Document

As filed with the Securities and Exchange Commission on December 9, 2025.

Registration No. 333-291999

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

REGISTRATION STATEMENT

THE SECURITIES ACT OF 1933

(Exact name of registrant as specified in its charter)


Delaware	2834	82-4369909
(State or other jurisdiction of incorporation or organization)	(Primary Standard Industrial Classification Code Number)	(I.R.S. Employer Identification Number)

2223 Avenida de la Playa, #208

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

W. Marc Hertz, Ph.D.

President and Chief Executive Officer

2223 Avenida de la Playa, #208

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


Copies to:
Adam Lenain, Esq. Melanie Ruthrauff Levy, Esq. Mintz, Levin, Cohn, Ferris, Glovsky and Popeo, P.C. 3580 Carmel Mountain Road, Suite 300 San Diego, California 92130 Tel: (858) 314-1500			Rick A. Werner, Esq. Alla Digilova, Esq. Haynes and Boone, LLP 30 Rockefeller Plaza, 26th Floor New York, New York 10112 (212) 659-7300

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, 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.

Large accelerated filer

☐

Accelerated filer

☐

Non-accelerated filer

☒

Smaller reporting company

☒

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 7(a)(2)(B) of the Securities Act. o

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 or until this Registration Statement shall become effective on such date as the Securities and Exchange Commission, acting pursuant to said Section 8(a), may determine.

GRI Bio, Inc. is filing this Amendment No. 1 to its Registration Statement on Form S-1 (File No. 333-291999) as an exhibits-only filing. Accordingly, this amendment consists only of the facing page, this explanatory note, Item 16(a) of Part II of the Registration Statement, the signature page to the Registration Statement and the filed exhibits. The remainder of the Registration Statement is unchanged and has been omitted.

INFORMATION NOT REQUIRED IN PROSPECTUS

ITEM 16. EXHIBITS AND FINANCIAL STATEMENT SCHEDULES.

Incorporated by Reference

Exhibit No.

Description

Filed Herewith

Form

Date

File Number

2.1△

Agreement and Plan of Merger, by and among the Company, Vallon, and Vallon Merger Sub, Inc., dated as of December 13, 2022.

8-K

12/13/22

001-40034

2.2

Amendment to Agreement and Plan of Merger, by and among the Company, Vallon, and Vallon Merger Sub, Inc., dated as of February 17, 2023.

S-4/A

02/24/23

333-268977

3.1

Amended and Restated Certificate of Incorporation, as amended.

10-K

03/14/25

001-40034

3.2

Amended and Restated Bylaws.

8-K/A

05/26/23

001-40034

4.1

Specimen Common Stock Certificate.

S-1

10/23/20

333-249636

4.2

Form of Common Stock Purchase Warrant.

8-K

5/13/22

001-40034

4.3

Form of Amendment No. 1 to Common Stock Purchase Warrant.

8-K

07/26/22

001-40034

4.4

Form of Equity Warrant.

8-K

12/13/22

001-40034

4.5

Form of Exchange Warrant.

8-K

12/13/22

001-40034

4.6

Form of Senior Secured Note of GRI Bio Operations, Inc.

S-4

12/23/22

333-268977

4.7

Warrant to Purchase Stock issued to TEP Biotech, LLC, dated as of November 2, 2018.

S-4

12/23/22

333-268977

4.8

Warrant to Purchase Stock issued to TEP Biotech, LLC, dated as of December 3, 2019.

S-4

12/23/22

333-268977

4.9

Warrant to Purchase Stock issued to TEP Biotech, LLC, dated as of July 7, 2022.

S-4

12/23/22

333-268977

4.10

Warrant to Purchase Stock issued to Oppel Greeff, dated as of July 7, 2022.

S-4

12/23/22

333-268977

4.11

Form of Amendment to 2022 Warrant to Purchase Stock.

S-4/A

01/30/23

333-268977

4.12

Form of Series B-1 Common Warrant.

S-1/A

01/31/24

333-276025

4.13

Form of Series B-2 Common Warrant.

S-1/A

01/31/24

333-276025

4.14

Form of Placement Agent Warrant.

S-1/A

06/26/24

333-280323

4.15

Form of Series C-1 Common Warrant.

S-1/A

06/26/24

333-280323

4.16

Form of Series C-2 Common Warrant.

S-1/A

06/26/24

333-280323

4.17

Form of Placement Agent Warrant.

8-K

10/22/24

001-40034

4.18

Form of Series D-1 Common Warrant.

8-K

10/22/24

001-40034

4.19

Form of Series D-2 Common Warrant.

8-K

10/22/24

001-40034

4.20

Form of Placement Agent Warrant.

S-1

03/24/25

333-286072

4.21

Form of Pre-Funded Warrant.

S-1

03/24/25

333-286072

4.22

Form of Series E Warrant.

S-1

03/24/25

333-286072

4.23^

Form of Placement Agent Warrant.

S-1

12/09/25

333-291999

4.24^

Form of Pre-Funded Warrant.

S-1

12/09/25

333-291999

4.25^

Form of Series F Warrant.

S-1

12/09/25

333-291999

Unless otherwise indicated, exhibits are filed herewith.

△ Schedules and exhibits have been omitted pursuant to Item 601(a)(5) of Regulation S-K. The Company undertakes to furnish supplemental copies of any of the omitted schedules upon request by the U.S. Securities and Exchange Commission.

# Indicates a management contract or any compensatory plan, contract or arrangement.

Pursuant to the requirements of the Securities Act of 1933, as amended, the registrant has duly caused this registration statement to be signed on its behalf by the undersigned, thereunto duly authorized, in La Jolla, California, on this 9th day of December, 2025.


GRI BIO, INC.

By:			/s/ W. Marc Hertz, Ph.D.
			W. Marc Hertz, Ph.D.
			President and Chief Executive Officer

Pursuant to the requirements of the Securities Act of 1933, as amended, this registration statement has been signed by the following persons in the capacities and on the dates indicated.

Signature

Title

Date

/s/ W. Marc Hertz, Ph.D.

President, Chief Executive Officer and Director

December 9, 2025

W. Marc Hertz, Ph.D.

(Principal Executive Officer)

Chief Financial Officer

December 9, 2025

Leanne Kelly

(Principal Financial and Accounting Officer)

Director and Chairperson of the Board

December 9, 2025

David Szekeres

Director

December 9, 2025

David Baker

Director

December 9, 2025

Roelof Rongen

Director

December 9, 2025

Camilla V. Simpson, M.Sc.


*By:			/s/ W. Marc Hertz, Ph.D.
			W. Marc Hertz, Ph.D.
			Attorney-in-fact