Study results suggest that 80,000 units of epoetin alfa (Epogen, Procrit) administered once every 2 weeks demonstrated comparable changes in hemoglobin levels and safety in treating chemotherapy-related anemia in patients with nonmyeloid malignancies compared to 40,000 units of epoetin alfa once weekly, the current recommended dosage. This study, the first of its kind to evaluate an extended initiation dose of epoetin alfa in this population, was presented at the 2006 American Society of Clinical Oncology (ASCO) annual meeting.
The randomized, open-label, multicenter study compared the response of study patients to 80,000 units of epoetin alfa dosed once every 2 weeks with 40,000 units once weekly. The primary endpoint was the comparison of baseline-to-final hemoglobin levels between the two treatment groups. Secondary endpoints included the assessment of hemoglobin response, time to hemoglobin response, transfusion requirements, and safety.
A total of 310 patients with nonmyeloid malignancy were enrolled in the study. At entry, patients had hemoglobin levels less than or equal to 11 g/dL of blood and were scheduled to undergo chemotherapy for a minimum of 12 weeks. The patients were randomly assigned to receive one of the two dosing regimens subcutaneously for up to 12 weeks, with dose modifications to maintain hemoglobin levels at approximately 12 g/dL of blood. Breast, lung, and colorectal cancer were the most common tumor types at study entry. Almost 50% of patients in each group received platinum-containing chemotherapeutic agents.
The average change in hemoglobin levels from the start to the end of the study in the group dosed with 80,000 units every 2 weeks was 1.6 g/dL of blood. This was statistically comparable to the increase of 1.8 g/dL of blood achieved by the group dosed with 40,000 units weekly. Additionally, of the patients dosed once every 2 weeks, 9.6% required a transfusion between day 29 and the end of the study compared with 11.1% in the patients dosed weekly.
Seventeen patients in each treatment group were withdrawn from the study due to adverse events, most of which were related to the patient's underlying cancer or chemotherapy. The most frequently reported adverse events were diarrhea, nausea, and fatigue. Clinically relevant thrombotic vascular events occurred in 8% of patients in each group. Nineteen patients died during the study or within 30 days of the last dose of study drug, all of which were deemed by the investigators to be unrelated to the study drug.