塞德斯医疗美股招股说明书(2026-04-02版)

10,345,000 Shares of Common Stock We are offering 10,345,000 shares of our common stock in this offering. Our common stock is listed on the Nasdaq Capital Market (“Nasdaq”) under the symbol “CLDX.” Thelast reported sale price of our common stock on April1, 2026 was $31.26 per share. Investing in our common stock involves a high degree of risk. Before buying shares of our common stock,you should carefully consider the risk factors described in “Risk Factors” beginning on pageS-8of thisprospectus supplement and in the risks discussed under similar headings in the documents incorporated byreference into this prospectus supplement, the accompanying prospectus and any free writing prospectus thatwe have authorized for use in connection with this offering. Neither the Securities and Exchange Commission nor any state securities commission has approved ordisapproved of these securities or passed upon the adequacy or accuracy of this prospectus supplement or theaccompanying prospectus. Any representation to the contrary is a criminal offense. (1)See the section entitled “Underwriting” beginning on pageS-12for a description of the compensationpayable to the underwriters. We have granted to the underwriters an option for a period of 30days to purchase up to an additional1,551,750 shares of our common stock from us at the public offering price set forth above, less theunderwriting discounts and commissions. The underwriters expect to deliver the shares of common stock against payment on or aboutApril6,2026. Joint Bookrunning Managers Leerink PartnersTD CowenGuggenheim SecuritiesCantor Co-Lead Managers LifeSci CapitalH.C. Wainwright & Co. The date of this prospectus supplement is April 1, 2026. TABLE OF CONTENTS PAGEProspectus SupplementABOUT THIS PROSPECTUS SUPPLEMENTS-1FORWARD-LOOKING STATEMENTSS-3PROSPECTUS SUPPLEMENT SUMMARYS-5THE OFFERINGS-7RISK FACTORSS-8USE OF PROCEEDSS-10DILUTIONS-11UNDERWRITINGS-12LEGAL MATTERSS-17EXPERTSS-17WHERE YOU CAN FIND MORE INFORMATIONS-17INCORPORATION OF CERTAIN DOCUMENTS BY REFERENCES-18ProspectusABOUT THIS PROSPECTUS1PROSPECTUSSUMMARY2SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS3RISK FACTORS4USE OF PROCEEDS5SELLING SECURITYHOLDERS6DESCRIPTIONS OF SECURITIES WE MAY OFFER7DESCRIPTION OF COMMON STOCK8DESCRIPTION OF PREFERRED STOCK9DESCRIPTION OF WARRANTS12DESCRIPTION OF DEPOSITARY SHARES14DESCRIPTION OF UNITS15PLAN OF DISTRIBUTION16LEGAL MATTERS18EXPERTS18WHERE YOU CAN FIND MORE INFORMATION18INCORPORATION OF CERTAIN DOCUMENTS BY REFERENCE19 ABOUT THIS PROSPECTUS SUPPLEMENT This document is in two parts. The first part is this prospectus supplement, which describes the specificterms of this offering of common stock and also adds to and updates information contained in theaccompanying prospectus and the documents incorporated by reference in this prospectus supplement andthe accompanying prospectus. The second part, the accompanying prospectus, provides more generalinformation, some of which may not apply to this offering. Generally, when we refer to this prospectussupplement, we are referring to both parts of this document combined. To the extent there is a conflictbetween the information contained in this prospectus supplement and the information contained in theaccompanying prospectus or any document incorporated by reference that was filed with the U.S. Securitiesand Exchange Commission (the “SEC”) before the date of this prospectus supplement, you should rely onthe information in this prospectus supplement; provided that if any statement in one of these documents isinconsistent with a statement in another document having a later date — for example, a documentincorporated by reference in the accompanying prospectus — the statement in the document having the laterdate modifies or supersedes the earlier statement. We further note that the representations, warranties and covenants made by us in any agreement that isfiled as an exhibit to any document that is incorporated by reference herein were made solely for the benefitof the parties to such agreement, including, in some cases, for the purpose of allocating risk among theparties to such agreements, and should not be deemed to be a representation, warranty or covenant to you.Moreover, such representations, warranties or covenants were accurate only as of the date when made.Accordingly, such representations, warranties and covenants should not be relied on as accuratelyrepresenting the current state of our affairs. Neither we nor the underwriters have authorized anyone to provide information different from thatcontained in this prospectus supplement and the accompanying prospectus, including any free writingprospectus that we have authorized for use in connection with this offering. When you make a decisionabout whether to invest in our common stock, you should not rely upon any information other than theinformation in this prospectus supplement and the accompanying prospectus, including any free writingprospectus