and the underwriters take, no responsibility for,and can provide no assurance as to the reliability of, any other information that others may give you. We are offering to sell, and seeking offers to buy,shares of our common stock only in jurisdictions where offers and sales a