Switching from Epoetin Alpha to Darbepoetin Alpha in Japanese Hemodialysis Patients: Dose Conversion Ratio

Abstract

Background/Aims: Darbepoetin alpha is an erythropoietic agent with a 3-fold longer elimination half-life than epoetin. The recommended conversion ratio from epoetin to darbepoetin alpha is 1:200 (1 μg of darbepoetin alpha = 200 IU of epoetin), but several observations have suggested that this ratio overestimates the required dose of darbepoetin alpha. This study assessed the actual conversion ratio for stable Japanese hemodialysis patients and investigated whether darbepoetin alpha promotes uniform erythropoiesis. Methods: A total of 104 hemodialysis patients who were stable on epoetin alpha therapy at Hakuai Clinic in Japan were switched to intravenous darbepoetin alpha according to the 1:200 rule. They were followed for 24 weeks to assess changes of hemoglobin and the dose of darbepoetin alpha, as well as changes of the reticulocyte count. Results: One hundred patients completed the 24-week study and the final conversion ratio was 1:350.5. Darbepoetin alpha showed a similar effect in diabetics and nondiabetics. Data on the reticulocyte count demonstrated that darbepoetin alpha had a sustained effect on erythropoiesis. Conclusion: Darbepoetin alpha is effective for Japanese dialysis patients at a lower dose than expected.