Introduction: This study was conducted to establish the maximum tolerated dose (MTD) of intravenous vinorelbine and on the determined dose to assess efficacy and safety in patients with metastatic breast cancer previously treated with epirubicin.
Patients and methods: Patients had histologically proven breast cancer and had received a prior epirubicin based regimen either adjuvant or as first line therapy for advanced disease. Vinorelbine was administered intravenously day 1 and 8 in a 3 weeks' schedule. Subsequently 48 additional patients were treated at one dose-level below MTD.
Results: Fifty-five patients were included in the dose-escalation study, which defined 40 mg/m(2) as the MTD. Neutropenia of short duration and autonomic neuropathy causing constipation were the most common dose-limiting toxicities. At the 35 mg/m(2) dose-level 60 patients were included in total. Seven (12%; 95% CI 6 to 22) had a partial response and 16 additional patients had stable disease. 27% had stable disease (clinical benefit rate 38%, 95% CI 27 to 51). The median overall survival was 45 weeks and 39% of the patients were alive after one year.
Discussion: The clinical benefit rate was 38% with an overall intention to treat response rate of only 12%. The results were, however, achieved with low subjective burdens of toxicity.