Inclusion Criteria:

          -  Documented informed consent of the participant and/or legally authorized
             representative

          -  Agreement to allow the use of archival tissue from diagnostic tumor biopsies

               -  If unavailable, exceptions may be granted with study principal investigator (PI)
                  approval

          -  Eastern Cooperative Oncology Group (ECOG) =< 2 or Karnofsky performance status (KPS)
             >= 70

          -  Recipients of allogeneic HCT - all stem cell sources including sibling, unrelated,
             mismatched related/unrelated, cord and haploidentical transplant patients will be
             included

          -  Conditioning regimen: Investigator's choice based on center guidelines

          -  GvHD prophylaxis: sirolimus + tacrolimus or tacrolimus + methotrexate or investigator
             choice

          -  Patients must have acute myeloid leukemia (AML) with IDH2 mutation at diagnosis. Day
             30 marrow post HCT should show evidence of morphologic remission with < 5% bone marrow
             blasts. Patients with MRD either by flow cytometry or IDH2 mutation testing will be
             allowed

          -  Patients with previous therapy with IDH2 inhibitors will be included

          -  Absolute neutrophil count (ANC) > 1000 (performed within 28 days prior to day 1 of
             protocol therapy unless otherwise stated)

          -  Hemoglobin >= 9.5 gm% (performed within 28 days prior to day 1 of protocol therapy
             unless otherwise stated)

          -  Platelets > 50,000/mm^3 (performed within 28 days prior to day 1 of protocol therapy
             unless otherwise stated)

          -  Platelets >= 20,000/mm^3 (performed within 28 days prior to day 1 of protocol therapy
             unless otherwise stated)

               -  NOTE: Patients with lower counts can enroll if infection cytomegalovirus
                  (CMV)/human herpesvirus 6 (HHV6) etc. is being treated actively

          -  Total bilirubin =< 1.5 X upper limit of normal (ULN) (unless has Gilbert's disease)
             (performed within 28 days prior to day 1 of protocol therapy unless otherwise stated)

          -  Total bilirubin < 2.0 mg/dl-exception permitted in patients with Gilbert's Syndrome
             (performed within 28 days prior to day 1 of protocol therapy unless otherwise stated)

          -  Aspartate aminotransferases (AST) (serum glutamic-oxaloacetic transaminase
             [SGOT])/alanine aminotransferase (ALT) (serum glutamate pyruvate transaminase [SGPT])
             =< 2 x ULN, patients with abnormal liver function tests (LFTs) in the context of
             active GVHD will not be included (performed within 28 days prior to day 1 of protocol
             therapy unless otherwise stated)

          -  Creatinine clearance of >= 40/min/1.73 m^2 for participants with creatinine levels
             above institutional normal per 24 hour urine test or the Cockcroft-Gault formula
             (performed within 28 days prior to day 1 of protocol therapy unless otherwise stated)

          -  Corrected QT (QTc) =< 480 ms

               -  Note: To be performed within 28 days prior to day 1 of protocol therapy

          -  Seronegative for human immunodeficiency virus (HIV) antigen/antibody (Ag/Ab) combo,
             hepatitis C virus (HCV), active hepatitis B virus (HBV) (surface antigen negative),
             and syphilis (rapid plasma reagin [RPR])

               -  If positive, hepatitis C ribonucleic acid (RNA) quantitation must be performed

          -  Women of childbearing potential (WOCBP): negative urine or serum pregnancy test

               -  If the urine test is positive or cannot be confirmed as negative, a serum
                  pregnancy test will be required

          -  Agreement by females and males of childbearing potential to use an effective method of
             birth control or abstain from heterosexual activity for the course of the study
             through at least 3 months after the last dose of protocol therapy

               -  Childbearing potential defined as not being surgically sterilized (men and women)
                  or have not been free from menses for > 1 year (women only)

        Exclusion Criteria:

          -  History of allergic reactions attributed to compounds of similar chemical or biologic
             composition to study agent

          -  Active diarrhea considered clinically significant and may impair oral drug
             administration

          -  Clinically significant uncontrolled illness

          -  Active infection requiring antibiotics

               -  Active infection. Patients with treated viral, bacterial or fungal infections
                  that are controlled on therapy will be allowed to participate

          -  Known history of immunodeficiency virus (HIV) or hepatitis B or hepatitis C infection

          -  Diagnosis of Gilbert's disease

          -  Other active malignancy. Participants with history of prior malignancy treated with
             curative intent who achieved complete response (CR) more than 2 years before study
             entry are eligible. This exclusion rule does not apply to non-melanoma skin tumors and
             in-situ cervical cancer

          -  Females only: Pregnant or breastfeeding

          -  Active grade II-IV acute GVHD and/or requiring systemic steroids with prednisone dose
             equivalent of >= 0.25 mg/kg at end of 4 weeks

          -  Any other condition that would, in the investigator's judgment, contraindicate the
             patient's participation in the clinical study due to safety concerns with clinical
             study procedures

          -  Prospective participants, who, in the opinion of the investigator, may not be able to
             comply with all study procedures (including compliance issues related to
             feasibility/logistics)