Aptose’s tuspetinib clinical data featured in oral presentation at 2023 ASH

Aptose Biosciences announced that a growing body of clinical data for Aptose’s lead compound tuspetinib, demonstrates significant benefit as a single agent and in combination with venetoclax in patients with relapsed or refractory acute myeloid leukemia in the ongoing APTIVATE Phase 1/2 study. As a single agent at therapeutic doses of 80-160 mg in 68 evaluable patients, TUS was more active in VEN-naive patients, with an overall CRc rate of 29%. This included a 42% CRc rate in FLT3-mutated patients and a 19% CRc rate in FLT3-unmutated, or wildtype, AML patients. Responses and blood counts improved with continuous dosing. Many bridged to an allogeneic stem cell transplant. Durability was observed when HSCT was not performed. 80 mg was selected as the recommended phase 2 dose. Tuspetinib showed a favorable safety profile with only mild adverse events and no dose-limiting toxicities up to 160 mg per day, and no drug discontinuations from drug related toxicity, In the TUS/VEN doublet study, 49 patients were dosed with 80 mg of tuspetinib and 200 mg of venetoclax, with 36 evaluable. Patients were heavily exposed to Prior-VEN and Prior-FLT3 inhibitor treatment. TUS/VEN was active in both VEN-naive and prior Prior-VEN relapsed/refractory patients.