I hope breast cancer is the next big cancer for bavituximab.
From Cancer Discovery News Dec 13, 2012.
Bevacizumab Fails to Up Breast Cancer Survival
The antiangiogenic agent bevacizumab (Avastin; Genentech) did not produce statistically significant improvements in survival in 2 randomized phase III clinical trials, one for patients with triple-negative breast cancer and one for patients with HER2-negative, hormone receptor (HR) –positive breast cancer, reported at the San Antonio Breast Cancer Symposium on December 7.
In the BEATRICE study, 2,591 patients with primary triple-negative breast cancer were randomly assigned to receive either adjuvant chemotherapy or chemotherapy plus a year of bevacizumab treatment. The 2 groups showed no statistically significant differences in invasive disease–free survival (the primary endpoint) or in interim overall survival.
“Sadly, for these patients, we have nothing extra to add to chemotherapy,” said lead author David Cameron, MD, professor of oncology at Edinburgh University in Scotland.
“It's getting to be difficult to know the role of bevacizumab, if any, in breast cancer,” commented Kent Osborne, MD, director of the Dan L. Duncan Cancer Center in Houston, TX, who was not involved in the study. “If it's going to work, you'd think it would work in this case,” by suppressing growth of vasculature for emerging metastatic tumors.
Results also were discouraging in the LEA trial, in which 380 postmenopausal women with advanced HER2-negative, HR-positive breast cancer were given first-line therapy of either letrozole (Femara; Novartis) or fulvestrant (Faslodex; AstraZeneca), or one of those drugs combined with bevacizumab.
It was hoped that bevacizumab would be helpful in dealing with high VEGF levels associated with decreased response to endocrine therapy, said lead author Miguel Martin, PhD, of the Instituto de Investigación Sanitaria Gregorio Marañón in Madrid, Spain. “Unfortunately, the LEA study fails to demonstrate a statistically significant improvement in progression-free survival (PFS) for endocrine therapy and bevacizumab.”
The median PFS was 18.4 months for the group taking bevacizumab versus 13.8 months for the control group, and overall survival rates have been essentially identical to date.
LEA drew much attention as the first study to report on combining bevacizumab with endocrine therapy rather than chemotherapy, noted Peter Ravdin, MD, PhD, director of the Breast Health Clinic at the Cancer Therapy and Research Center at the University of Texas Health Science Center in San Antonio, who was not involved in the work.
“This study is part of a general disappointment about bevacizumab in breast cancer,” Ravdin said. “There are people who definitely benefit by this drug, but we don't have a good biomarker to identify them. Bevacizumab also has toxicity and it's fearsomely expensive.”
Overall, in breast cancer treatment, “this drug has activity, but in an unselected base of patients, it often doesn't have enough activity to have a big hit,” remarked Edinburgh's Cameron. “It's an open question whether, in the subgroups that show more activity, bevacizumab has enough activity to become firmly established.”
