The role of bevacizumab has been among the more contentious issues in breast cancer oncology of late. At the San Antonio Breast Cancer Symposium, investigators will add results from two more trials – the BEATRICE and LEA studies – to the ongoing debate.
BEATRICE Targets Early Triple-Negative Disease
Patients had to have confirmed triple-negative disease to be enrolled in the multinational, randomized, open-label BEATRICE study sponsored by Hoffman-La Roche, which markets bevacizumab (Avastin) in Europe.
Their tumors had to be operable primary invasive breast cancer, for which the patients completed definitive locoregional surgery. Those with locally advanced breast cancer were excluded from BEATRICE, which had a target enrollment of more than 2,500 patients.
The underlying question is whether adding 1 year of bevacizumab to standard adjuvant therapy is safe and can improve efficacy. Invasive disease–free survival is the primary outcome measure of BEATRICE, which began recruitment in 2007. "Primary" results are slated for presentation in General Session 6 at the San Antonio meeting (S6-5). Investigators also have prepared a biomarker analysis (Poster session 3, P3-06-34).
LEA Focuses on Advanced Hormone Receptor–Positive Disease
The first efficacy results from the phase III LEA study will focus on the addition of bevacizumab to first-line endocrine treatment in women who are eligible for hormonal therapy and also HER2 negative.
The Spanish Breast Cancer Research Group sponsored the trial in collaboration with the German Breast Group and Hoffmann-La Roche. It was designed to test the hypothesis that targeting the vascular endothelial growth factor (VEGF) with bevacizumab could present resistance to endocrine therapy "in patients with advanced breast cancer sensitive to such treatment" (Cancer Res. 2011;71(24 Supplement):OT3-01-15 [doi: 10.1158/0008-5472.SABCS11-OT3-01-15]).
The protocol called for enrollment of 378 patients with locally advanced or metastatic breast cancer. All received endocrine therapy with letrozole (Femara) or fulvestrant (Faslodex) during the trial; the experimental arm also received bevacizumab, and patients could continue on bevacizumab if they had not progressed on study.
Two-year progression-free survival is the primary end point of the trial, which began recruitment in November 2007. The first efficacy results will be presented in San Antonio (General session 1, S1-7).
Ongoing Quest to Define Who Would Benefit
Just over a year ago, on Nov. 18, 2011, Food and Drug Administration (FDA) Commissioner Margaret Hamburg announced her decision to revoke an indication for bevacizumab in combination with paclitaxel for metastatic breast cancer. She acted after an emotional public hearing at which women with stage IV disease testified that they benefited from bevacizumab.