GRI Bio (NASDAQ: GRI) updates Form S-1 with extensive warrant and contract exhibits

Rhea-AI Filing Summary

GRI Bio, Inc., a Delaware-based biotechnology company headquartered in La Jolla, California, filed Amendment No. 1 to its Form S-1 registration statement. This amendment is described as an exhibits-only filing, meaning it primarily updates and compiles legal and contractual documents without changing the main disclosure sections. The exhibit list includes various forms of common stock purchase warrants, pre-funded warrants, Series F warrants, a form of securities purchase agreement, an updated engagement letter with H.C. Wainwright & Co., an equity incentive plan and related award agreements, key employment and consulting agreements, consents, and the filing fee table. The amendment is signed on behalf of the company by President and Chief Executive Officer W. Marc Hertz, Ph.D., and other directors and officers.

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

Registration No. 333-291999

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

Amendment No. 1 to

FORM S-1

REGISTRATION STATEMENT

UNDER

THE SECURITIES ACT OF 1933

GRI BIO, INC.

(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

La Jolla, CA 92037

(619) 400-1170

(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

GRI Bio, Inc.

2223 Avenida de la Playa, #208

La Jolla, CA 92037

(619) 400-1170

(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.

EXPLANATORY NOTE

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.

PART II

INFORMATION NOT REQUIRED IN PROSPECTUS

ITEM 16. EXHIBITS AND FINANCIAL STATEMENT SCHEDULES.

(1)Exhibits.

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

Incorporated by Reference

Exhibit No.

Description

Filed Herewith

Form

Date

File Number

5.1^

Opinion of Mintz, Levin, Cohn, Ferris, Glovsky and Popeo, P.C.

S-1

12/09/25

333-291999

10.1#

GRI Bio, Inc. Amended and Restated 2018 Equity Incentive Plan, as Amended.

8-K

08/13/25

001-40034

10.2#

Form of Nonqualified Stock Option Agreement under the Company’s Amended and Restated 2018 Equity Incentive Plan, as Amended.

S-1

10/23/20

333-249636

10.3#

Form of Incentive Stock Option Agreement under the Company’s Amended and Restated 2018 Equity Incentive Plan., as Amended

S-1

10/23/20

333-249636

10.4#

Form of Restricted Stock Unit Agreement under the Registrant’s Amended and Restated 2018 Equity Incentive Plan, as Amended.

S-8

08/13/25

333-289593

10.5#

GRI Bio Operations, Inc. 2015 Equity Incentive Plan.

S-4

12/23/22

333-268977

10.6△

Form of Securities Purchase Agreement.

8-K

05/13/22

001-40034

10.7△

Amendment No. 1 to Securities Purchase Agreement, by and between Vallon and each purchaser identified on the signature pages thereto, dated as of July 25, 2022.

8-K

07/26/22

001-40034

10.8#

Consulting and Clinical Advisory Board Agreement, by and between the Company and Rohit Loomba, M.D., dated as of June 3, 2016.

S-4

12/23/22

333-268977

10.9#

Consulting and Scientific Advisory Board Agreement, by and between the Company and Vipin Kumar Chaturvedi, personally or through Vidur Discoveries LLC, dated as of October 31, 2018.

S-4

12/23/22

333-268977

10.10△

Securities Purchase Agreement, by and between the Company and Altium Growth Fund, LP, dated as of December 13, 2022.

8-K

12/13/22

001-40034

10.11△

Securities Purchase Agreement, by and among the Company, Vallon and Altium Growth Fund, LP, dated as of December 13, 2022.

8-K

12/13/22

001-40034

10.12

Omnibus Amendment to Securities Purchase Agreements, by and among the Company, GRI Bio Operations, Inc., and Altium Growth Fund, LP, dated as of February 17, 2023.

S-4

03/06/23

333-268977

10.13△

Lease Agreement, by and between La Jolla Shores Plaza, LLC and GRI Bio Operations, Inc., dated as of March 2, 2018, for that property located at 2223 Avenida de la Playa, Suite 208, La Jolla, California, 92037, as amended on February 16, 2021 and February 20, 2024.

10-K

03/28/24

001-40034

10.14#

Amended and Restated Non-Employee Director Compensation Program.

10-Q

08/13/25

001-40034

10.15#

Form of Indemnification Agreement.

8-K

04/21/23

001-40034

10.16#

Employment Agreement, by and between GRI Bio Operations, Inc. and Marc Hertz, Ph.D., dated as of February 20, 2023.

S-4/A

02/24/23

333-268977

10.17#

Employment Agreement, by and between GRI Bio Operations, Inc. and Leanne M. Kelly, dated as of February 20, 2023.

