Enasidenib and Azacitidine in Treating Patients With Recurrent or Refractory Acute Myeloid Leukemia and IDH2 Gene Mutation

PRIMARY OBJECTIVES: I. To determine the clinical activity of enasidenib mesylate (AG221, IDHIFA) in combination with azacitidine (AZA) for patients with relapsed/refractory acute myeloid leukemia is measured by overall response rate (ORR). SECONDARY OBJECTIVES: I. To determine duration of response, event-free survival (EFS), and overall survival (OS). II. To determine the safety of enasidenib in combination with azacitidine in patients with relapsed/refractory acute myeloid leukemia (AML). EXPLORATORY OBJECTIVES: I. To evaluate occurrence of minimal residual disease (MRD) negative status by IDH2 mutation analysis and flow cytometry. II. To investigate possible relationships between baseline protein and gene expression signatures and mutation profile and clinical response to the combination. III. To evaluate the incidence and characteristics of IDH-inhibitor related differentiation syndrome (IDH-DS) with combination therapy. OUTLINE: Patients receive azacitidine subcutaneously (SC) or intravenously (IV) over 30 minutes on days 1-7 and enasidenib mesylate orally (PO) once daily (QD) beginning on day 1. Cycles repeat every 4-6 weeks in the absence of disease progression or unacceptable toxicity. After completion of study treatment, patients are followed up at 30 days and then every 3-6 months for up to 5 years.