Kura Oncology Inc. (NASDAQ: KURA) and Kyowa Kirin Co. Ltd. (TSE: 4151) reported long-term results from their Phase 1/2 KOMET-007 trial testing ziftomenib combined with intensive chemotherapy in newly diagnosed acute myeloid leukemia patients.

The single-arm trial showed a 12-month overall survival rate of 94% among NPM1-mutant AML patients and 71% among KMT2A-rearranged AML patients. The companies reported 96% composite complete remission rates in NPM1-mutant AML patients and 90% in KMT2A-rearranged AML patients.

Median overall survival was not reached in either patient population, with median follow-up of 17.6 months for NPM1-mutant patients and 11.0 months for KMT2A-rearranged patients. The trial included 49 NPM1-mutant patients and 50 KMT2A-rearranged patients treated with 600 mg ziftomenib daily plus standard 7+3 chemotherapy.

The treatment showed high rates of measurable residual disease negativity, with 85% local negativity rates in NPM1-mutant AML and 82% in KMT2A-rearranged AML. Central testing showed 79% of NPM1-mutant responders achieved bone marrow MRD negativity at the 0.1% threshold.

Safety data showed ziftomenib was generally well tolerated with no new safety signals. Four patients experienced Grade 3 differentiation syndrome, and three patients had Grade 3 QTc prolongation events. The 60-day mortality rate was 2% in NPM1-mutant patients.

Ziftomenib received FDA approval in May 2024 as monotherapy for relapsed or refractory NPM1-mutated AML patients. The companies are conducting the Phase 3 KOMET-017 registrational trial testing the combination in newly diagnosed patients.

The results will be presented at the European Hematology Association 2026 Congress, according to the companies' statement.