Conversion from epoetin alfa to darbepoetin alfa within the Manitoba Renal Program: evaluation of dose ratios.

We sought to describe dose conversion ratios between epoetin alfa and darbepoetin alfa for patients with anemia of chronic kidney disease (CKD) in a large provincial renal program. Hemodialysis (HD), peritoneal dialysis (PD) and pre-dialysis patients with CKD were included. Laboratory parameters and darbepoetin alfa doses were compared to epoetin alfa doses (same route). In 2005, 857 patients received darbepoetin alfa and were compared to 746 patients who received epoetin alfa in 2003-2004. Mean dose conversion ratios were 12,939 IU, 53.1 microg, 244:1 for HD; 9,273 IU, 41.8 microg, 222:1 for PD; and 5,516 IU, 25.2 microg and 219:1 for CKD patients. The mean hemoglobin and iron parameters were within K/DOQI targets on both drugs. Conversion ratios in HD, PD and CKD patients using erythropoietic therapies was greater than 200:1 with both intravenous and subcutaneous dosing. Renal programs across Canada should consider dosage conversion ratios in addition to drug acquisition costs when considering a formulary decision about erythropoiesis stimulating agents.