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)

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/m(2) on day 1 and vinorelbine 25 mg/m(2) on days 1 and 8, or epirubicin 90 mg/m(2) 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 1000 mg/m(2) (950 mg/m(2) 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.