Shuttle Pharmaceuticals Holdings Inc美股招股说明书(2025-02-27版)

Up to 1,464,268 Shares of Common Stock Issuable Upon Conversion of 14.5% Senior Secured Convertible NotesUp to 329,461 Shares of Common Stock Issuable Upon Exercise of Warrants This prospectus supplement No. 1 updates, amends and supplements the prospectus dated January 23, 2025 (as supplemented or amended fromtime to time, the “Prospectus”), which forms a part of our Registration Statement on Form S-1, as amended (Registration No. 333-284286). This prospectus supplement is being filed to update, amend and supplement the information in the Prospectus with the information contained inour Annual Report on Form 10-K for the fiscal year ended December 31, 2024, filed with the Securities and Exchange Commission (the“Commission”) on February 26, 2025 (the “Annual Report”), and a consent from the auditor, Forvis Mazars, LLP, to include their audit report fromthe Annual Report (the “Auditors’ Consent”). Accordingly, we have attached the Annual Report and the Auditors’ Consent to this prospectussupplement. The Prospectus and this prospectus supplement relate to the resale from time to time of (i) up to 1,464,268 shares of common stock underlying$831,579 in convertible notes (the “Convertible Notes”), which represents 200% of the maximum number of shares of common stock issuable uponconversion of the Convertible Notes, and (ii) 329,461 shares of common stock issuable upon exercise of warrants (the “Warrants”), each of whichwere issued in an October 2024 private placement to the selling stockholders named in the Prospectus (the aggregate 1,793,729 shares of commonstock being registered that underly the Convertible Notes and Warrants, together, the “Shares”). In compliance with Nasdaq Rule 5635(e), theCompany will not issue more than 19.99% of the Company’s common stock issuable under the Convertible Notes, calculated as of October 21, 2024,without first obtaining stockholder approval. You should read this prospectus supplement in conjunction with the Prospectus, including any amendments or supplements to it. This prospectussupplement is qualified by reference to the Prospectus, except to the extent that the information provided by this prospectus supplement supersedesinformation contained in the Prospectus. This prospectus supplement is not complete without and may not be delivered or used except in conjunctionwith, the Prospectus, including any amendments or supplements to it. You should keep this prospectus supplement with your Prospectus for futurereference. Our common stock is listed on the Nasdaq Capital Market under the symbol “SHPH.” On February 26, 2025, the closing price of our commonstock was $0.60. Weare an“emerging growth company”under federal securities laws and are subject to reduced public company reportingrequirements. Investing in our securities involves a high degree of risk. See the section entitled “Risk Factors” beginning on page 13 of theProspectus, and under similar headings in any amendments or supplements to the Prospectus, and beginning on page 21 of our AnnualReport on Form 10-K contained herein. Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities ordetermined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense. The date of this prospectus supplement is February 27, 2025. UNITED STATESSECURITIES AND EXCHANGE COMMISSIONWashington, D.C. 20549 FORM 10-K (Mark One) ☒ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2024 or ☐TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from ______________ to ______________ Commission file number: 001-41488 Shuttle Pharmaceuticals Holdings, Inc.(Exact name of registrant as specified in its charter) Delaware82-5089826State or other jurisdiction of(I.R.S. Employer 401 Professional Drive, Suite 260Gaithersburg, MD 20879(Address of principal executive offices) (Zip Code) (240) 403-4212Registrant’s telephone number, including area code Securities registered pursuant to Section 12(b) of the Act: Securities registered pursuant to section 12(g) of the Act: NONE Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act. Yes☐No☒ Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the Act. Yes☐No☒ Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to suchfiling requirements for the past 90 days. Yes☒No☐ Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be s