A Phase 1 Study of BMF-500 in Adults With Acute Leukemia

Key Inclusion Criteria: * Age ≥ 18 years. * Individuals with histologically or pathologically confirmed diagnosis of relapsed or refractory AML with documented FLT3 mutation, and/or Individuals with histologically or pathologically confirmed diagnosis of their malignancy with wild-type FLT3 (including those with MLL1-R and NPM1 mutations). * ECOG performance status of 0-2. * Adequate liver and renal function * Adhere to the CYP3A4 inhibitor concomitant therapy use requirements, as follows: * Arm A: Participants must not have received a moderate or strong CYP3A4 inhibitor for at least 7 days prior to enrollment and are not anticipated to require such agents in the near term (for at least 4 weeks). * Arm B: Participants must have received a necessary azole antifungal(s) that is a strong CYP3A4 inhibitor (excluding other strong CYP3A4 inhibitor\[s\]) for at least 7 days prior to enrollment and be able to continue such azole antifungal(s) while on BMF-500 treatment for at least 4 weeks. * Arm C: Participants must have received necessary azole antifungal(s) that are moderate CYP3A4 inhibitors (excluding other moderate CYP3A4 inhibitors) for at least 7 days prior to enrollment and be able to continue such azole antifungal(s) while on BMF-500 treatment for at least 4 weeks (Cycle 1). Key Exclusion Criteria: * Significant cardiovascular disease including unstable angina pectoris, uncontrolled hypertension or arrhythmia, history of cerebrovascular accident including transient ischemic attack within 6 months prior to the first dose of the trial intervention. * WBC count \>50,000/µL (uncontrollable with cytoreductive therapy). * Women who are pregnant or lactating or plan to become pregnant.