Inclusion Criteria:

          1. Confirmed diagnosis of refractory/relapsed AML or high-risk MDS

               -  Arm 1: Subjects must have received at least one prior therapy and a maximum of
                  three prior therapies

               -  Arm 2: Subjects must have received at least one prior therapy and a maximum of
                  three prior therapies. No prior treatment with 5-Azacitidine is allowed in this
                  arm.

          2. FLT3 mutation positive (ITD, TKD or other)

          3. ECOG PS 0-2

          4. Adequate liver and renal function

          5. Negative pregnancy test

          6. Extramedullary leukemia allowed except CNS disease

        Exclusion Criteria:

          -  Arm 1 and 2 Exclusion:

               1. <5% blasts in marrow or blood at time of screening

               2. Active HIV, hepatitis B or C

               3. CNS leukemia

               4. Clinically significant GVHD or organ dysfunction where chemotherapy specified by
                  protocol cannot be given

               5. Patient with AML-M3 (APL)

               6. Pre-existing liver diseases (i.e. cirrhosis, chronic hepatitis B or C,
                  nonalcoholic steatohepatitis, sclerosing cholangitis)