INCLUSION CRITERIA

          -  Elderly patients with FLT3-mutated acute myeloid leukemia (AML)

          -  Prior enrollment in Stanford study IRB-25737

          -  In continued complete remission

          -  ≥ 30 days but ≤ 90 days post allogeneic hematopoietic cell transplant (HCT); treatment
             on this study protocol must begin before day 90 post-HCT

          -  Absolute neutrophil count (ANC) ≥ 1000 cells/uL

          -  Hemoglobin ≥ 8.0 g/dL and not requiring regular transfusions

          -  Platelets ≥ 50,000 cells/uL and not requiring regular transfusions

          -  Aspartate aminotransferase (AST) ≤ 2.5 times upper limit of normal (ULN)

          -  Alanine aminotransferase (ALT) ≤ 2.5 X ULN

          -  Serum bilirubin ≤ 2.5 times ULN

          -  Ability to give written informed consent, including via legally authorized
             representative

          -  Corrected QT (QTc) ≤ 450 msec

          -  Ejection fraction (EF) ≥ 45% by 2-dimensional transthoracic echocardiography (TTE) or
             multiple-gated acquisition (MUGA)

          -  Sexually active males, including vasectomized males, must agree via informed consent
             to use a condom during vaginal, anal, or oral intercourse, while taking midostaurin
             and for 5 months after stopping midostaurin

          -  Females must have or be:

               -  Negative pregnancy test, within 21 days of the first dose of midostaurin OR

               -  Not of childbearing potential as follows:

                    -  Has undergone a hysterectomy or bilateral oophorectomy;

                    -  Has not had menses at any time in the preceding 24 consecutive months

        EXCLUSION CRITERIA

          -  Uncontrolled acute graft-vs-host disease (GVHD) grade 3 to 4

          -  Uncontrolled active infection

          -  Evidence of active AML (eg, circulating peripheral blasts on complete blood count)

          -  Known confirmed diagnosis of human immunodeficiency virus (HIV) infection

          -  Known confirmed diagnosis of active viral hepatitis

          -  QTc > 450 msec

          -  Congenital long QT syndrome

          -  History of presence of sustained ventricular tachycardia, history of ventricular
             fibrillation or torsades de pointes

          -  Bradycardia defined as heart rate (HR) < 50 beats per minute (bpm)

          -  Bifascicular block (right bundle branch block plus left anterior hemiblock)

          -  Congestive heart failure (CHF) New York Heart Association (NYHA) class 3 or 4

          -  Cardiac ejection fraction (EF) < 45% within 28 days prior to starting cycle 1

          -  Other known malignancy (except carcinoma in situ)

          -  Other concurrent severe and/or uncontrolled medical condition which could compromise
             participation in the study, eg:

               -  Uncontrolled diabetes

               -  Chronic active pancreatitis

               -  Myocardial infarction within 6 months

               -  Poorly-controlled hypertension

               -  Chronic kidney disease

          -  Received any investigational agent within 30 days prior to day 1

          -  Antineoplastic chemotherapy or radiotherapy within 28 days prior to cycle 1

          -  No plans for concurrent chemotherapy while on study (exception: antineoplastic drugs
             used as part of GVHD prophylaxis or treatment)

          -  Any surgical procedure, excluding central venous catheter placement, bone marrow
             biopsy or other minor procedures (eg, skin biopsy) within 14 days of day 1

          -  Unwillingness or inability to comply with the protocol

          -  Known malignant disease of the central nervous system

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

          -  Concomitant use of strong inhibitors of cytochrome P450 family 3 subfamily A member 4
             (CYP3A4)

          -  Pregnant or lactating

          -  Women of child-bearing potential