Darbepoetin alfa administered once monthly maintains hemoglobin concentrations in patients with chronic kidney disease

Background: Darbepoetin alfa is an erythropoiesis-stimulating glycoprotein that functions by the same mechanism as recombinant human erythropoietin (rHuEPO), but has a three-fold longer serum half-life. Reduction in the frequency of darbepoetin alfa administration would be beneficial to patients with renal disease and their healthcare providers. This study evaluated the effect of extending the darbepoetin alfa dosing interval to once monthly in patients with chronic kidney disease (CKD) not receiving dialysis. Methods: This study was a multicenter, open-label study of 97 patients with CKD not on dialysis. Patients receiving stable subcutaneous doses of darbepoetin alfa once every two weeks were converted to darbepoetin alfa once monthly for 29 weeks. The proportion of patients who successfully maintained hemoglobin concentrations between 10.0 and 12.0 g/dl and the mean darbepoetin alfa dose were evaluated. Safety measurements (e.g. adverse events, laboratory parameters, blood pressure) and seroreactivity were assessed. Results: Hemoglobin concentration was maintained within the target range in 79% (95% confidence interval (CI) = 71% to 87%) of all patients receiving darbepoetin alfa and in 85% (95% Cl = 78%-93%) of patients who completed the study period. The mean standard deviation monthly darbepoctin alfa dose was similar between baseline (88.7 +/- 49.9 mu g) and the evaluation period (86.6 +/- 78.8 mu g). The safety profile for monthly darbepoetin alfa administration was comparable with that previously observed with more-frequent administration. Conclusion: Patients with CKD who are clinically stable on darbepoetin alfa administered once every two weeks can be safety and effectively converted to darbepoetin alfa administered once monthly.