The safety, tolerability, and antileukemic response of ziftomenib in combination with standard of care treatments for patients with relapsed/refractory acute myeloid leukemia will be examined with the following agents: FLAG-IDA, low-dose cytarabine, and gilteritinib.

Key Inclusion Criteria:

• Has been diagnosed with relapsed/refractory AML.
• Has a documented NPM1 mutation or KMT2A rearrangement.
• Has a documented FLT3 mutation (cA-3 only).
• Has an Eastern Cooperative Oncology Group (ECOG) Performance status ≤ 2.
• Has adequate hepatic and renal function as defined per protocol.
• Has an ejection fraction above a protocol defined limit.
• Participant, or legally authorized representative, must be able to understand and provide written informed consent prior to the first screening procedure.
• Has agreed to use contraception as defined per protocol.

Key Exclusion Criteria:

• Has a diagnosis of acute promyelocytic leukemia or blast chronic myeloid leukemia.
• Has clinically active central nervous system leukemia.
• Has an active and uncontrolled infection.
• Has a mean corrected QT interval (QTcF) > 480ms.
• Has uncontrolled intercurrent illness, including, but not limited to protocol defined cardiac disease.
• Has received radiation, chemotherapy, immunotherapy, or any other anticancer therapy including investigational therapy <14 days or within 5 drug half-lives prior to the first dose of study intervention.
• Has had major surgery within 4 weeks prior to the first dose of study intervention.
• Has received a hematopoietic stem cell transplant (HSCT) and has not previously had adequate recovery per protocol defined criteria.
• Has active graft-versus-host disease (GvHD) and or on immunosuppressive drugs for the treatment of GvHD
• Participant is pregnant or lactating.