EPO biosimilar shows efficacy similar to epoetin alfa
Click Here to Manage Email Alerts
Results of a 24-week trial that compared biosimilar epoetin alfa-epbx and epoetin alfa in patients on hemodialysis showed no clinically meaningful difference in efficacy or safety between the two drugs.
Epoetin alfa-epbx, made by Hospira Inc., was approved by the FDA in May as a biosimilar of epoetin alfa (Amgen Inc.).
“Epoetin alfa-epbx is identical in amino acid sequence and similar in carbohydrate composition to the reference product, epoetin alfa,” wrote Steven Fishbane, MD, from the department of medicine at Hofstra Northwell School of Medicine in Hempstead, New York, and colleagues in the paper. “Our study was conducted to demonstrate the equivalence of epoetin alfa-epbx to epoetin alfa when administered intravenously (IV) to patients on hemodialysis with ESKD and anemia, on the basis of maintenance of hemoglobin levels and study drug dose requirements.” Safety and tolerability of epoetin alfa-epbx compared to epoetin alfa were also evaluated.
Study protocol
The protocol for the study, after some adjustments, required that patients be on stable IV epoetin alfa treatment for 4 weeks or longer before randomization. The target level of hemoglobin was 9.0211.0 g/dl to accommodate new FDA requirements for patients on epoetin alfa, Fishbane and the authors wrote. After completing the trial, patients could enter an open-label, long-term, safety study under a separate protocol, and be treated with epoetin alfa-epbx for up to an additional 48 weeks.
“For both efficacy and safety, I believe the trial was of sufficient duration to see possible differences,” Fishbane told Healio Nephrology.
During the 24-week trial, clinicians tracked hemoglobin, study drug dose per kilogram of body weight, vital signs, concomitant medications, adverse events, and transfusion information each week. Blood was collected and chemistry, hematology, coagulation panels and iron status were analyzed at screening, before initial dosing, monthly and at follow-up.
The trial went from December 2011 to February 2014.
Results
The comparison of the two anemia drugs showed little difference in terms of drug efficacy and safety, the researchers wrote. Seventy-five (24.9%) patients in the epoetin alfa-epbx group and 82 (27%) patients in the epoetin alfa group experienced an adverse event. Likewise, “At any time during the treatment period, 16 (5.3%) and 33 (10.9%) patients receiving epoetin alfa-epbx and epoetin alfa, respectively, had hemoglobin levels [less than] 8 g/dl and 65 (21.6%) and 70 (23%) patients, respectively, had hemoglobin levels [greater than] 12 g/dl. Thus, [greater than or equal to] 73.1% of patients receiving epoetin alfa-epbx and [greater than or equal to] 66.1% receiving epoetin alfa did not have hemoglobin levels [less than] 8 g/dl or [greater than] 12 g/dl.”
Throughout the treatment period, “iron stores were replete and able to support erythropoiesis stimulated by epoetin for both groups. Furthermore, mean change from baseline to week 24 in C-reactive protein was similar between epoetin alfa-epbx (0.209 mg/dl) and epoetin alfa (0.300 mg/dl), and clinically unremarkable in the setting of patients with ESKD on hemodialysis,” the authors wrote.
“There was no other type of reaction, or any reaction seen with first or later use” of epoetin alfa-epbx, Fishbane told Healio Nephrology. “The FDA’s pathway for biosimilar development leads to rigorous testing for true biosimiliarity. The foundational, rigorous demands for protein, carbohydrate, pharmacokinetic, pharmacodynamics characterization leaves us with highly similar compounds by the time clinical testing takes place and makes any clinical differences highly unlikely even before study. With the studies concluded, it is good to see this was confirmed,” he said.
Disclosures: This study was funded by Hospira Inc., which was acquired by Pfizer Inc. in September 2015. Medical writing support was provided by the Camden Group and was funded by Hospira Inc. Three authors of the paper are either an employee or have been an employee of Hospira and/or own or have owned stock or options in Hospira, or have served on the company advisory boards.