(HealthDay News) – For patients with human epidermal growth factor receptor 2 (HER2)-negative breast cancer, the addition of bevacizumab to neoadjuvant chemotherapy improves the pathological complete response (pCR), according to two studies published in the January 26 issue of the New England Journal of Medicine.
Gunter von Minckwitz, MD, from the German Breast Group in Neu-Isenburg, and colleagues investigated the efficacy and safety of adding bevacizumab to neoadjuvant chemotherapy in 1,948 patients with early-stage breast cancer. Participants with untreated HER2-negative breast cancer were randomly allocated to treatment with epirubicin and cyclophosphamide followed by docetaxel, with or without concomitant bevacizumab. The pCR rates were significantly increased with the addition of bevacizumab (18.4% with bevacizumab versus 14.9% without bevacizumab; odds ratio for addition of bevacizumab, 1.29; 95% confidence interval, 1.02 to 1.65; P=0.04). For the 663 patients with triple-negative tumors, the pCR rate was 39.3% with bevacizumab and 27.9% without bevacizumab (P=0.003).
Harry D. Bear, MD, PhD, from the National Surgical Adjuvant Breast and Bowel Project in Pittsburgh, and colleagues investigated the efficacy of adding bevacizumab to neoadjuvant chemotherapy regimens for the treatment of HER2-negative breast cancer. A cohort of 1,206 women was randomly allocated to receive docetaxel, docetaxel plus capecitabine, or docetaxel plus gemcitabine; all regimens were followed by doxorubicin-cyclophosphamide. Patients also were randomly allocated to treatment with or without bevacizumab for the first six cycles of chemotherapy. There was no significant increase in the pCR rate with the addition of capecitabine (29.7%) or gemcitabine (31.8%) to docetaxel therapy compared with docetaxel alone (32.7%; P=0.69). The addition of bevacizumab significantly increased the pCR rate (34.5% with bevacizumab versus 28.2% without bevacizumab; P=0.02).
“The addition of bevacizumab to neoadjuvant chemotherapy significantly increased the rate of pathological complete response,” Bear and colleagues write.
Several authors from the von Minckwitz study disclosed financial ties to pharmaceutical companies, including Sanofi-Aventis and Roche, which funded the study. The Bear study was partially funded by F. Hoffmann-La Roche, Genentech USA, and Eli Lilly.