| Inclusion Criteria: | 1) Diagnosis of severe aplastic anemia (bone marrow cellularity < 30%, with two of three peripheral counts at the time of initial presentation or within last 30 days prior to study drug with ANC < 500/mL, pre-transfusion PLT< 20,000/mL, or pre-transfusion hemoglobin < 8 g/dL and presence of no other underlying disorder.
2) Diagnosis of MDS (WHO) with bone marrow cellularity < 30%, with two of three peripheral counts at the time of initial presentation or within last 30 days prior to the study with ANC < 500/mL, pre-transfusion PLT < 20,000/mL, or pre-transfusion hemoglobin < 8 g/dL.
3) Patients with MDS who have received prior biological therapy (not chemotherapy) are eligible. Hypomethylating agents and histone deacetylase inhibitors are considered as biological therapy.
4) Age 15 or greater
5) Adequate renal function (creatinine less than or equal to 2.0 mg/dL) unless related to the disease
6) Adequate hepatic function (bilirubin less than or equal to 3.5 mg/dL) unless related to the disease
7) No other investigational therapy in the past 14 days
8) Able to sign consent form
9) Able to comply with the need for contraception (abstinence, condom, birth control pill, or other acceptable form of contraception) during the entire study period
10) Diagnosis of MDS (WHO) with bone marrow cellularity greater than 30%, with low or intermediate-1 risk by the IPSS score, and requiring treatment (i.e. transfusion-dependent) |