Disc Medicine Inc美股招股说明书(2025-10-21版)

2,916,668 Shares of Common StockPre-FundedWarrants to Purchase 59,523 Shares of Common Stock We are offering 2,619,049 shares of our common stock and, in lieu of common stock to certain investors that so choose,pre-fundedwarrants to purchase 59,523 shares ofcommon stock in this offering. The selling stockholder identified in this prospectus supplement (the “selling stockholder”) is offering 297,619 shares of our commonstock. We will not receive any proceeds from the sale of our common stock by the selling stockholder. Our common stock is listed on the Nasdaq Global Market under the symbol “IRON.” On October20, 2025, the closing sale price of our common stock on the Nasdaq The purchase price of eachpre-fundedwarrant will equal the price per share at which shares of our common stock are being sold to the public in this offering, minus$0.0001, which is the exercise price of eachpre-fundedwarrant. Thepre-fundedwarrants do not expire, and eachpre-fundedwarrant will be exercisable at any time afterthe date of issuance, subject to an ownership limitation and in some cases clearance under the Hart-Scott-Rodino Antitrust Improvements Act of 1976, as amended, or theHSR Act. This prospectus supplement also relates to the offering of the shares of common stock issuable upon exercise of suchpre-fundedwarrants. There is no established public trading market for thepre-fundedwarrants, and we do not expect a market to develop. We do not intend to list thepre-fundedwarrants onthe Nasdaq Global Market or any other national securities exchange or nationally recognized trading system. Investing in our securities involves a high degree of risk. Please read “Risk Factors” beginning on pageS-7of this prospectussupplement, page10 and page 7 in the accompanying prospectuses, and under similar headings in the documents that areincorporated by reference into this prospectus supplement concerning factors you should carefully consider before investing in oursecurities. (1)See the section titled “Underwriting” beginning on pageS-27for a description of the compensation payable to the underwriters. The selling stockholder has granted the underwriters an option for a period of 30 days to purchase up to an additional 446,428 shares of our common stock at the publicoffering price, less the underwriting discounts and commissions. We will not receive any proceeds from the sale of our common stock by the selling stockholder. See“Selling Stockholder” beginning on pageS-16. Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities, or passed upon the adequacyor accuracy of this prospectus supplement or the accompanying prospectuses. Any representation to the contrary is a criminal offense. The underwriters expect to deliver the shares of common stock andpre-fundedwarrants against payment therefor on or about October 22, 2025. Jefferies Cantor Co-Managers H.C. Wainwright & Co. Table of Contents TABLE OF CONTENTSPROSPECTUS SUPPLEMENT About this Prospectus SupplementCautionary Statement Regarding Forward-Looking StatementsProspectus Supplement SummaryRisk FactorsDividend PolicyUse of ProceedsDilutionSelling StockholderDescription ofPre-FundedWarrantsMaterial U.S. Federal Income Tax Consequences for Investors in Common StockUnderwritingLegal MattersExpertsWhere You Can Find More InformationIncorporation of Certain Information by Reference PROSPECTUS DATED AUGUST 8, 2024 ABOUT THIS PROSPECTUSWHERE YOU CAN FIND MORE INFORMATIONINCORPORATION OF CERTAIN INFORMATION BY REFERENCESPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTSABOUT THE COMPANYRISK FACTORS USE OF PROCEEDSDIVIDEND POLICYGENERAL DESCRIPTION OF SECURITIESDESCRIPTION OF CAPITAL STOCKDESCRIPTION OF DEBT SECURITIESDESCRIPTION OF WARRANTSDESCRIPTION OF UNITSPLAN OF DISTRIBUTIONLEGAL MATTERSEXPERTS PROSPECTUS DATED JANUARY 24, 2023 ABOUT THIS PROSPECTUSCAUTIONARY STATEMENT REGARDING FORWARD-LOOKING STATEMENTSTHE COMPANYTHE OFFERINGRISK FACTORSSELECTED FINANCIAL DATA USE OF PROCEEDSDESCRIPTION OF CAPITAL STOCKSELLING STOCKHOLDERSPLAN OF DISTRIBUTIONLEGAL MATTERSEXPERTS Table of Contents ABOUT THIS PROSPECTUS SUPPLEMENT This prospectus supplement is part of an automatic shelf registration statement on FormS-3(FileNo.333-281359)that we filed with theSecurities and Exchange Commission, or SEC, on August8, 2024 as a “well-known seasoned issuer” as defined in Rule 405 of the Securities Act andpart of a resale registration statement on FormS-3(FileNo.333-269270)that we filed with the SEC on January17, 2023 covering the shares beingoffered by the selling stockholder. This document is in two parts. The first part is this prospectus supplement, which describes the specific terms of this offering of common stockandpre-fundedwarrants. The second part is the accompanying prospectuses, which provide more general information, some of which may not apply tothis offering. The information included or incorporated by re