Inclusion Criteria:

- Able to provide written informed consent, and be willing and able to comply with all
the study procedures

- Must be 60 years of age or older

- Must have a pathologic confirmation of newly diagnosed (de novo or untreated
secondary) AML or newly diagnosed Int-2 or high-risk MDS (IPSS classification)
according to WHO criteria

- Must have a Eastern Cooperative Oncology Group (ECOG) performance status of 0, 1, or
2

- Must have adequate organ function, including total bilirubin ≤ 1.5 x upper limit of
normal (ULN); AST & ALT ≤ 2.5 x ULN; and serum creatinine ≤ 2.0 x ULN.

Exclusion Criteria:

- Considered fit for intensive chemotherapy and opt to be treated with intensive
chemotherapy

- Prior transplantation or any prior anticancer therapy (standard or investigational,
including chemotherapy, treatment with HDAC inhibitors, or combination HDAC and
azacitidine) administered to treat AML or MDS.

- Clinical evidence of central nervous system (CNS) involvement by leukemia

- A diagnosis of promyelocytic leukemia

- Previous or concurrent malignancy except adequately treated basal cell or squamous
cell skin cancer; in situ carcinoma of the cervix, or other solid tumor treated
curatively, and without evidence of recurrence for at least 3 years prior to study
entry

- Active and uncontrolled clinically significant infection

- Known positive serology for hepatitis B surface antigen (HBsAg), hepatitis C antibody
(HCV Ab) or human immunodeficiency virus (HIV)

- Less than 4 weeks elapsed since any major surgery

- Any prior or active disease that may interfere with the procedures or evaluations to
be conducted in the study