Eloxx Pharmaceuticals, Inc.

As filed with the Securities and Exchange Commission on September 11, 2026.

Registration No. 333-

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM

REGISTRATION STATEMENT

UNDER

THE SECURITIES ACT OF 1933

ELOXX PHARMACEUTICALS, INC.

(Exact name of registrant as specified in its charter)

P.O. Box 274

Arlington,

MA

,02476

Telephone:

(781)

577-5300

(Address, including zip code, and telephone number, including area code, of registrant’s principal executive offices)

Sumit Aggarwal

Chief Executive Officer

Eloxx Pharmaceuticals, Inc.

P.O. Box 274

Arlington,

MA

,02476

Telephone:

(781

)

577-5300

(Name, address, including zip code, and telephone number, including area code, of agent for service)

Copies to:

N. Danny Shulman

Michael Rosenberg

Philip D. Torrence

Honigman LLP

1440 New York Avenue, NW Suite 200

Washington, DC 20005

(202) 844 3380

Approximate date of commencement of proposed sale of the securities to the public: From time to time after this Registration Statement becomes effective.

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, a 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 Commission, acting pursuant to said 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 jurisdiction where the offer or sale is not permitted.

600,000 Shares of Common Stock

Up to 4,358,919 Shares of Common Stock Issuable upon Exercise of Pre-Funded Warrants

This prospectus relates to the resale from time to time, by the selling stockholders identified in this prospectus under the caption “Selling Stockholders,” of (i) 600,000 shares of our common stock, par value $0.01 (our “common stock”) and (ii) up to 4,358,919 shares of our common stock issuable upon the exercise ofpre-funded warrants (the“Pre-Funded Warrants”). We issued the Pre-Funded Warrants to the selling stockholders in a series of private placements pursuant to (i) the Securities Purchase Agreement, dated as of January 9, 2024 (the “Domicilium Securities Purchase Agreement”), and (ii) the Securities Purchase Agreement, dated as of August 20, 2025, as amended (the “Coastlands Securities Purchase Agreement”). The Pre-Funded Warrants have an exercise price of $0.11 per share, are exercisable at any time and will expire when exercised in full, subject to the beneficial ownership limitation.

The selling stockholders may, from time to time, sell, transfer or otherwise dispose of any or all of their common stock or interests in their common stock on any stock exchange, market or trading facility on which the common stock is traded or in private transactions. These dispositions may be at fixed prices, at prevailing market prices at the time of sale, at prices related to the prevailing market price, at varying prices determined at the time of sale, or at negotiated prices. See “Plan of Distribution” in this prospectus for more information. We will not receive any proceeds from the resale or other disposition of the shares of common stock by the selling stockholders. However, we will receive the proceeds of any cash exercise of the Pre-Funded Warrants. If all of the Pre-Funded Warrants are exercised for cash, we will receive aggregate proceeds of approximately $0.5 million. See “Use of Proceeds” beginning on page 58 and “Plan of Distribution” beginning on page 138 of this prospectus for more information.

Our common stock is listed on the Nasdaq Capital Market (“Nasdaq”) under the symbol “ELOX”. On September 10, 2026, the last reported sales price of our common stock on the Nasdaq was $16.28 per share.

We are a “smaller reporting company” as defined under the federal securities laws and, as such, have elected to comply with certain reduced reporting requirements for this prospectus and may elect to do so in future filings. See “Prospectus Summary-Implications of Being a Smaller Reporting Company.”

Investing in our common stock involves risks that are described in the “Risk Factors” section beginning on page 7 of this prospectus.

Neither the Securities and Exchange Commission nor any other regulatory body 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 , 2026.