Announcement • Dec 06
Aptose Biosciences Inc.'s Tuspetinib Triple Drug Therapy Featured At the 2025 ASH Annual Meeting Aptose Biosciences Inc. featured clinical data for its lead compound tuspetinib (TUS) combined with standard dosing of venetoclax (VEN) and azacitidine (AZA) in a poster presentation at the 67thAmerican Society of Hematology (ASH) Annual Meeting in Orlando, FL. Updated data from patients in the TUSCANY trial across all three cohorts, 40 mg, 80 mg or 120 mg TUS dose in TUS+VEN+AZA, reveal promising clinical safety and antileukemic activity and support the use of TUS in combination with standard of care treatment across a broad range of AML populations, including those with adverse mutations regardless of FLT3 mutation status. Key Findings and Messages: In newly diagnosed AML patients, TUS+VEN+AZ A shows promising safety, tolerability and resilient efficacy, including MRD-negative remissions across a broad mutational spectrum. High-quality clinical responses (CR/CRh): 90% across 40, 80 and 120 mg dose levels; 100% at the higher 80 mg and 120 mg dose levels; Observed in FLT3-WT, FLT3-ITD, and NPM1c genetic subgroups; Observed in biallelic TP53/complex karyotype and RAS adverse genetic subgroups; Observed In AML with MDS-related mutations; MRD negativity: 78% by central flow cytometry in responding subjects; TUS targets VEN resistance mechanisms; inhibits kinase-driven abnormal signaling; Two subjects transitioned to stem cell transplantation and both returned for TUS maintenance; TUS+VEN+AZ a triplet therapy was well tolerated with no dose-limiting toxicities (DLTs) across all evaluable TUS dose levels; No DLTs including no prolonged myelosuppression for subjects in remission in Cycle 1; No drug-related deaths, differentiation syndrome, QTc prolongation, or CPK elevation reported; 8/10 evaluable subjects experienced red cell and platelet transfusion independence for > 8 weeks after their best response; Febrile neutropenia was reported in 2 subjects (16.7%), with 1 subject related to TUS; At the recently enrolled 160 mg dose level, preliminary findings show patients achieving early blast clearance with MRD-negativity and formal responses in the first few weeks of treatment (not included in poster data cut). Announcement • Nov 19
Hanmi Pharm. Co., Ltd. (KOSE:A128940) entered into a definitive arrangement agreement to acquire remaining 80.07% stake in Aptose Biosciences Inc. (TSX:APS) for CAD 4.9 million. Hanmi Pharm. Co., Ltd. (KOSE:A128940) entered into a definitive arrangement agreement to acquire remaining 80.07% stake in Aptose Biosciences Inc. (TSX:APS) for CAD 4.9 million on November 19, 2025. Under the terms of the Arrangement Agreement, upon the completion of the transactions contemplated under the Arrangement Agreement, Aptose shareholders, other than the Hanmi Purchasers and their respective affiliates that hold any Common Shares, will receive CAD 2.41 in cash per Common Share, which represents a premium of 28% over Aptose’s 30-day VWAP of C$1.88 on the Toronto Stock Exchange (TSX). Upon completion, Hanmi Pharm. Co., Ltd. will own 100% stake in Aptose Biosciences Inc. In case of termination of transaction, seller will pay a termination fee of CAD 0.30 million.
The transaction is subject to approval of merger agreement by target board, approval of offer by target shareholders and subject to court approval. The Board of Directors of Aptose Biosciences Inc. formed a special committee for the transaction. The deal has been unanimously approved by the board. The expected completion of the transaction is January 16, 2026.
Locust Walk Partners, LLC acted as fairness opinion provider and financial advisor for Aptose Biosciences Inc. and the Special Committee. McCarthy Tétrault LLP acted as legal advisor for Aptose Biosciences Inc. Stikeman Elliott LLP acted as legal advisor for Hanmi Pharm. Co., Ltd. Announcement • Oct 16
Aptose's Tuspetinib Exceeds Expectations When Combined with Standard of Care Treatment Across Diverse Populations of Newly Diagnosed AML Aptose Biosciences Inc. announced that data from the ongoing TUSCANY trial of tuspetinib in combination with venetoclax and azacitidine (TUS+VEN+AZA) are being presented in a poster presentation, "TUSCANY Study of Safety and Efficacy of Tuspetinib plus Standard of Care Venetoclax and azacITidine in Study Participants with Newly Diagnosed AML Ineligible for Induction Chemotherapy," at the European School of Haematology (ESH) 7th International Conference on Acute Myeloid Leukemia "Molecular and Translational" Advances in Biology and Treatment, being held from October 16-18, 2025 in Estoril, Portugal. Data to date from 10 patients in the TUSCANY trial across all three cohorts, 40 mg, 80 mg or 120 mg TUS dose in TUS+VEN+AZA, reveal promising clinical safety and antileukemic activity and support the use of TUS with standard of care treatment across a broad range of AML populations, including those carrying adverse mutations regardless of FLT3 mutation status. The TUS+ven+AZA triplet is being developed as a safe and well-tolerated, mutation agnostic frontline therapy to treat large, mutationally diverse populations of newly diagnosed AML patients who are ineligible to receive induction chemotherapy. Across all dose cohorts to date, no significant safety concerns or dose limiting toxicities (DLTs) have been observed in the TUSCANY trials, including no prolonged myelosuppression in Cycle 1 of subjects in remission, no reports of drug-related QTc prolongation or differentiation syndrome (DS), no CPK elevated and no treatment-related deaths. Dosing has begun at the 160 mg TUS dose level. 
