A Study to Evaluate the Efficacy and Safety of Oral Navelbine in Female Patients With HER2-Negative Metastatic Breast Cancer

1. The significant efficacy and good safety profile of Vinorelbine in the treatment of advanced breast cancer are accepted. 2. Oral NVB presents absolute bioavailability of 40% and oral availability allows to use different schedules and the endothelial cell functionality and motility are interfered at very low drug concentration 3. Oral NVB at 50 mg three times a week (Monday-Wednesday-Friday) has been tested in phase Ia/Ib/II trials, highlighting the excellent safety of this scheme combined with an interesting activity in various European countries. 4. The study aims to evaluate the efficacy and safety of metronomic chemotherapy with oral Navelbine versus intermittent oral Navelbine in female patients with HER2 negative Metastasis Breast Cancer.