UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934

Date of Report (Date of earliest event reported): May 8, 2023

SHUTTLE PHARMACEUTICALS HOLDINGS, INC.

(Exact name of registrant as specified in its charter)

One Research Court, Suite 450

Rockville, Maryland 20850

(Address Of Principal Executive Offices) (Zip Code)

240-430-4212

Registrant’s telephone Number, including Area Code

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

Securities registered pursuant to Section 12(b) of the Act:

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

Emerging growth company ☒

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Item 1.01 Entry into a Material Definitive Agreement.

Amendment to Alto Agreement

On May 10, 2023, Shuttle Pharmaceuticals Holdings, Inc., a Delaware corporation (the “Company”), entered into an amendment agreement (the “Amendment Agreement”) to the Securities Purchase Agreement, originally dated January 11, 2023 (the “SPA”), between the Company, Alto Opportunity Master Fund, SPC – Segregated Master Portfolio B (“Alto”), in its capacity as the registered holder of a $4.3 million convertible note (the “Alto Note”) and warrant to purchase 1,018,079 shares of common stock (the “Alto Warrant”) issued by the Company, and the Company’s wholly owned subsidiary, Shuttle Pharmaceuticals, Inc., as guarantor (“Shuttle Pharma”). (The Alto Note, Alto Warrant and the SPA are referred to herein as the “Transaction Documents”).

Under the Amendment Agreement, the Company and Alto amended the Transaction Documents as follows: (i) amended and restated Section 2 of the Alto Warrant so as to remove a provision that would have potentially required an adjustment to the number of warrant shares exercisable under the Warrant, (ii) stipulated that the Company would obtain majority shareholder approval to issue up to an additional $10 million in convertible notes (the “Subsequent Notes”) and warrants (the “Subsequent Warrants”) equal to 42.5% of the outstanding principal value of the Subsequent Notes, which Subsequent Note and Subsequent Warrant would be sold to Alto on substantially the same terms as the existing Alto Note and Alto Warrant (each as amended by the Amendment Agreement) and upon conversion and/or exercise would cause the potential issuance of in excess of 19.9% of the Company’s issued and outstanding stock, (iii) that, upon obtaining majority stockholder approval, the Company would file a Schedule 14C related to such potential issuance of the shares of common stock related to the potential sale of the Subsequent Notes and Subsequent Warrants to Alto within 30 calendar days of entry into the Amendment Agreement, and (iv) stipulated that Alto would release $1,500,000 in cash collateral to the Company, with $1,000,000 to be released to the Company immediately upon singing of the Amendment Agreement and $500,000 to be released upon the Company’s filing of the Schedule 14C. The Company obtained majority stockholder consent to the potential sale of the Subsequent Notes and Subsequent Warrants to Alto in advance of entry into the Amendment Agreement.

The foregoing description of the Amendment Agreement does not purport to be complete and is qualified in its entirety by reference to the full text of the Amendment Agreement, which agreement is attached hereto as Exhibit 10.1 and incorporated herein by reference.

Item 8.01. Other Events.

Award of Patent

On May 8, 2023, the Company received notice that Shuttle Pharma’s U.S. Patent Application No. 16/475,999 had been approved by the U.S. Patent and Trademark Office (“USPTO”) and that Shuttle Pharma will be issued U.S. Patent No. 11,654,157, “Methods And Compositions For Cancer Therapies That Include Delivery Of Halogenated Thymidines And Thymidine Phosphorylase Inhibitors In Combination With Radiation.” The USPTO will issue the patent on May 23, 2023, after which time the patent will be downloadable from the USPTO’s website.

Item 9.01. Financial Statements and Exhibits.

(d) Exhibits.

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.