Pharmacokinetic Guided Dose Escalation and Dose Confirmation With Oral Decitabine and Oral Cytidine Deaminase Inhibitor (CDAi) in Patients With Myelodysplastic Syndromes (MDS)

Inclusion Criteria: * International Prognostic Scoring System (IPSS) low, intermediate -1, intermediate-2, or high risk MDS (including chronic myelomonocytic leukemia; CMML) in Dose Escalation and Dose Confirmation-Randomization; only intermediate-2, or high risk MDS in Dose Confirmation-Open Label * Eastern Cooperative Oncology Group (ECOG) 0 to 2 * No major surgery within 2 weeks of starting study treatment * No cytotoxic chemotherapy within 2 weeks of starting study treatment * Able to swallow pills Exclusion Criteria: * Previous treatment with 2 or more courses of decitabine (all stages) or azacitidine (Dose Confirmation stage only) * Treatment with investigational therapy within 2 weeks of study treatment * Uncontrolled medical disease(s) or active, uncontrolled infection * Diagnosed with acute myeloid leukemia (AML) * Active uncontrolled gastric or duodenal ulcer * Known history of HIV or hepatitis C or B