Nyxoah SA美股招股说明书(2025-11-17版)

1,215,964 Ordinary Shares We are offering 1,215,964 of our ordinary shares pursuant to this prospectus supplement. Our ordinaryshares are listed on The Nasdaq Global Market, or Nasdaq, under the symbol “NYXH” and on EuronextBrussels under the symbol “NYXH.” On November12, 2025, the last reported sale price of our ordinaryshares on Nasdaq was $5.68 per ordinary share, and the last reported sales price of our ordinary shares onEuronext was €4.85 per ordinary share. Our business and an investment in our ordinary shares involve significant risks. These risks are describedunder the section titled “Risk Factors” beginning on pageS-8of this prospectus supplement and in thedocuments incorporated by reference into this prospectus supplement and the accompanying prospectus. Neither the Securities and Exchange Commission nor any state securities commission has approved ordisapproved of these securities or passed upon the accuracy or adequacy of this prospectus supplement or theaccompanying prospectus. Any representation to the contrary is a criminal offense. The ordinary shares are being sold directly to the investors pursuant to a securities purchase agreementdated November13, 2025. The ordinary shares are being offered directly to investors without a placement agent or underwriter.We are not paying underwriting discounts or commissions in connection with the offering. The grossproceeds to us before expenses will be approximately $5.6million. We estimate the total expenses of thisoffering will be approximately $0.1 million. The date of this prospectus supplement is November13, 2025. TABLE OF CONTENTS PROSPECTUS SUPPLEMENT ABOUT THIS PROSPECTUS SUPPLEMENTS-iiPRESENTATION OF FINANCIAL INFORMATIONS-iiiPROSPECTUS SUPPLEMENT SUMMARYS-1THE OFFERINGS-7RISK FACTORSS-8SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTSS-10USE OF PROCEEDSS-12DIVIDEND POLICYS-13CAPITALIZATIONS-14DILUTIONS-15MATERIAL UNITED STATES FEDERAL INCOME AND BELGIAN TAX CONSIDERATIONSS-16PLAN OF DISTRIBUTIONS-33LEGAL MATTERSS-34EXPERTSS-34ENFORCEMENT OF JUDGMENTSS-34WHERE YOU CAN FIND MORE INFORMATIONS-36INCORPORATION OF DOCUMENTS BY REFERENCES-37 PROSPECTUS ABOUT THIS PROSPECTUS1PROSPECTUS SUMMARY2RISK FACTORS4SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS5CAPITALIZATION7USE OF PROCEEDS8PLAN OF DISTRIBUTION9DESCRIPTION OF SHARE CAPITAL11DESCRIPTION OF DEBT SECURITIES25DESCRIPTION OF WARRANTS31DESCRIPTION OF RIGHTS32DESCRIPTION OF UNITS34EXPENSES35LEGAL MATTERS36EXPERTS36ENFORCEMENT OF LIABILITIES36WHERE YOU CAN FIND MORE INFORMATION37INCORPORATION OF DOCUMENTS BY REFERENCE38 ABOUT THIS PROSPECTUS SUPPLEMENT This prospectus supplement and the accompanying prospectus are part of a registration statement thatwe filed with the Securities and Exchange Commission, or SEC, utilizing a “shelf” registration process onDecember22, 2022, and was declared effective by the SEC on January6, 2023. Before buying any of the ordinary shares that we are offering, we urge you to carefully read thisprospectus supplement and accompanying prospectus and all of the information incorporated by referenceherein and therein, as well as the additional information described under the headings “Where You Can FindMore Information” and “Incorporation of Documents by Reference.” These documents contain importantinformation that you should consider when making your investment decision. We provide information to you about this offering of our ordinary shares in two separate documentsthat are bound together: (1)this prospectus supplement, which describes the specific details regarding thisoffering; and (2)the accompanying base prospectus, which provides general information, some of whichmay not apply to this offering. Generally, when we refer to this “prospectus,” we are referring to bothdocuments combined. If information in this prospectus supplement is inconsistent with the accompanyingbase prospectus, you should rely on this prospectus supplement. To the extent there is a conflict between theinformation contained in this prospectus supplement, on the one hand, and the information contained in anydocument incorporated by reference in this prospectus supplement, on the other hand, you should rely onthe information in this prospectus supplement. If any statement in one of these documents is inconsistentwith a statement in another document having a later date - for example, a document incorporated byreference in this prospectus supplement - the statement in the document having the later date modifies orsupersedes the earlier statement. You should rely only on the information contained in or incorporated by reference in this prospectussupplement and any related free writing prospectus filed by us with the SEC. We have not authorizedanyone to provide you with different information. If anyone provides you with different or inconsistentinformation, you should not rely on it. This prospectus supplement does not constitute an offer to sell or thesolicitation of an offer to buy any