|Exclusion Criteria:||1) Receiving any treatment for MDS other than transfusions or a stable dose (>/= 4 weeks) of hematopoietic growth factors on study Day 1.|
2) Treatment with any of the following: a. Azacitidine or decitabine: within 2 weeks prior to first dose of study treatment. b. Chronic use (> 2 weeks) of greater than physiologic doses of PO, subcutaneous (SC) or intravenous (IV) corticosteroids (dose equivalent to > 20 mg/day of prednisone): within 4 weeks prior to the first dose of study treatment. c. Immunomodulatory agent (e.g., lenalidomide): within 4 weeks prior to the first dose of study treatment.
3) History of a bone marrow transplant.
4) Concomitant malignancies or previous malignancies with less than a 2-year disease-free interval at the time of enrollment. Patients with adequately resected basal or squamous cell carcinoma of the skin, carcinoma in situ of the cervix, or Stage A low grade prostate cancer may enroll irrespective of the time of diagnosis.
5) Medical, psychiatric, cognitive or other conditions that may compromise the patient's ability to understand the patient information, to give informed consent, to comply with the study protocol, or to complete the study.
6) Any severe concurrent disease or condition (including active systemic infection, symptomatic congestive heart failure, unstable angina pectoris or cardiac arrhythmia) that, in the judgment of the Investigator, would make the patient inappropriate for study participation.
7) Patients with chronic myelomonocytic leukemia whose WBC count has been >/= 13.0 × 10^9/L at any point during the 8 weeks prior to the first dose of study drug.
8) Patients who require oral anticoagulants with coumarin derivates (e.g., warfarin, phenprocoumon), unless the patient is willing to allow for increased vigilance with respect to international normalized ratio (INR) testing per institutional monitoring practices.
9) 12-lead ECG demonstrating a QTcF of >/= 480 msec (mean of the triplicate ECG measurements) collected during Screening, with the exception of patients with atrioventricular pacemakers.
10) Significant GI abnormalities, including an inability to take oral medication, requirement for IV alimentation, active peptic ulcer, or prior surgical procedures affecting absorption.
11) Use of an investigational agent that is not expected to be cleared by the first dosing of study drug or that has demonstrated to have prolonged side effects. Patients should have recovered from the side effects to a Grade 0 or 1 (except alopecia).
12) Pregnant or lactating females.