Treatment of the anemia of aplastic anemia patients with recombinant human erythropoietin in combination with granulocyte colony ‐ stimulating factor: a multicenter randomized controlled study

Abstract

A multicenter randomized controlled study was undertaken in order to determine whether epoetin beta (EPO) ameliorates the anemia in aplastic anemia (AA) patients treated with granulocyte colony-stimulating factor (G–CSF). Enrolled patients were randomized into 3 groups: group C receiving G–CSF alone as the control; group L receiving G–CSF and 200 IU/kg of EPO; group H receiving G–CSF and 400 IU/kg of EPO. Throughout the study, the dose and the administration interval of G–CSF were adjusted to maintain neutrophil counts between 1000 and 5000 μl. EPO was administered subcutaneously for 12 wk as the first step in treatment and when favorable effects were observed over this period, treatment was continued for another 12 wk as the second step in treatment. Significant erythroid responses were defined as increases in untransfused hemoglobin values >1.0 g/dl or >50% decreases in RBC transfusion requirements over the treatment period. Of 131 patients enrolled, 88 patients allocated to groups L and H were evaluated for toxicity to EPO and 110 were evaluated for erythroid responses. Four of the 31 patients (12.9%) in group C, 6 of the 41 patients (14.6%) of group L, and 14 of the 38 patients (36.8%) of group H showed erythroid responses in the first step in treatment. The erythroid responses of group H were significantly higher than those of the other 2 groups (p<0.05). The significant effects of EPO were due to erythroid responses in non-severe AA. Responding patients were significantly different from non-responders with regard to disease severity, hemoglobin concentration, reticulocyte count, serum endogenous erythropoietin levels and serum transferrin receptors; non-severe AA patients were more likely to respond to EPO, and responding patients had lower serum EPO and higher hemoglobin concentration, reticulocyte count and serum transferrin receptors than non-responders. The response rate increased in the second step in treatment, suggesting that long-term treatment improved the efficacy of EPO. No serious side-effects were observed. From these results, we conclude that EPO given in combination with G–CSF is a safe and effective alternative for the treatment of anemia of a subset of AA patients.