As filed with the Securities and Exchange Commission on December 8, 2025. Registration No. 333- UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM S-1 REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933 GRI BIO, INC. (Exact name of registrant as specified in its charter) (Primary Standard Industrial Classification Code Number) Delaware 2834 82-4369909 (I.R.S. Employer Identification Number) (State or other jurisdiction of incorporation or organization) 2223 Avenida de la Playa, ...