Changes in Registrant’s Certifying Accountant. Dismissal of Independent Registered Public Accounting Firm. On October 16, 2026, the Audit Committee (the “Audit Committee”) of the Board of Directors (the “Board”) of Shuttle Pharmaceuticals Holdings, Inc. (the “Company”), and the full Board, approved the dismissal of Forvis Mazars, LLP (“Forvis Mazars”) as the Company’s independent registered public accounting firm, effective following the filing of the Company’s Quarterly Report on Form 10-Q f…

disclosing, among other things, that the Company issued pre-funded warrants (the “Pre-Funded Warrants”) to purchase an aggregate of approximately 16,932,508 shares of Common Stock, which number actually represents the maximum number of Pre-Funded Warrants that may be issued upon the satisfaction of all conditions to issuance, and not the number of Pre-Funded Warrants that were issued as of September 9, 2026. The Company hereby amends the Form 8-K to reflect that, as of September 9, 2026, the…

Unregistered Sales of Equity Securities. As previously disclosed, on September 9, 2026, Shuttle Pharmaceuticals Holdings, Inc. (the “Company”) held a Special Meeting of Stockholders (the “Meeting”) pursuant to which, among other things, the stockholders of the Company approved the issuance of securities of the Company as described in that Definitive Proxy Statement on Schedule 14A filed by the Company with the U.S. Securities and Exchange Commission (the “SEC”) on August 13, 2026, as suppleme…

Entry Into A Material Definitive Agreement. On August 31, 2026, Shuttle Pharmaceuticals Holdings, Inc. (the “Company”) and United Dogecoin Inc. (“United Dogecoin”), a wholly-owned subsidiary of the Company as a result of the consummation on May 6, 2026 of that certain transaction contemplated by the Agreement and Plan of Merger dated April 30, 2026 (the “Merger Agreement”), by and among the Company, United Dogecoin and Shuttle Merger Sub, Inc., entered into a First Amendment to Merger Agreeme…

Notice of Delisting or Failure to Satisfy a Continued Listing Rule or Standard; Transfer of Listing. On August 28, 2026, Shuttle Pharmaceuticals Holdings, Inc. (the “Company”) received a notification letter (the “Notice”) from the Listing Qualifications Department of The Nasdaq Stock Market LLC (“Nasdaq”) indicating that, as a result of the Company’s delay in filing its Quarterly Report on Form 10-Q for the period ended June 30, 2026 (the “Form 10-Q”) with the Securities and Exchange Commissi…

of the Original 8-K, and incorporated by reference into

of Form 8-K. This Current Report on Form 8-K/A amends the Original 8-K solely to amend and include Item 2.01, Item 9.01(a) and Item 9.01(b), to reflect that the transactions contemplated by the Merger Agreement are not significant and accordingly the historical and pro forma financial information required under those items are not applicable. There are no other modifications or updates to any of the information made in the Original 8-K.

of Form 8-K, the information regarding the Reverse Stock Split (as defined below) contained in

Material Modification to Rights of Security Holders. To the extent required by

Completion of Acquisition or Disposition of Assets. The disclosure required by this Item in connection with the Closing and included in

Co-Chief Executive Officer — Ryan Trasolini: Appointment of Ryan Trasolini as Co-Chief Executive Officer in connection with the Merger.

Unregistered Sales of Equity Securities. The disclosure set forth above in

Entry Into A Material Definitive Agreement. Merger Agreement General Description of the Merger Agreement On May 6, 2026 (the “ Closing Date ”), Shuttle Pharmaceuticals Holdings, Inc., a Delaware corporation (“ Shuttle ” or “ Acquiror ”), completed its previously announced merger pursuant to an Agreement and Plan of Merger (the “ Merger Agreement ”), entered into on April 30, 2026 by and among the Acquiror, Shuttle Merger Sub, Inc., a Delaware corporation and a wholly owned subsidiary of Shutt…

by reference. The issuance of the Merger Consideration and the offer, sale and issuance of the Securities have not been registered under the Securities Act of 1933, as amended (the “ Securities Act ”), in reliance upon the exemption from registration provided by Section 4(a)(2) of the Securities Act.

Entry Into A Material Definitive Agreement. Merger Agreement General Description of the Merger Agreement On April 30, 2026, Shuttle Pharmaceuticals Holdings, Inc., a Delaware corporation (“ Shuttle ” or “ Acquiror ”), entered into an Agreement and Plan of Merger (the “ Merger Agreement ”) with Shuttle Merger Sub, Inc., a Delaware corporation and a wholly owned subsidiary of Shuttle (“ Merger Sub ”) and United Dogecoin Inc., a Delaware corporation (the “ Company ”). The transactions contemplat…

Entry into a Material Definitive Agreement. On March 5, 2026, Shuttle Pharmaceuticals Holdings, Inc. (the “Company”) priced its recently announced public offering (the “Offering”) of 2,238,800 shares of the Company’s common stock par value $0.00001 per share (the “Common Stock”), and pre-funded warrants to purchase up to 4,761,200 shares of Common Stock (the “Pre-Funded Warrants”) for aggregate gross proceeds of approximately $3.5 million, before deducting placement agent fees and other offer…

Results of Operations and Financial Condition. On February 11, 2026, Shuttle Pharmaceuticals Holdings, Inc. (the “Company”) filed a registration statement on Form S-1 disclosing certain preliminary estimated unaudited financial results for the full year ended December 31, 2025. The text of the disclosure of those preliminary estimated unaudited financial results is included below. Preliminary Estimated Unaudited Financial Results for the Year Ended December 31, 2025 Set forth below are prelim…

The filing details an amendment to a consulting agreement, not a management change.

Director — Sachin Pathigoda: Mr. Sachin Pathigoda resigned from his position as a director of the Board.

Entry into a Material Definitive Agreement. On December 23, 2025 (the “ Effective Date ”), Shuttle Pharmaceuticals Holdings, Inc. (the “ Company ”) entered into a First Amendment (the “ Amendment ”) to Asset Purchase Agreement (the “ Agreement ”) with 1563868 B.C. Ltd., a Canadian limited corporation and the Company’s wholly owned subsidiary (“ Purchaser ”), 1542770 BC Ltd., a Canadian limited corporation (“ Seller ”), and ZhiTian (Andy) Zhang, an individual residing in Vancouver, Canada (“ S…

Unregistered Sales of Equity Securities. The information set forth under in

Chief Financial Officer — Timothy Lorber: Mr. Lorber resigned as Chief Financial Officer and will be replaced by Christopher Cooper, who is currently the Interim Chief Executive Officer.

Entry into a Material Definitive Agreement. On November 20, 2025 (the “ Closing Date ”), Shuttle Pharmaceuticals Holdings, Inc. (the “Company”) entered into an Asset Purchase Agreement (the “ Agreement ”) with 1563868 B.C. Ltd., a Canadian limited corporation and the Company’s wholly owned subsidiary (“ Purchaser ”), 1542770 BC Ltd., a Canadian limited corporation (“ Seller ”) and Zhitian (Andy) Zhang, an individual residing in Vancouver, Canada (“ Seller Guarantor ”). Pursuant to the terms a…

Completion of Acquisition or Disposition of Assets. The disclosure set forth under

Unregistered Sales of Equity Securities. The information set forth under in