A Randomized Comparison of Every-2-Week Darbepoetin Alfa and Weekly Epoetin Alfa for the Treatment of Chemotherapy-Induced Anemia in Patients With Breast, Lung, or Gynecologic Cancer

Abstract

An important clinical question is the relative efficacy of the most common dosages of darbepoetin alfa (Aranesp; Amgen Inc.; Thousand Oaks, CA) 200 microg every 2 weeks (Q2W) and epoetin alfa (Procrit; Ortho Biotech Products, LP; Raritan, NJ) 40,000 U weekly (QW) for the treatment of chemotherapy-induced anemia. We designed three concurrent randomized, open-label, multicenter, identical trials (with the exception of tumor type criteria of breast, gynecologic, or lung cancer) of darbepoetin alfa and epoetin alfa in patients with chemotherapy-induced anemia to validate the Patient Satisfaction Questionnaire for Anemia (PSQ-An) treatment tool and to compare the efficacies and safety profiles of these two agents. In each trial, patients were randomized 1:1 to receive either darbepoetin alfa at a dose of 200 microg Q2W or epoetin alfa at a dose of 40,000 U QW for up to 16 weeks. The PSQ-An was assessed for validity, feasibility, and reliability. Secondary clinical endpoints were analyzed using the primary analysis set. Both individual trial analyses and a protocol-specified combined analysis of data from all three trials were conducted. Overall, 312 patients (157 darbepoetin alfa; 155 epoetin alfa) were randomized and received study drug. Baseline characteristics were similar in both treatment groups in each trial and overall. The PSQ-An was valid, feasible, and reliable. In general, no difference between treatment groups was observed for hemoglobin- and transfusion-based endpoints in each individual trial or in the combined analysis. From exploratory analyses, achievement and maintenance of a hemoglobin target range (11-13 g/dl) were similar in both groups. No differences in safety were observed. With the PSQ-An, formal comparisons of the impact of anemia therapies on patients and caregivers can be made in future prospective studies. Further, darbepoetin alfa (200 microg Q2W) and epoetin alfa (40,000 U QW) appear to achieve comparable clinical and hematologic outcomes.