Dose equivalence and hemoglobin stability on conversion from epoetin to darbepoetin alfa in hemodialysis patients

In a recent study, it was suggested that in patients undergoing hemodialysis, the conversion of epoetin alfa to darbepoetin alfa meant that achieving hemoglobin (Hb) stability was possible at a conversion ratio of 300:1 for patients receiving low doses of epoetin alfa and 350:1 for those receiving higher doses. This study was published in the International Journal of Nephrology and Renovascular Disease.

In this multicenter, observational, retrospective study, 125 patients above 18 years of age, who were switched from intravenous (IV) epoetin alfa to IV darbepoetin alfa, were included. They were on hemodialysis from month 0 to at least 24 months. The dose conversion was adjusted to maintain Hb within 1.0 g/dL of baseline.

At the end of the study, it was observed that there were no significant changes in Hb levels. The erythropoiesis-stimulating agent (ESA) dose decreased significantly after conversion from epoetin to darbepoetin alfa. With epoetin, an annual mean of 174.7 international units (IU)/kg/week was achieved while it was 95.7 and 91.4 IU/kg/week during the first and second year, respectively for darbepoetin.

Based on the above results, it can be concluded that to maintain Hb stability, a conversion ratio of 300:1 may seem appropriate for patients who received low doses of epoetin while a ratio of 350:1 may seem better for those receiving higher doses.