Purpose: This is a single-center uncontrolled retrospective study to evaluate the efficacy and safety of the biosimilar epoetin zeta after approval in chemotherapy-induced anemia (CIA).
Methods: Patients screened were >18 years old suffering from solid malignancies and CIA with Hg ≤10 or <11 g/dl if symptomatic anemia. Patients had measurable disease by TNM and Eastern Cooperative Oncology Group (ECOG). Patients were treated for at least 12 weeks and the primary endpoint was to determine the incidence of blood transfusions, and secondarily, the overall safety and efficacy defined as ≥1 g/dl rise in Hb concentration or ≥40,000 cells/μl rise in reticulocyte count. Quality of life was assessed with ECOG performance status (PS) and functional assessment of cancer therapy-anemia (FACT-An) score.
Results: 1287 patients with median Hb 9.3 g/dl (range 8.3-10.6) were enrolled and included in the evaluation. Median age was 63 years (range 33-78). 74% of patients were stage III/IV. Patients received epoetin zeta subcutaneously at fixed 40,000-IU once weekly. Blood transfusions were given in 178 patients (13.8%; 95% CI 11.9-15.6%). Appropriate response was observed in 79% patients by week 4, 87% by week 8, and 91% by week 12. A mean Hb increase of 2.5 g/dl was observed by week 12 which correlated with an improvement in PS and Fact-An score. Thrombotic events occurred in 5.2% (95% CI 3.4-7.1%) of patients.
Conclusions: Epoetin zeta is effective in palliation and treatment of CIA in patients with solid tumors. Overall, it is well tolerated and safe even in patients with increased disease burden.
Keywords: Anemia; Biosimilar; Chemotherapy; Epoetin zeta; Erythropoietin; Quality of life.