Abstract
INTRODUCTION: Chemotherapy-induced anemia (CIA) is a frequent complication among cancer patients, with elderly patients more likely to suffer severe effects. Biosimilar erythropoiesis-stimulating agents lower costs of supportive cancer treatment, and thus are particularly relevant in the elderly cancer population, which is growing rapidly worldwide. The goal of this subanalysis was to compare the tolerability and effectiveness of an epoetin biosimilar for treating CIA in patients <70 years old vs patients ≥70 years old. MATERIALS AND METHODS: The ORHEO observational trial enrolled patients with CIA (hemoglobin [Hb] <11 g/dL) in association with chemotherapy for solid tumors, lymphoma, or myeloma. Patients received an epoetin biosimilar and were evaluated at 3 and 6 months for response, defined as achieving target Hb without blood transfusions during the 3 weeks preceding measurement, Hb ≥10 g/dL, or Hb increase ≥1 g/dL since study enrollment. Secondary end points included changes in Hb level, treatment interruptions, transfusion rates, and adverse events. RESULTS: Among the 2,310 original patients, 1,301 <70 years old were compared to 1,009 ≥70 years old. Almost all patients (99.9%) received the biosimilar epoetin zeta (Retacrit). Patients in both groups responded well to treatment with biosimilar epoetin, with 79.8% and 84% responding at 3 months and 86.3% and 86.8% at 6 months among younger and elderly cohorts, respectively. Biosimilar epoetin therapy was well tolerated, with adverse events reported in only 17.6% and 16.4% of younger and elderly patients, respectively. A greater number of thromboembolic events and a lesser rate of infections were reported in the elderly, but were still lower than reported in clinical registration trials. No treatment fatalities occurred in either group. CONCLUSION: Biosimilar epoetin was an effective and well-tolerated treatment for managing CIA in elderly cancer patients.