Windtree Therapeutics Inc美国股票招股说明书（2025年4月25日版）

Up to 31,247,383 Shares of Common Stock This prospectus relates to (i) the offer and resale or other disposition from time to time by certain of the sellingstockholders identified in this prospectus of (a) up to 8,053,565 shares of our common stock (the “ConversionShares”), par value $0.001 per share, issuable upon the conversion of shares of our Series C convertiblepreferred stock, par value $0.001 per share (the “Series C Preferred Stock”), and (b) up to 440,583 shares (the“Subject Warrant Shares”) of our common stock issuable upon the exercise of certain warrants (the “SubjectWarrants”); and (ii) the offer and resale or other disposition from time to time by certain of the sellingstockholders identified in this prospectus of up to 919,132 shares of our common stock (the “Subject NoteShares”) that may be issued upon the conversion of the 20% OID Senior Secured Promissory Notes (the “SubjectNotes”) that we issued on April 4, 2025. This prospectus also relates to the resale from time to time of shares ofour common stock issued pursuant to the equity line of credit (“ELOC”) established under the a common stockpurchase agreement (the “ELOC Purchase Agreement”) that we entered into with Seven Knots, LLC (“SevenKnots”) on June 26, 2024 of our common stock in an offering amount of up to $23.8 million, representing21,834,103 shares of common stock based on the average of the high and low reported prices of our commonstock as reported on The Nasdaq Capital Market on April 17, 2025, of $1.149 less a 5% discount, that we mayissue to Seven Knots under the ELOC Purchase Agreement (the “ELOC Shares”). We are registering the resale of the shares of common stock covered by this prospectus pursuant to the sellingstockholders’ registration rights under (i) the Registration Rights Agreement, dated July 22, 2024, by and amongus and the PIPE Tranche I Investors (as defined below), (ii) the Registration Rights Agreement, dated July 29,2024, by and among us and the PIPE Tranche II Investors (as defined below), (iii) the Subject Notes, and (iv) theELOC Purchase Agreement. We will not receive any proceeds from the sale by the selling stockholders of their shares of common stock.However, we may receive (i) up to approximately $0.2 million from the exercise of the Subject Warrants forcash; and (ii) up to $23.8 million from sales of ELOC Shares to Seven Knots. We have received aggregate grossproceeds of $11.2 million from the issuance of 342,900 shares of common stock under the ELOC PurchaseAgreement through the date of this prospectus. We have agreed to bear the expenses in connection with theregistration of the resale of the shares of common stock to be offered by this prospectus by the sellingstockholders except for any underwriting discounts and commissions or transfer taxes relating to the sale ofcommon stock, which will be borne by the selling stockholders. Our registration of the shares on behalf of the selling stockholders does not mean that any of the sellingstockholders will offer or sell any of their shares of common stock. We cannot predict when, or in what amounts,the selling stockholders may sell their shares of common stock. Sales of the shares of common stock by theselling stockholders may occur in one or more transactions at fixed prices, at market prices prevailing at the timeof sale, at prices related to prevailing market prices, at negotiated prices, and/or at varying prices determined atthe time of sale. The selling stockholders may sell their shares of common stock directly or to or throughunderwriters, broker-dealers or agents, who may receive compensation in the form of discounts, concessions orcommissions from the selling stockholders, the purchasers of the shares, or both. We provide more information about how the selling stockholders may sell or otherwise dispose of their shares of common stock in the sectionof this prospectus titled “Plan of Distribution.” Table of Contents Our common stock is traded on The Nasdaq Capital Market under the symbol “WINT”. The last reported saleprice of our common stock on The Nasdaq Capital Market on April 24, 2025 was $1.17 per share. On February 14, 2025, we filed a certificate of amendment to the Company’s Amended and Restated Certificateof Incorporation with the Secretary of State of the State of Delaware to effectuate a 1-for-50 reverse stock split(the “Reverse Stock Split”) of the outstanding shares of the Company’s common stock. Our stockholderspreviously approved the Reverse Stock Split and granted the Company’s board of directors the authority todetermine the exact split ratio and when to proceed with the Reverse Stock Split at the Company’s specialmeeting of stockholders held on February 3, 2025. The Reverse Stock Split became effective on February 20,2025 at 5:00 p.m., Eastern Time and our common stock began trading on The Nasdaq Capital Market on aReverse Stock Split-adjusted basis on February 21, 2025 at market open under the existing ticker symbol,“WIN