Inhibrx Biosciences Inc

As filed with the Securities and Exchange Commission on June 11, 2024

Registration No. 333-

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORMS-1

REGISTRATION STATEMENT

UNDER

THE SECURITIES ACT OF 1933

(Exact name of registrant as specified in its charter)

11025 N. Torrey Pines Road, Suite 140

La Jolla, California 92037

(858) 795-4220

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

Mark Lappe

Chief Executive Officer

Inhibrx Biosciences, Inc.

11025 N. Torrey Pines Road, Suite 140

La Jolla, California 92037

(858) 795-4220

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

Copies to:

Jeremy Glaser

Melanie Ruthrauff Levy

Mintz, Levin, Cohn, Ferris,

Glovsky and Popeo, P.C.

3580 Carmel Mountain Road, Suite 300

San Diego, CA 92130

(858) 314-1500

Approximate date of commencement of proposed sale to the public:

As soon as practicable after the effective date of this registration statement.

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, please 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, or a smaller reporting company. See the definitions of “large accelerated filer,” “accelerated filer” and “smaller reporting 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 said Section 8(a), may determine.

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

SUBJECT TO COMPLETION, DATED June 11, 2024

2,449,921 shares of Common Stock

This prospectus relates to the proposed resale or other disposition from time to time of an aggregate of up to 2,449,921 shares of Inhibrx Biosciences, Inc., or the Company, common stock, $0.0001 par value per share, or Common Stock, including (i) 300,146 shares of Common Stock held by the selling stockholders who have registration rights pursuant to the Registration Rights Agreement, dated May 29, 2024, by and among the Company and the holders listed thereto, or the Registration Rights Agreement, (ii) 991,849 shares of Common Stock that are issuable upon the exercise of warrants to purchase shares of Common Stock at an exercise price of $0.0001 per share, subject to proportional adjustments in the event of stock splits or combinations or similar events, or the Warrants, held by the selling stockholders who have registration rights pursuant to the Registration Rights Agreement, and (iii) 1,157,926 shares of Common Stock currently held by Inhibrx, Inc., an indirect wholly-owned subsidiary of Sanofi S.A., or Sanofi. The shares of Common Stock and Warrants were issued in connection with the sale of Inhibrx, Inc.’s INBRX-101, which was completed on May 30, 2024, as described in this prospectus.

The Company is not selling any securities under this prospectus and will not receive any of the proceeds from the sale of securities by the selling stockholders, except that the Company may receive up to approximately $100 in aggregate gross proceeds from the exercise of the Warrants, if the Warrants are exercised for cash (and, as applicable, not on a cashless basis), based on the per share exercise price of the Warrants.

Our registration of the resale of the shares of Common Stock covered by this prospectus does not mean that the selling stockholders will offer or sell all or any of the shares of Common Stock. The selling stockholders or their assignees or successors-in-interest may offer and sell the shares of Common Stock described in this prospectus in a number of different ways and at varying prices. We provide more information about how a selling stockholders may sell its shares of Common Stock in the section entitled “Plan of Distribution” appearing elsewhere in this prospectus. We will pay the expenses incurred in registering the securities covered by the prospectus, including legal and accounting fees.

Our Common Stock is quoted on the Nasdaq Global Market under the symbol “INBX.” On June 7, 2024, the last reported sale price of our Common Stock was $16.65 per share.

We are an “emerging growth company” as that term is used in the Jumpstart Our Business Startups Act of 2012, and, as such, we have elected to comply with certain reduced public company reporting requirements for this prospectus and future filings with the Securities and Exchange Commission.

INVESTING IN OUR COMMON STOCK INVOLVES RISKS. SEE THE SECTION ENTITLED “RISK FACTORS” BEGINNING ON PAGE 10 OF THIS PROSPECTUS.

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.

The date of this prospectus is , 2024

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