Double-blind, placebo-controlled. Patients received intravenous REPO (1000 IU/kg) or placebo twice per week. The five patients in Group A had no transfusion history. The five patients in Group B had a history of transfusions. Prior to the study, the authors determined that treatment would continue for twelve weeks or until the hemoglobin reached 12.5 g/dl. After the twelve week study period, patients were eligible to receive open label erythropoietin (500 IU/kg, twice a week). For numerous reasons, recruitment of patients was a major problem in this trial. The study originally estimated a total of 64 patients.