A randomized controlled study comparing once-weekly to every-2-week and every-4-week dosing of epoetin alfa in CKD patients with anemia

Abstract

Background and objectives: Extended-interval dosing of epoetin alfa (EPO) is commonly used to treat anemia in patients with chronic kidney disease (CKD). This study aimed to demonstrate that EPO dosed every 2 weeks (Q2W) and every 4 weeks (Q4W) was noninferior to once-weekly (QW) dosing.

Design, setting, participants, & measurements: 430 anemic subjects with stage 3 to 4 CKD receiving a stable QW dose of EPO were randomized 1:1:2 to QW, Q2W, and Q4W dosing for 36 weeks. Hemoglobin (Hb) was measured weekly, and the dose of EPO was adjusted to maintain an Hb level of 11.0 to 11.9 g/dl. The primary endpoint was change in Hb from baseline to the average of the last 12 weeks of treatment.

Results: Both the Q2W and Q4W dosing groups were noninferior to the QW group. The estimated difference of the mean change in Hb between Q2W and QW was -0.03 g/dl; and between Q4W and QW was -0.09 g/dl. From weeks 13 to 37, the mean percentage of weeks per subject with Hb 10.0 to 11.9 g/dl, inclusive, was 81% for QW, 81% for Q2W, and 75% for Q4W. Death occurred, respectively, in 4%, 3%, and 4%; thromboembolic vascular events occurred in 3%, 5%, and 3%; and serious adverse events occurred in 22%, 26%, and 26% of subjects.

Conclusions: Q2W and Q4W EPO dosing maintained Hb levels in subjects with stage 3 to 4 CKD. Deaths, thromboembolic vascular events, and serious adverse events were comparable across the dosing groups.

Figure 1.

Subject disposition. ITT, intent to treat; mITT, modified ITT; mITT population^a, subjects who were randomized and had at least one postrandomization Hb value; Per-protocol population^b, subjects who received at least 75% of the intended doses before withdrawal from the study or initiation of dialysis, whichever occurred earlier, and who had no major protocol deviations.

Figure 2.

Mean Hb during weeks 1 to 37 of treatment by EPO treatment groups.