Inclusion Criteria:

- A histologically or pathologically confirmed diagnosis of AML based on WHO
classification which is previously untreated by systemic therapy or is in first
relapse after achieving a complete remission to initial induction, consolidation
and/or maintenance therapy or MDS with IPSS scores of intermediate -2 or higher risk
risk which has been previously treated with hypomethylating agents

- Age 70 years or older for AML and 60 years or older for MDS

- Eastern Cooperative Oncology Group (ECOG) performance status 0-2

- Adequate renal function defined as serum creatinine equal to or less than 1.5 x upper
limit of normal (ULN)

- Adequate liver function defined as total bilirubin or direct bilirubin equal to or
less than 1.5 x ULN; alanine aminotransferase (ALT or SGPT) equal to or less than 2.5
x ULN (5 x ULN if tumor has affected the liver)

- Life expectancy reasonably adequate for evaluating the treatment effect

- Patient must be able to swallow capsules

- Patients must be at least 2 weeks from prior systemic therapy, radiation therapy,
major surgery, or other investigational therapy, and have recovered from clinically
significant toxicities of these prior treatments

- All men and women of reproductive potential must agree to practice effective
contraception for 4 weeks prior to study entry, during the entire study period and
for one month after the study unless documentation of infertility exists

- Ability to understand and willingness to sign the informed consent form

Exclusion Criteria:

- AML is of the sub-type of acute promyelocytic leukemia

- Having received more than one induction systemic therapy for AML or having received a
standard dose or high dose ara-C containing regimen for MDS

- Patients with known central nervous system (CNS) involvement by leukemia

- Uncontrolled intercurrent illness including, but not limited to ongoing or active
infection, active cancer(s) other than AML, symptomatic congestive heart failure,
unstable angina pectoris, cardiac arrhythmia, or psychiatric illness/social
situations that would limit compliance with study requirements. Patients receiving
intravenous antibiotics for infections that are under control may be included in this
study

- Known to be HIV-positive