Aptose Upgraded to Trade on OTCQB Market

Group 1 - Aptose Biosciences Inc. has been upgraded to trade on the OTCQB Market under the ticker symbol "APTOF" starting July 1, 2025, while continuing its listing on the Toronto Stock Exchange (TSX) under "APS" [1] - The OTCQB Venture Market is designed for early-stage and developing companies that are current in their reporting and undergo an annual verification process [2] - Aptose is a clinical-stage biotechnology company focused on developing precision medicines for oncology, particularly in hematology, with its lead product being the oral kinase inhibitor tuspetinib (TUS) [3]