ORTHO’s EPREX REDUCES AIDS TRANFUSION REQUIREMENTS BY 43%

ORTHO's EPREX REDUCES AIDS TRANFUSION REQUIREMENTS BY 43% in cases of AZT-induced anemia compared to placebo, according to results of a Phase III trial of 63 patients published in the May 24 issue of The New England Journal of Medicine. By the end of three months of therapy, patients in the EPO group required 1.48 units per month of packed red cells or whole blood transfused compared to 2.58 for the placebo group. In the study conducted by Margaret Fischl, MD, et al., University of Miami, Florida, patients received a 12-week regimen of 100 U/kg of erythropoietin three times weekly in an intravenous bolus. The overall number of units transfused per month decreased by 26% in the EPO group over the 12-week period, while the number increased by 38% in the placebo group. Although there was an overall decrease in the patients' transfusion requirements, the benefit was restricted to the group of patients with endogenous EPO serum levels of less than 500 IU/I. In the low endogenous EPO group, Eprex reduced the number of units of blood required per month by 69% compared to placebo, 0.84 versus 2.74. From baseline, the tranfusion requirement in those patients decreased 36% in the EPO group, from 1.31 to 0.84, while the number in the placebo group increased by 63%, from 1.68 to 2.74. In patients with endogenous serum EPO levels of greater than 500 IU/1, the transfusion requirement increased by 26% for the EPO group compared to placebo, 3.50 versus 2.78, with an increase from baseline in the EPO group of 13%. The transfusion requirement in the placebo group of patients with high endogenous EPO actually decreased by 16%. While hematocrit and level of hemogloblin (usual criteria for EPO efficacy) were not used as primary endpoints in the study because transfusions were given at the discretion of physicians, patients with low levels of endogenous EPO at baseline had a significantly higher rate of increase in their hematocrit at 12 weeks compared to placebo. There was no statistically significant difference in hematocrit between EPO and placebo in patients with endogenous EPO levels higher than 500 IU/1. The researchers hypothesized that AZT may induce two distinct types of anemia, one of which may not respond to EPO therapy. Two other studies presented at the May 22 meeting of the American Society of Clinical Oncology in Washington, D.C. showed that Eprex also addresses anemia in cancer patients. In the first study, conducted by the Graduate Hospital of Philadephia, 69 patients receiving cisplatin chemotherapy were given 150 U/kg subcutaneously three times weekly for 12 weeks. Analysis of data from 52 of the patients showed that Eprex was statistically significant in increasing the patients' hematocrits by 6.7% compared to 2% for placebo. The number of patients requiring tranfusions were fewer in the EPO group than in the placebo group, 10 (39%) versus 15 (60%), although the difference was not statistically significant. In addition, 62% of EPO patients reached the target hematocrit of 38% without a tranfusion during the prior month compared to 15% of placebo patients. The second study was a Phase III trial conducted by Ortho Pharmaceutical Corporation Research Group in 53 cancer patients who had never received chemotherapy or who had failed chemotherapy and were not receiving treatment at the time of the study. The patients received 100 U/kg subcutaneously three times weekly for eight weeks. By the fourth week of therapy, there was a statistical difference in the hematocrit between the EPO group and the placebo group. At the end of eight weeks, 26% of the EPO patients had corrected hematocrits (equal to or greater than 38%) compared to 5% of the placebo patients. Hematocrits were raised by six points or more, or to 38%, in 35% of the EPO patients compared to 10% of placebo patients. The results of EPO therapy in the cancer patients not receiving chemotherapy were somewhat below expectations, Ortho researcher Seth Rudnick, MD, commented. The investigators had expected "those numbers [would] be roughly 50%," Rudnick said, explaining that by using a dose of 100 U/kg instead of the usual 150 U/kg, "we may perhaps have slightly underdosed these patients." However, he noted that "the transfusion requirement appears to decrease and the quality of life appears to increase in this group of patients." At the end of a four-week period, the transfusion requirement was 0.8 units in the EPO group and 1.2 units in the placebo group.