S-4/A

02/24/23

333-268977

10.18#

Employment Agreement, by and between GRI Bio Operations, Inc. and Vipin Kumar Chaturvedi, dated as of February 20, 2023.

S-4/A

02/24/23

333-268977

Incorporated by Reference

Exhibit No.

Description

Filed Herewith

Form

Date

File Number

10.19#

Separation Agreement, by and between the Company and David Baker, dated as of April 21, 2023.

8-K

04/21/23

001-40034

10.20#

Employment Agreement, by and between the Company and Albert Agro, Ph.D., dated as of July 1, 2023.

10-Q

08/14/23

001-40034

10.21△

Asset Purchase Agreement, by and between the Company and Aardvark Therapeutics, Inc., dated as of August 22, 2023.

8-K

08/23/23

001-40034

10.22△

Form of Securities Purchase Agreement.

S-1/A

01/31/24

333-276025

10.23

Form of Placement Agent Agreement.

S-1/A

01/31/24

333-276025

10.24△

Form of Securities Purchase Agreement.

S-1/A

06/26/24

333-280323

10.25△

Form of Securities Purchase Agreement.

S-1

03/24/25

333-286072

10.26△^

Form of Securities Purchase Agreement.

S-1

12/09/25

333-291999

10.27

Form of Repricing Letter Agreement.

8-K

10/22/24

001-40034

10.28

At The Market Offering Agreement, dated May 20, 2024, by and between GRI Bio, Inc. and H.C. Wainwright & Co., LLC.

8-K

05/20/24

001-40034

10.29

Engagement Letter, dated October 21, 2024, by and between GRI Bio, Inc. and H.C. Wainwright & Co., LLC, as amended on December 5, 2025.

X

16.1

Letter from Sadler Gibb & Associates LLC, dated April 15, 2025.

8-K

04/15/25

001-40034

21.1

Subsidiaries.

S-1/A

12/04/23

333-274972

23.1^

Consent of Independent Registered Public Accounting Firm.

S-1

12/09/25

333-291999

23.2^

Consent of Mintz, Levin, Cohn, Ferris, Glovsky and Popeo, P.C. (included in Exhibit 5.1).

S-1

12/09/25

333-291999

24.1^

Powers of Attorney for directors and certain executive officers (contained on the signature page).

S-1

12/09/25

333-291999

107^

Filing Fee Table.

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.

^      Previously filed.

SIGNATURES

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

FAQ

What did GRI Bio, Inc. (GRI) file in this S-1/A amendment?

GRI Bio, Inc. filed Amendment No. 1 to its Form S-1 registration statement as an exhibits-only filing. The amendment updates the facing page, an explanatory note, the exhibit list, the signature page, and related exhibits, while leaving the rest of the registration statement unchanged.

What types of exhibits are included in GRI Bio, Inc.'s S-1/A Amendment No. 1?

The exhibit list includes warrant forms (such as Series C, D, E and F common warrants and pre-funded warrants), securities purchase agreements, a placement agent warrant, opinions and consents from legal counsel and auditors, an equity incentive plan and award agreements, key employment and consulting agreements, a lease agreement, and the filing fee table.

Which new or recent forms related to the current S-1 are highlighted in the exhibits for GRI Bio (GRI)?

Among the exhibits tied to the current registration, GRI Bio lists a Form of Placement Agent Warrant, a Form of Pre-Funded Warrant, a Form of Series F Warrant, a Form of Securities Purchase Agreement, a legal opinion from Mintz, Levin, Cohn, Ferris, Glovsky and Popeo, P.C., and consents associated with those documents.

Who signed GRI Bio, Inc.'s S-1/A Amendment No. 1 and in what capacities?

The amendment is signed on behalf of GRI Bio, Inc. by W. Marc Hertz, Ph.D., as President, Chief Executive Officer and Director. It is also signed by Chief Financial Officer Leanne Kelly as principal financial and accounting officer, and by directors including David Szekeres, David Baker, Roelof Rongen, and Camilla V. Simpson, M.Sc.

Where is GRI Bio, Inc. headquartered and how can the company be contacted?

GRI Bio, Inc. is headquartered at 2223 Avenida de la Playa, #208, La Jolla, CA 92037. The company lists a main telephone number of (619) 400-1170 for its principal executive offices and for contacting its President and Chief Executive Officer, W. Marc Hertz, Ph.D.

Which law firms are involved in GRI Bio, Inc.'s S-1/A amendment filing?

The amendment identifies Mintz, Levin, Cohn, Ferris, Glovsky and Popeo, P.C. in San Diego, California and Haynes and Boone, LLP in New York, New York as legal counsel, naming specific attorneys at each firm in connection with the registration statement.