Randomized Controlled Trial of Subcutaneous Epoetin Alfa-epbx Versus Epoetin Alfa in End-Stage Kidney Disease

Abstract

Introduction: This double-blind, randomized controlled trial compared the safety and efficacy of subcutaneous epoetin alfa-epbx, an epoetin alfa biosimilar, with the reference product, epoetin alfa, in hemodialysis patients with end-stage kidney disease (ESKD) and anemia who were receiving epoetin alfa maintenance treatment. Methods: Eligible patients (n = 320) were randomized (1:1) to subcutaneous epoetin alfa-epbx or epoetin alfa in a titration phase; patients who demonstrated stable subcutaneous dosing (n = 246) were re-randomized to receive subcutaneous epoetin alfa-epbx or epoetin alfa 1 to 3 times per week in a 16-week maintenance phase. Co-primary endpoints were least-squares mean difference between treatments in mean weekly hemoglobin concentration and mean weekly epoetin dose per kilogram body weight (BW) during the last 4 weeks of treatment in the maintenance phase. Results: The least-squares mean difference (95% confidence interval [CI]) between treatments in weekly hemoglobin was 0.04 g/dl (−0.17 to 0.24 g/dl) and weekly epoetin dose/kg BW was −2.34 U/kg per week (−14.51 to 9.82 U/kg per week). The 95% CIs were contained within the prespecified equivalence margins of ±0.5 g/dl (weekly hemoglobin) and ±45 U/kg per week (weekly epoetin dose/kg BW). In the epoetin alfa-epbx and epoetin alfa groups, respectively, 4.0% and 4.1% of patients required blood transfusions, 69.7% and 70.5% reported adverse events, 18.9% and 27.0% reported serious adverse events, and 3 and 2 deaths were reported. Five patients were confirmed positive for anti-recombinant human erythropoietin antibody, 2 of whom tested positive at baseline. All patients tested negative for neutralizing antibodies. Conclusions: This comparative clinical trial demonstrated equivalence in efficacy and similar safety of subcutaneously administered epoetin alfa-epbx to epoetin alfa. Keywords: biosimilar, efficacy, end-stage kidney disease, epoetin alfa, subcutaneous administration, safety