As filed with the Securities and Exchange Commission on June 28, 2023 Registration No. 333-272752 UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Amendment No. 1 to FORM S-1 REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933 APTOSE BIOSCIENCES INC. (Exact Name of Registrant As Specified In Its Charter) | Canada | 2836 | 98-1136802 | | --- | --- | --- | | (State or other jurisdiction of incorporation or | (Primary Standard Industrial | (I.R.S. Employer | | organization) | Classif ...