Phase III Study of Intravenous Vinorelbine in Combination With Epirubicin Versus Epirubicin Alone in Patients With Advanced Breast Cancer: A Scandinavian Breast Group Trial (SBG9403)

Abstract

Purpose To determine whether the addition of intravenous (IV) vinorelbine to epirubicin increased the progression-free survival in first-line treatment of metastatic breast cancer. Patients and Methods A total of 387 patients were randomly assigned to receive IV epirubicin 90 mg/m2 on day 1 and vinorelbine 25 mg/m2 on days 1 and 8, or epirubicin 90 mg/m2 IV on day 1. Both regimens were given every 3 weeks for a maximum of 1 year but discontinued prematurely in the event of progressive disease or severe toxicity. In addition, epirubicin was discontinued at a cumulative dose of 1,000 mg/m2 (950 mg/m2 from June 1999). Prior anthracycline-based adjuvant chemotherapy and prior chemotherapy for metastatic breast cancer was not allowed. Reported results were all based on intent-to-treat analyses. Results Overall response rates to vinorelbine and epirubicin, and epirubicin alone, were 50% and 42%, respectively (P = .15). The complete response rate was significantly superior in the combination arm (17% v 10%; P = .048) as was median duration of progression-free survival (10.1 months v 8.2 months; P = .019). Median survival was similar in the two arms (19.1 months v 18.0 months; P = .50). Leukopenia related complications, stomatitis, and peripheral neuropathy were more common in the combination arm. The incidences of cardiotoxicity and constipation were similar in both arms. Conclusion Addition of vinorelbine to epirubicin conferred a significant advantage in terms of complete response rate and progression-free survival, but not in terms of survival.