| Inclusion Criteria: | 1) Histologically confirmed diagnosis of primary or de novo MDS using the World Health Organization (WHO) classification.
2) Low or intermediate-1 risk MDS using the International Prognostic Scoring System (IPSS).
3) World Health Organization (WHO) classification types of: refractory anemia (RA), refractory anemia with excess of blasts (RAEB-1), refractory anemia with ringed sideroblasts (RARS), refractory cytopenia with multilineage dysplasia (RCMD), refractory cytopenia with multilineage dysplasia with ringed sideroblasts (RCMD-RS), MDS-Unclassified (MDS-U), MDS/Myeloproliferative disorder-unclassified (MDS/MPD-U) without leukocytosis, and MDS with deletion of chromosome 5q (MDS-del5q).
4) >/= 18 years of age.
5) Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1.
6) Prior treatment with experimental or conventional treatment other than blood products (i.e., chemotherapeutic, immunosuppressive, cytoprotective or demethylating agents), at least a four-week (28 days) washout period is required.
7) Documented significant cytopenia for at least two months, defined by a) or b) and in addition, may have c) and/or d): a) Red blood cell (RBC) transfusion dependence is defined as requiring four or more units within an eight-week period for symptomatic anemia with a hemoglobin value of </= 9 g/dL, or b) baseline hemoglobin < 10 g/dL (defined as an average of at least two baseline values not influenced by RBC transfusions for at least seven days prior to study entry) and in addition may have,
8) (cont'd from 7) c) Thrombocytopenia with an average of two or more platelet counts </= 50,000/mcl (not influenced by platelet transfusions for at least 3 days) or a clinically significant hemorrhage requiring platelet transfusions, and/or d) absolute neutrophil count (ANC) </= 1,000/mcl, or a prior infection requiring intravenous (IV) antibiotics.
9) Adequate organ function as indicated by the following parameters: a) serum bilirubin </= 2.5 mg/dL (except when Gilbert's syndrome or MDS-related hemolysis is clearly documented and other liver function tests are normal); b) AST and ALT </= 3 times the upper limit of normal (ULN); c) serum creatinine </= 2 mg/dL or a calculated creatinine clearance of >/= 60 mL/min; blood urea nitrogen (BUN) </= 25 mg/100 mL.
10) Patients must have discontinued hematopoietic growth factors: erythropoietin, granulocyte colony stimulating factors (G-CSF), or granulocyte macrophage colony stimulating factors (GM-CSF) at least three weeks (21 days) prior to study entry.
11) Ineligible or unwilling to undergo stem cell bone marrow transplantation.
12) Women of childbearing potential and men capable of reproduction willing to practice effective method of birth control.
13) Written informed consent.
14) Willingness to comply with study procedures and follow-up. |