FibroBiologics(FBLG) - Prospectus

As filed with the Securities and Exchange Commission on December 23, 2025. Registration No. 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) (I.R.S. Employer Identification Number) 455 E. Medical Center Blvd. Suite 300 Houston, Texas 77598 (281) 671-5150 Delaware 2834 86-3329066 (Prim ...