Shuttle Pharmaceuticals Holdings, Inc.

S-11 forms-1.htm S-1

As filed with the Securities and Exchange Commission on February 10, 2026

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:

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.

PRELIMINARY PROSPECTUS

(Subject to Completion, dated February 10, 2026)

The information in this prospectus is not complete and may be changed. We may not sell these securities until the registration statement filed with Securities and Exchange Commission is effective. This prospectus is not an offer to sell these securities and is not soliciting an offer to buy these securities in any state where the offer or sale is not permitted.

SHUTTLE PHARMACEUTICALS HOLDINGS, INC.

Up to 2,229,300 Shares of Common Stock

Pre-Funded Warrants to purchase up to 2,229,300 Shares of Common Stock

We are offering up to 2,229,300 shares of our common stock, at an assumed public offering price of $1.57, which is equal to the closing price per share of our common stock on The Nasdaq Capital Market, on February 5, 2026, pursuant to this prospectus.

We are also offering to each purchaser whose purchase of shares of our common stock in this offering would otherwise result in the purchaser, together with its affiliates and certain related parties, beneficially owning more than 4.99% (or, at the election of the holder, 9.99%) of our outstanding shares of common stock immediately following the consummation of this offering, the opportunity to purchase, if the purchaser so chooses, pre-funded warrants to purchase shares of common stock, or the pre-funded warrants, in lieu of shares of common stock. Each pre-funded warrant will be exercisable for one share of our common stock. Pre-funded warrants will be exercisable upon issuance and will expire when exercised in full. The purchase price of each pre-funded warrant will equal the price per share of common stock being sold to the public in this offering, minus $0.001, and the exercise price of each pre-funded warrant will be $0.001 per share. For each pre-funded warrant that we sell, the number of shares of our common stock that we are offering will be decreased on a one-for-one basis. The pre-funded warrants will not be listed on the Nasdaq Capital Market and are not expected to trade in any market, however we anticipate that the shares of our common stock to be issued upon exercise of the pre-funded warrants will trade on the Nasdaq Capital Market. This prospectus also relates to the shares of common stock issuable upon the exercise of the pre-funded warrants.

This offering will terminate on March 6, unless we decide to terminate the offering (which we may do at any time in our discretion) prior to that date. We will have one closing for all the securities purchased in this offering. The public offering price per share (or pre-funded warrant) will be fixed for the duration of this offering.

We have engaged E.F. Hutton & Co. (“E.F. Hutton”), or the placement agent, to act as our exclusive placement agent in connection with this offering. The placement agent has agreed to use its reasonable best efforts to arrange for the sale of the securities offered by this prospectus. The placement agent is not purchasing or selling any of the securities we are offering and the placement agent is not required to arrange the purchase or sale of any specific number or dollar amount of securities. We have agreed to pay to the placement agent the placement agent fees set forth in the table below, which assumes that we sell all of the securities offered by this prospectus. Because we will deliver the securities to be issued in this offering upon our receipt of investor funds, there is no arrangement for funds to be received in escrow, trust or similar arrangement. There is no minimum offering requirement as a condition of closing of this offering. Because there is no minimum offering amount required as a condition to closing this offering, we may sell fewer than all of the securities offered hereby, which may significantly reduce the amount of proceeds received by us, and investors in this offering will not receive a refund in the event that we do not sell an amount of securities sufficient to pursue our business goals described in this prospectus. In addition, because there is no escrow account and no minimum offering amount, investors could be in a position where they have invested in our company, but we are unable to fulfill all of our contemplated objectives due to a lack of interest in this offering. Further, any proceeds from the sale of securities offered by us will be available for our immediate use, despite uncertainty about whether we would be able to use such funds to effectively implement our business plan. See the section entitled “Risk Factors” for more information. We will bear all costs associated with the offering. See “Plan of Distribution” on page 20 of this prospectus for more information regarding these arrangements.

Our common stock is listed on the Nasdaq Capital Market under the symbol “SHPH.” The closing price of our common stock on the Nasdaq Stock Market on February 5, 2026, was $1.57 per share.

All share and pre-funded warrant numbers are based on an assumed public offering price of $1.57 per share and $1.57 per pre-funded warrant. The actual public offering price per share and the actual public offering price per pre-funded warrant will be determined through negotiation among us, the placement agent and the investors in the offering based on market conditions at the time of pricing, and may be at a discount to the current market price of our common stock. Therefore, the recent market price per share of common stock used throughout this prospectus as an assumed public offering price may not be indicative of the final offering price. There is no established trading market for thepre-funded warrants, and we do not expect a market to develop. We do not intend to apply for a listing of the pre-funded warrants on any securities exchange or other nationally recognized trading system. Without an active trading market, the liquidity of the pre-funded warrants will be limited.

Investing in our securities involves a high degree of risk. These risks are described in the “Risk Factors” section on page 5 of this prospectus. You should also consider the risk factors described or referred to in any documents incorporated by reference in this prospectus, and in any applicable prospectus supplement, before investing in these securities.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.

Delivery of the securities offered hereby is expected to be made on or about , 2026, subject to satisfaction of customary closing conditions.

E.F. Hutton & Co.

The date of this prospectus is , 2026

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