New schedule of bevacizumab/paclitaxel as first-line therapy for metastatic HER2-negative breast cancer in a real-life setting

Angiogenesis plays an essential role in the growth and progression of breast cancer. This observational single center study evaluated the efficacy and safety of a new weekly schedule of bevacizumab/paclitaxel combination in the first-line treatment of unselected, HER2-negative, metastatic breast cancer (MBC) patients, in a real-life setting. Thirty-five patients (median age 56 years, range 40-81) with HER2-negative MBC were treated with paclitaxel (70 mg/m(2) ) dd 1,8,15 q21 (60 mg/m(2) if ≥65 years or secondary Cumulative Illness Rating Scale) plus bevacizumab (10 mg/kg) every 2 weeks. Twenty-two patients (63%) had ≥2 metastatic sites and 15 (43%) visceral disease. Eleven patients (31%) had a triple-negative breast cancer (TNBC). A clinical complete response (cCR) was observed in 6 (17%) cases after a median of seven cycles, a partial response (PR) in 22 (63%), and a stable disease (SD) in 6 (17%) cases; the overall clinical benefit rate was 97%. In TNBC subgroup, cCR occurred in 1 (9%) case, PR in 8 (73%), and SD in 2 (18%). At a median follow-up of 13 months (range 1-79 months), the median progression-free survival was 11 months and the median overall survival was 36 months. No grade 4 adverse events occurred. The main grade 3 toxicities observed were neutropenia (11.4%), hypertension (5.7%), stomatitis (2.8%), diarrhea (2.8%), and vomiting (2.8%). The administration of weekly paclitaxel plus bevacizumab in this real-life experience shows similar efficacy than previously reported schedules, with a comparable dose intensity and a good toxicity profile.