A Study of Revumenib in Combination With Chemotherapy in Participants With R/R Acute Leukemia

Key Inclusion Criteria: * Participants must have documented relapsed or refractory (R/R) AML, ALL, or acute leukemias of ambiguous lineage (ALAL) including MPAL and acute undifferentiated leukemia (AUL) harboring KMT2A rearrangement, KMT2A amplification, NPM1c, or NUP98r. * White blood count must be \<25,000/microliter prior to the first dose of revumenib. Participants may receive cytoreduction per protocol prior to beginning revumenib. * Eastern Cooperative Oncology Group performance status score 0-2 (if aged ≥18 years); Karnofsky Performance Scale of ≥50 (if aged ≥16 years and \<18 years); Lansky Performance Score of ≥50 (if aged \<16 years). * Adequate liver, kidney, and cardiac function * Participant must be taking 1 of the following medications for antifungal prophylaxis: itraconazole, ketoconazole, posaconazole, or voriconazole. * A female of childbearing potential must agree to use a highly effective method of contraception or double barrier method from the time of enrollment through 120 days following the last study drug dose. * A male of childbearing potential must agree to use barrier contraception from the time of enrollment through 120 days following the last study drug dose. Key Exclusion Criteria: * Any unresolved ≥Grade 2 reversible toxicity from previous anticancer therapy except alopecia or Grade 2 neuropathy * Graft-Versus-Host Disease (GVHD): Signs or symptoms of acute or chronic GVHD \>Grade 0 within 4 weeks of enrollment. All transplant participants…