Kura Oncology, Inc. announced that the U.S. Food and Drug Administration (FDA) has lifted the partial clinical hold on the KOMET-001 Phase 1b study of KO-539 in patients with relapsed or refractory acute myeloid leukemia (AML). The partial clinical hold was lifted following agreement with the FDA on the Company's mitigation strategy for differentiation syndrome, a known adverse event related to differentiating agents in the treatment of AML. About KOMET-001: KOMET-001 (Kura Oncology Menin Inhibitor Trial) is a Phase 1/2, first-in-human, open-label trial to determine the safety, tolerability and anti-tumor activity of KO-539 in patients with refractory or relapsed AML.

KO-539 demonstrated a wide therapeutic window in the Phase 1a dose-escalation portion of KOMET-001, with promising single-agent activity in an all-comer population of patients with relapsed or refractory AML, including patients with NPM1 mutations and KMT2A rearrangements. The Phase 1b portion includes two expansion cohorts – a lower dose of 200 mg and a higher dose of 600 mg. Kura expects to enroll 12 patients with NPM1-mutant or KMT2A-rearranged relapsed or refractory AML in each cohort and assess those patients for safety and tolerability, pharmacokinetics and efficacy to determine the recommended Phase 2 dose for KO-539.