Efficacy of Epoetin Alfa in a Retrospective Non-stratified Subgroup Analysis of a Breast Cancer Cohort Receiving Non-platinum Chemotherapy

Abstract

More than 60% of patients with metastatic breast cancer receiving non-platinum-based chemotherapy experience anemia, which is associated with fatigue and impaired quality of life. Epoetin alfa treatment in patients with a variety of malignancies has been shown to decrease transfusion requirements and improve hemoglobin levels and quality-of-life efficacy parameters. Retrospective subgroup analyses were performed in patients with breast cancer who were part of a multinational, randomized (2:1), double-blind, placebo-controlled trial of anemic cancer patients (n = 375) undergoing non-platinum-based chemotherapy. In the breast cancer subpopulation (n = 114, 48% with stage IV disease at baseline), the hemoglobin increase was greater for epoetin alfa patients than placebo patients (2.3 versus 0.9 g/dL). Epoetin alfa patients had lower transfusion requirements (28.2% versus 33.3%), improvement or preservation versus deterioration of quality of life, and a higher proportion of responders (patients achieving a > or = 2 g/dL increase in hemoglobin levels unrelated to transfusion) (68.0% versus 22.9% for placebo). The results were similar to those observed in the full study cohort, where statistical analyses showed the differences to be significant (P <0.05 for all). Epoetin alfa treatment was well tolerated. Although the study was not designed or powered for survival as an endpoint, Kaplan-Meier estimates for the full cohort showed a trend in overall survival favoring epoetin alfa treatment (P = 0.13, log rank test); a similar benefit was seen in the breast cancer subpopulation. In the full study cohort and the breast cancer subpopulation, epoetin alfa effectively treated anemia (increased hemoglobin levels and decreased transfusion requirements) and improved or preserved quality of life. Results concerning potential survival benefits support further study of epoetin alfa in anemic cancer patients.