Weekly combination of docetaxel and vinorelbine in metastatic breast cancer: a phase I/II study.

Objective: A phase I/II study was carried out to determine the recommended dose (RD) and to assess the efficacy and safety of a weekly docetaxel-vinorelbine combination in advanced breast cancer (ABC) patients.

Methods: Twenty-four female patients with histologically proven ABC received intravenous vinorelbine (20 min) followed by intravenous docetaxel (1 h) on days 1, 8 and 15 of a 4-week cycle. Starting doses were 20 mg/m2 docetaxel and 15 mg/m2 vinorelbine.

Results: Patients had a median age of 62 years (range 38-74 years), and 92% had performance status 0-1. The most common sites of metastases were the lungs (32%), liver (29%) and bone (14%). Seventy-one percent of patients had received prior chemotherapy. The RDs of docetaxel and vinorelbine were 20 and 15 mg/m2, respectively. Dose-limiting toxicities were neutropenia-induced dose delay and febrile neutropenia. The response rate at the RD was 43%. All responses were seen in non-pretreated patients. Grade 3-4 neutropenia occurred in 80% of patients, 3 of whom experienced febrile neutropenia and died as a possible consequence of neutropenia.

Conclusion: This docetaxel-vinorelbine combination as first-line therapy yields a response rate similar to that of single-agent docetaxel as second-line therapy. However, given the high rate of myelotoxicity, higher doses are not feasible.