Safety and Efficacy of Darbepoetin Alfa in Previously Untreated Extensive-Stage Small-Cell Lung Cancer Treated With Platinum Plus Etoposide

Abstract

A placebo-controlled, double-blind, randomized, phase III study was conducted in patients with extensive-stage small-cell lung cancer receiving first-line platinum-containing chemotherapy to determine if increasing or maintaining hemoglobin concentration with darbepoetin alpha could increase patient survival. Darbepoetin alpha (300 microg) or placebo was administered once per week for 4 weeks then every 3 weeks for up to six cycles of chemotherapy (carboplatin plus etoposide or cisplatin plus etoposide) plus 3 weeks after the last dose of chemotherapy. Patients with disease progression were observed until death or until all patients completed their end-of-study visit and 496 deaths had occurred. The two coprimary end points were change in hemoglobin concentration from baseline to the end of the chemotherapy period and overall survival; statistical testing of survival was done if change in hemoglobin was significant at P < .05. The study enrolled 600 patients. Patients' hemoglobin levels dropped due to the myelosuppressive chemotherapy; however, treatment with darbepoetin alpha maintained hemoglobin levels significantly higher than placebo (P < .001). There was no statistically significant difference in overall survival between the treatment groups (hazard ratio [HR], 0.93; 95% CI, 0.78 to 1.11; P = .431). As expected, darbepoetin alpha was associated with a higher incidence of thromboembolic events (darbepoetin alpha, 9%; placebo, 5%). The transfusion risk was lower in the darbepoetin versus placebo group (HR, 0.40; 95% CI, 0.29 to 0.55). The results of this study did not demonstrate improved survival after treatment with darbepoetin alpha; however, they reinforce the benefit of erythropoiesis-stimulating agents in reducing transfusions and their neutral impact on survival in patients with chemotherapy-induced anemia.