Biosimilar Shows Promise Treating Chemotherapy-Induced Anemia in Elderly Patients

The biosimilar erythropoiesis-stimulating agent (ESA) epoetin was well-tolerated and efficacious in the treatment of geriatric patients with chemotherapy-induced anemia (CIA), a recent study found.

CIA is a common complication among cancer patients, particularly older individuals. Biosimilar ESAs can lower the costs of supportive cancer treatments for this patient population. In a subanalysis published in Dove Press, investigators compared the efficacy and tolerability of an epoetin biosimilar for the treatment of CIA in patients <70 years versus patients ≥70 years.

Patients with CIA (hemoglobin [Hb] <11 g/dL) in association with chemotherapy for solid tumors, lymphoma, or myeloma, were enrolled in the ORHEO observational trial. Participants were administered an epoetin biosimilar, and were evaluated at 3 and 6 months for a response.

A response was defined in the study 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.

The secondary endpoints were changes in Hb level, transfusion rates, treatment interruptions, and adverse events (AEs), according to the study.

All statistical analyses were conducted on the per protocol population, which excluded patients with missing baseline Hb values, patients for whom age was not recorded, patients who had not initiated chemotherapy at baseline, patients who were not receiving an epoetin biosimilar at baseline, and patients who switched to another epoetin treatment between baseline and 6 months.

ORHEO is a large, observational, non-interventional, longitudinal, national, multi-center study that included 2333 patients from 235 centers.

At baseline, 2.2% of patients had grade 0 anemia (Hb ≥11 g/dL), 57.9% had grade 1 anemia (Hb 9.5—11 g/dL), 35.6% had grade 2 anemia (Hb 8–9.5 g/dL), 4% had grade 3 (severe) anemia (Hb 6.5–8 g/dL), and 0.3% had grade 4 (very severe) anemia (Hb <6.5 g/dL).

Hb response was achieved in 81.6% and 86.5% of patients at 3 and 6 months, respectively. Overall mean (±standard deviation) change in Hb level was 1.52±1.61 g/dL, and 1.72±1.61 g/dL at 3 and 6 months, respectively.

Investigators compared 1301 patients <70 years with 1009 patients ≥70 years. Nearly all of the patients received the biosimilar epoetin zeta (Retacrit).

The results of the study showed that both the younger and older cohorts responded well to treatment, with 79.8% and 84%, respectively, responding at 3 months, and 86.3% and 86.8%, respectively, responding at 6 months.

AEs from biosimilar epoetin therapy were reported in only 17.6% of younger patients and 16.4% of elderly patients. There were a greater amount of thromboembolic events and a lesser rate of infections reported in the elderly, but these were still lower than reported in clinical registration trials. No treatment-induced deaths occurred in either group.

The findings indicate that biosimilar epoetin is a safe and effective treatment option for anemia in elderly patients with CIA. The authors noted that although there was an increased incidence of thromboembolic events in the elderly population, the numbers were small, and there were no pulmonary embolisms or fatalities.

Overall, the data supports the need for physicians to better implement the use of biosimilar ESAs in older cancer patients, according to the study.