Hanmi Pharmaceutical said on Monday that its U.S. partner, Aptose Bioscience, confirmed complete remission in phase 1/2 clinical trials of HM43239, an acute myeloid leukemia (AML) treatment (ingredient: tuspetinib), in all three doses (80 mg, 120 mg, and 160 mg). The trials took place in the U.S. and Korea.

Aptose Bioscience confirmed cases of complete response (CR) subsequently in various mutant patients who received Hanmi Pharmaceutical's new drug for the treatment of AML using HM43239.

The results were also presented in a webinar on Nov. 3 held for key opinion leaders and the United States Adopted Name (USAN) decided that tuspetinib was the ingredient name for HM43239 at this meeting, Hanmi said.

Accordingly, Aptose Bioscience will present the details of the study at the 64th American Society of Hematology (ASH) in Los Angeles, the U.S., from Dec.10-13.

HM43239 is a once-daily oral myeloid kinome inhibitor (MKI) targeting key kinases acting in myeloid malignancies, and has been designated as a fast-track development drug in May 2021 and an orphan drug by the U.S. FDA in 2018.

Based on the successful results of this trial, Aptose Bioscience also plans to expand single-dose and combination therapy trials in the future. In the single-dose therapy expansion trial, they will start with the efficacy of HM43239 120 mg in patients with AML, including patients with FLT3 - a receptor important for the normal development of hematopoietic stem cells and progenitor cells - mutations who do not respond to conventional FLT3 inhibitors.

Additionally, the company plans to conduct a combination clinical trial of HM43239 80 mg with the existing AML treatment Venclexta (ingredient: venetoclax).