Improved Pathologic Complete Response Rate With Addition of Bevacizumab to Neoadjuvant Therapy in HER2-Negative Early Breast Cancer
In the phase III ARTemis trial reported in The Lancet Oncology, Earl et al found that the addition of bevacizumab (Avastin) to standard neoadjuvant therapy resulted in a higher pathologic complete response rate in women with HER2-negative early breast cancer.
Study Details
In this open-label trial, 800 women with newly diagnosed invasive disease were randomly assigned between May 2009 and January 2013 to four cycles of bevacizumab at 15 mg/kg with (n = 399) or without (n = 401) three cycles of docetaxel at 100 mg/m2 once every 21 days followed by three cycles of fluorouracil at 500 mg/m2, epirubicin at 100 mg/m2, and cyclophosphamide at 500 mg/m2 once every 21 days (D-FEC). The primary endpoint was pathologic complete response.
Response Rates
Among 781 evaluable patients, pathologic complete response was observed in 22% (95% confidence interval [CI] = 18%–27%) of 388 patients in the bevacizumab plus D-FEC group compared with 17% (95% CI = 13%–21%) of 393 patients in the D-FEC group (P = .03). Complete response rates were higher with bevacizumab among the 241 patients with estrogen receptor–negative disease (45% vs 31%) and 74 patients with estrogen receptor–weakly positive disease (51% vs 30%).
Adverse Events
Grade 3 or 4 infection occurred in 20% (18% grade 3) of the bevacizumab group vs 11% (10% grade 3) in the D-FEC group. Grade 4 neutropenia occurred in 22% vs 17%. A total of 265 serious adverse events were reported in the bevacizumab group, and 196 were reported in the D-FEC group.
The investigators concluded: “Addition of four cycles of bevacizumab to D-FEC in HER2-negative early breast cancer significantly improved pathological complete response. However, whether the improvement in pathological complete response will lead to improved disease-free and overall survival outcomes is unknown and will be reported after longer follow-up. Meta-analysis of available neoadjuvant trials is likely to be the only way to define subgroups of early breast cancer that would have clinically significant long-term benefit from bevacizumab treatment.”
Helena M. Earl, MBBS, of University of Cambridge, is the corresponding author for The Lancet Oncology article.
The study was funded by Cancer Research UK, Roche, and Sanofi-Aventis. For full disclosures of the study authors, visit www.thelancet.com.
The content in this post has not been reviewed by the American Society of Clinical Oncology, Inc. (ASCO®) and does not necessarily reflect the ideas and opinions of ASCO®.
