Shuttle Pharmaceuticals Holdings, Inc.

S-11 forms-1.htm S-1

As filed with the Securities and Exchange Commission on November 18, 2025

Registration No. 333-

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM S-1

REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933

SHUTTLE PHARMACEUTICALS HOLDINGS, INC.

(Exact name of registrant as specified in its charter)

401 Professional Drive, Suite 260

Gaithersburg, MD 20879 (240) 430-4212

(Address, including zip code, and telephone number,

including area code, of registrant’s principal executive offices)

Christopher Cooper

Interim Chief Executive Officer

Shuttle Pharmaceuticals Holdings, Inc.

401 Professional Drive, Suite 260

Gaithersburg, MD 20879 (240) 430-4212

(Name, address, including zip code, and telephone number,

including area code, of agent for service)

Copies to:

**David E. Danovitch, Esq.

Aaron M. Schleicher, Esq.

Sullivan & Worcester LLP

1251 Avenue of the Americas, 19 th Floor

New York, NY 10020

(212) 660-3060

From time to time after this registration statement becomes effective.

(Approximate date of commencement of proposed sale to the public)

If any of the securities being registered on this Form are to be offered on a delayed or continuous basis pursuant to Rule 415 under the Securities Act of 1933 check the following box. ☒

If this Form is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. ☐

If this Form is a post-effective amendment filed pursuant to Rule 462(c) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. ☐

If this Form is a post-effective amendment filed pursuant to Rule 462(d) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. ☐

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, smaller reporting company, or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company,” and “emerging growth company” in Rule 12b-2 of the Exchange Act.

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 7(a)(2)(B) of the Securities Act. ☐

The Registrant hereby amends this Registration Statement on such date or dates as may be necessary to delay its effective date until the Registrant shall file a further amendment which specifically states that this Registration Statement shall thereafter become effective in accordance with Section 8(a) of the Securities Act of 1933, as amended, or until the Registration Statement shall become effective on such date as the Securities and Exchange Commission, acting pursuant to Section 8(a), may determine.

The information in this preliminary prospectus is not complete and may be changed. These securities may not be sold until the registration statement filed with the Securities and Exchange Commission is effective. This preliminary prospectus is not an offer to sell nor does it seek an offer to buy these securities in any state or other jurisdiction where the offer or sale is not permitted.

Shuttle Pharmaceuticals Holdings, Inc.

625,156 Shares of Common Stock

Pursuant to this prospectus, the selling stockholder identified herein is offering on a resale basis 625,156 shares of common stock of Shuttle Pharmaceuticals Holdings, Inc., consisting of 625,156 shares of common stock issuable upon exercise of a pre-funded warrant, exercisable at a nominal exercise price per share of $0.001, without expiration. The pre-funded warrant was issued to the selling stockholder in connection with a private placement we completed on November 4, 2025. We will not receive any of the proceeds from the sale by the selling stockholder of the shares.

The selling stockholder may sell or otherwise dispose of the shares covered by this prospectus in a number of different ways and at varying prices. We provide more information about how the selling stockholder may sell or otherwise dispose of the shares covered by this prospectus in the section entitled “Plan of Distribution” on page 8. Discounts, concessions, commissions and similar selling expenses attributable to the sale of shares covered by this prospectus will be borne by the selling stockholder. We will pay all expenses (other than discounts, concessions, commissions and similar selling expenses) relating to the registration of the shares with the Securities and Exchange Commission, or the SEC.

You should carefully read this prospectus, together with the documents we incorporate by reference, before you invest in our common stock.

Our common stock is listed on The Nasdaq Capital Market under the symbol “SHPH.” On November 17, 2025, the last reported sale price for our common stock was $1.92 per share.

Investing in our common stock involves substantial risk. Please read “Risk Factors” beginning on page 6 of this prospectus and in the documents we incorporate by reference.

Neither the SEC nor any state securities commission has approved or disapproved of these securities or passed upon the accuracy or adequacy of this prospectus. Any representation to the contrary is a criminal offense.

The date of this prospectus is ____, 2025

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