Sana Biotechnology Inc美股招股说明书(2026-04-13版)

Common Stock We are offering up to an aggregate of 15,015,014 shares of our common stock directly to the investor, Mayo Clinic, in up to two closings, to be soldpursuant to the terms and conditions of the stock purchase agreement, dated as of April10, 2026, between us and Mayo Clinic (the Stock PurchaseAgreement). In each closing, we are offering 7,507,507 shares of our common stock at a purchase price per share of $3.33. The initial closing of thisoffering (the Initial Closing) is expected to occur on or about April 15, 2026. As further described in this prospectus supplement, Mayo Clinic may elect,on or before August31, 2026, to hold the second closing of this offering (the Second Closing). This offering is being made without an underwriter or a placement agent and we are not paying underwriting discounts or commissions. Accordingly, theaggregate proceeds to us, assuming the sale of all shares in the Initial Closing and the optional Second Closing, before expenses, will be approximately$50,000,000. We estimate the total expenses of this offering will be approximately $105,000. Our common stock is listed on the Nasdaq Global Select Market under the symbol “SANA.” On April9, 2026, the last reported sale price of ourcommon stock on the Nasdaq Global Select Market was $3.12 per share. We are an “emerging growth company” as defined by the Jumpstart Our Business Startups Act of 2012, and a “smaller reporting company” as definedunder the federal securities laws and as such, have elected to comply with reduced public company reporting requirements for this prospectussupplement and the base prospectus, including the documents incorporated by reference herein and therein, and may elect to comply with reduced publiccompany reporting requirements in future filings. Our business and an investment in our common stock involve significant risks. These risks are described under the caption “Risk Factors”beginning on page S-6 of this prospectus supplement and in the documents incorporated by reference into this prospectus supplement and thebase prospectus. Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or passedupon the adequacy or accuracy of this prospectus supplement and the base prospectus. Any representation to the contrary is a criminal offense. Table of Contents TABLE OF CONTENTS Prospectus SupplementAbout this Prospectus SupplementMarket, Industry, and Other DataProspectus Supplement SummaryThe OfferingRisk FactorsOptional Second ClosingSpecial Note Regarding Forward-Looking StatementsUse of ProceedsDilutionPlan of DistributionLegal MattersExpertsWhere You Can Find More InformationInformation Incorporated by Reference ProspectusAbout this ProspectusProspectus SummaryRisk FactorsForward-Looking StatementsUse of ProceedsDescription of Capital StockDescription of Debt SecuritiesDescription of Depositary Shares Description of Warrants Description of Purchase Contracts Legal Matters Experts Where You Can Find More Information Incorporation by Reference Table of Contents ABOUT THIS PROSPECTUS SUPPLEMENT This prospectus supplement is part of an automatic shelf registration statement on FormS-3that we filed with the U.S. Securities and ExchangeCommission (SEC) as a “well-known seasoned issuer” as defined under the Securities Act of 1933, as amended (the Securities Act), including the baseprospectus therein. Under the shelf registration process, we may offer an unspecified amount of the securities described in the base prospectus from timeto time, of which this offering of shares of our common stock is a part. This prospectus supplement describes the specific terms of this offering of common stock and also adds to and updates information contained inthe base prospectus and the documents incorporated by reference into this prospectus supplement and such base prospectus. Generally, when we refer tothis prospectus, we are referring to both this prospectus supplement and the base prospectus. In this prospectus supplement, as permitted by law, we “incorporate by reference” information from other documents that we file with the SEC.This means that we can disclose important information to you from those documents which we may file with the SEC from time to time. Theinformation incorporated by reference is considered to be a part of this prospectus supplement and the base prospectus and should be read with the samecare. To the extent there is a conflict between the information contained in this prospectus supplement, on the one hand, and the information contained inany document incorporated by reference filed prior to the date of this prospectus supplement, on the other hand, you should rely on the information inthis prospectus supplement. However, if any statement in one of these documents is inconsistent with a statement in another document having a laterdate—for example, a document incorporated by reference into this prospect