Inclusion Criteria:

1. Histologically confirmed de novo or secondary MDS.

2. Age ≥ 18 years.

3. Eastern Cooperative Oncology Group (ECOG) performance status of 0, 1, or 2.

4. Adequate renal and hepatic function (creatinine ≤ 2.0 mg/dL, total bilirubin < 2.0
mg/dL, aspartate aminotransferase [AST] or alanine aminotransferase [ALT] < 3 times
the upper limit of normal).

5. Life expectancy of at least 6 weeks.

6. If currently receiving 5 day decitabine regimen, patient must be scheduled to receive
one more cycle of 5 day decitabine.

7. Recovered from all toxic effects of all prior therapy before entry into this study.

8. Women of childbearing potential and all men must agree to practice a medically
approved form of contraception (one of the following must be used: condoms [male or
female] with a spermicidal agent, diaphragm or cervical cap with a spermicidal agent,
intrauterine device, hormonal contraception, abstinence) during the course of the
study and up to 2 months following the last dose of decitabine.

Exclusion Criteria:

1. Candidates for up front high dose induction chemotherapy. MDS patients who are
scheduled to receive decitabine prior to a bone marrow transplant or stem cell
transplant are allowed.

2. History of treatment failure with decitabine.

3. Received any experimental agent within the preceding 30 days prior to screening.

4. Uncontrolled cardiac or pulmonary disease.

5. History of intestinal surgery, pancreatic surgery, or gastric surgery.

6. Any clinically relevant disease, disorder (including psychiatric disorders), or
condition, in the opinion of the Investigator, which may interfere with the
objectives of the study, especially with the gastrointestinal (GI) absorption of the
study drug, and/or with the safety of the subject in the study.

7. Current active colitis of any etiology (Clostridium difficile colitis, ulcerative
colitis, Crohn's disease, etc.) or a recent (< 2 weeks) episode of colitis.

8. Pregnant or lactating. Female patients of childbearing potential must have had a
negative serum pregnancy test at screening and a negative urine pregnancy test on Day
1 prior to dosing.

9. Known positive serology for human immunodeficiency virus (HIV).

10. Active viral, fungal, or bacterial infection. No patient may enter the study unless
infections have been fully treated.