As filed with the Securities and Exchange Commission on December 4, 2023. Registration No. 333-274972 UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 PRE-EFFECTIVE AMENDMENT NO. 1 TO FORM S-3 ON FORM S-1 REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933 GRI BIO, INC. (Exact name of registrant as specified in its charter) (State or other jurisdiction of incorporation or organization) (Primary Standard Industrial Classification Code Number) Delaware 2834 82-4369909 (I.R.S. Employ ...