Registration No. 333- UNITED STATES SECURITIES AND EXCHANGE COMMISSION Table of Contents As filed with the Securities and Exchange Commission on April 10, 2026 WASHINGTON, D.C. 20549 FORM S-1 REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933 HEMAB THERAPEUTICS HOLDINGS, INC. (Exact name of registrant as specified in its charter) Delaware 2836 41-4241952 (State or other jurisdiction of incorporation or organization) (Primary Standard Industrial Classification Code Number) (I.R.S. Employer Identificatio ...