Introduction

Chemotherapy-induced anemia (CIA) is a frequent complication of breast cancer patients that is associated with fatigue and impaired quality of life. Biosimilars of erythropoietin-stimulating agents have now been approved to treat CIA in Europe. The ORHEO (biOsimilaRs in the management of anaemia secondary to chemotherapy in HaEmatology and Oncology) study was an observational study conducted in France to evaluate the efficacy and safety of a biosimilar epoetin alfa in an oncology setting. The large number of patients who enrolled in the study permitted indication-specific subanalyses to be undertaken. Herein we report the results of the subanalysis that focuses on the subpopulation of breast cancer patients.

Methods

The ORHEO study was a prospective, observational, longitudinal, multicenter postmarketing study. Patients ≥18 years with CIA (hemoglobin [Hb] <11 g/dL)-associated solid tumors, lymphomas, or myelomas who were eligible for treatment with an epoetin alfa biosimilar were enrolled. The primary endpoint was Hb response (defined as Hb reaching ≥10 g/dL, an increase of Hb ≥1 g/dL since inclusion, or reaching target Hb) measured at 3 and 6 months (M3 and M6, respectively). Secondary endpoints included safety and tolerability. Only breast cancer patients with CIA were included in this subanalysis.

Results

The ORHEO study enrolled 2333 patients; of these, 266 patients presented with CIA associated with breast cancer and were included in this subanalysis. The mean age was 61 years, the majority had ECOG PS 1 (51.5%) and metastatic disease (56.0%), and 99.6% received an epoetin alfa biosimilar. At baseline, the mean Hb level was 9.9 g/dL. At the M3 and M6 time points, an Hb response was observed in 86.8% and 91.7% of patients, respectively; average Hb levels increased by 1.3 g/dL (M3) and 1.8 g/dL (M6). By M3, 44% of patients reached their target Hb level; this increased to 53.7% at M6. At M3 and M6, of those patients who definitively or temporarily discontinued treatment, over half did so because the target Hb had been reached (M3: 55.6% [n = 74/133]; M6: 53.2% [n = 81/152]). Clinically significant adverse events (AEs) were observed in 9.9% of patients; the most common AE was infection (7.9%), while thrombotic events were only reported in 0.8% of patients. High baseline systolic blood pressure, high hematocrit levels at M3, and clinical improvement by M3 were identified as potential indicators of a positive response to an epoetin alfa biosimilar.

Conclusion

This subanalysis of the large ORHEO observational study has demonstrated the utility of biosimilar epoetin alfa in a real-world setting. Biosimilar epoetin alfa was seen to be efficacious and well tolerated in patients with breast cancer who presented with CIA, and no new safety signals were identified in this subpopulation. These data support the results observed in the parent ORHEO study, and confirm that biosimilar epoetin alfa (Hospira) is a therapeutic alternative for treating CIA in patients with breast cancer. Several potential prognostic indicators were identified that may warrant further study.

Citation Format: Albrand H, Luporsi E, Michallet M, Soubeyran P. Usage of epoetin alfa biosimilars in the management of chemotherapy-induced anemia in patients with breast cancer: A subanalysis of the ORHEO study. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P1-10-02.