Effect of darbepoetin alfa on renal anemia in Japanese hemodialysis patients.

Introduction: A long-acting erythropoiesis-stimulating agent named "darbepoetin alfa" (CAS 11096-26-7) was recently developed. Though it is already in use worldwide, especially in western countries, its efficacy and safety for Asian patients have not been well evaluated yet. The purpose of this study was to evaluate the efficacy and safety of short-term darbepoetin alfa administration for Japanese hemodialysis patients. Methods: Patients who had undergone maintenance hemodialysis were enrolled in this study. The erythropoiesis-stimulating agent was switched from epoetin alfa (CAS 113427-24-0) to darbepoetin alfa so as to control the hemoglobin (Hgb) value between 10 and 12 g/dl. The initial conversion ratio was made according to the manufacturer's recommendations. The factors relevant to the responsiveness to erythropoiesis were analyzed. Results: One hundred and fifty-nine patients with a mean age of 67.6 years were enrolled. Two months after switching to darbepoetin alfa, the Hgb value had increased significantly (10.3 +/- 1.2 to 10.6 +/- 1.4 g/dl). Only iron supplementation correlated positively with the change of Hgb. In addition, 14.3% of patients had excess Hgb (Hgb > 12 g/dl) at the end of the study period, but only 5.6% patients at the run-in. Serious cardiovascular disease did not occur during the study period; however, the mean systolic blood pressure at the start of hemodialysis increased significantly and there was no correlation between the change of Hgb value and blood pressure. Conclusion: Darbepoetin alfa, increases the Hgb value effectively in Japanese hemodialysis patients. Although no serious adverse events were apparent in our short-term analysis, the incidence of hypertension and excessive increase of the Hgb value must be noted.