SNDX-5613 and Gilteritinib for the Treatment of Relapsed or Refractory FLT3-Mutated Acute Myeloid Leukemia and Concurrent MLL-Rearrangement or NPM1 Mutation

This study is testing a combination of two drugs — SNDX-5613 and gilteritinib — in adults with relapsed or treatment-resistant AML (acute myeloid leukemia) that has specific genetic mutations (FLT3 mutation plus either an NPM1 mutation or MLL gene rearrangement). **You may be eligible if...** - You are 18 years old or older - You have been diagnosed with AML that has relapsed or stopped responding to treatment - Your leukemia has both a FLT3 mutation (ITD or TKD type) AND an NPM1 mutation or MLL gene rearrangement - You are considered too unwell for intensive chemotherapy - Your heart, liver, and kidney function are adequate - You are able to swallow oral medications **You may NOT be eligible if...** - You have acute promyelocytic leukemia (APL) - Your leukemia is only found outside the bone marrow (extramedullary) - You have a second active cancer requiring treatment - You are pregnant or breastfeeding - You have uncontrolled heart problems or a history of serious heart rhythm disorders - You have active hepatitis B, C, or HIV with detectable virus Talk to your doctor to see if this trial is right for you.