Purpose: Continuous administration of oral vinorelbine, given 3 times a week (metronomic), is feasible and exceptionally well tolerated at doses up to 50 mg with clinical activity against refractory tumors. In this phase II study oral metronomic vinorelbine and bevacizumab were evaluated as salvage therapy in women with pretreated metastatic breast cancer (MBC).
Methods: Patients received oral vinorelbine (50 mg 3 times a week) and bevacizumab (10 mg/kg) biweekly in cycles of 28 days. The primary endpoint was objective response rate (ORR). A preplanned analysis was performed when the first 13 patients were evaluated for tumor response.
Results: One patient (7.7%) achieved partial response (PR) and 6 (46.1%) stable disease (SD). The combination was very well tolerated but, as per protocol, the study was closed prematurely due to lack of efficacy.
Conclusion: The combination of oral metronomic vinorelbine and bevacizumab has good tolerance but minimal activity in terms of objective responses in pretreated patients with MBC.