FibroBiologics(FBLG) - Prospectus

As filed with the Securities and Exchange Commission on March 27, 2026. Registration No. 333- UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM S-1 REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933 FibroBiologics, Inc. (Exact name of registrant as specified in its charter) (State or other jurisdiction of incorporation or organization) Delaware 2834 86-3329066 (Primary Standard Industrial Classification Code Number) (I.R.S. Employer 455 E. Medical Center Blvd. Suite 300 Houst ...