HIGH-DOSES OF INTRAVENOUS RECOMBINANT ERYTHROPOIETIN FOR THE TREATMENT OF ANEMIA IN MYELODYSPLASTIC SYNDROME

We studied the efficacy of high doses (100 000 IU intravenously (IV)/twice a week) of human recombinant erythropoietin (rHuEpo) in patients with transfusion dependent myelodysplastic syndromes (MDS). Rationale for such dose of IV Epo was the poor in vitro response of MDS erythroid progenitors (CFU-E) to physiological concentrations of Epo, and the usual high endogenous serum Epo levels of MDS patients. Seventeen patients (nine mates, eight females) were included, five refractory anaemia (RA), six RA with blasts excess (RAEB), five RA with ringed sideroblasts (RARS). Tolerance was good, except in three patients who experienced severe flu-like syndrome after Epo injection. None of the patients showed hypertension or developed anti rHuEpo antibodies. Three patients (17.6%) with RAEB had 35-60% reduction of transfusion requirements. No progression of disease occurred. Percentage of erythroblasts, endogenous baseline Epo level and in vitro cultures of erythroid progenitors did not correlate with response to Epo treatment. This study shows that very high IV doses induce only seldom and partial improvement in the status of transfusion dependent MDS. This rate of response, not higher than described with lower dosage, probably represents the maximum expectable response to rHuEpo in this category of patients.