Bevacizumab (Avastin) improved progression-free survival (PFS) in patients with ovarian cancer but was not shown to affect overall survival (OS), according to a new study published in the New England Journal of Medicine
In the double-blind, placebo-controlled phase III study, 1873 patients with previously untreated advanced-stage ovarian cancer were separated into 3 study arms. One arm received bevacizumab with chemotherapy (intravenous paclitaxel plus carboplatin), followed by bevacizumab for up to 10 months. Another arm received the same chemotherapy but were given a placebo instead of bevacizumab, while a third arm received bevacizumab with chemotherapy but did not receive bevacizumab after the initial treatment.
The median PFS was 14.1 months (hazard ratio [HR] = 0.717; 95% CI, 0.625-0.824; P
<.001) with bevacizumab throughout, as compared with 11.2 months (HR = 0.908; 95% CI, 0.795-1.040; P
= .16) in the bevacizumab initiation group and 10.3 months in the control arm. At the time of the analysis, 76.3% of patients were still alive, but the authors reported no significant differences in OS among the 3 groups.
“This approach can be looked upon as a third major component of treatment for ovarian cancer and related malignancies,” said Robert A. Burger, MD, lead investigator on the Gynecologic Oncology Group study and director of the Women’s Cancer Center at Fox Chase Cancer Center, in a statement. “We’ve had the combination of surgical management and cytotoxic chemotherapy for many years, but we haven’t really seen anything else in terms of a fundamental class of treatment. This represents a new way for us to control the disease.”
Hypertension was the most prominent side effect associated with bevacizumab, with 22.9% of patients in the bevacizumab-throughout group and 16.5% of patients in the bevacizumab-initiation group requiring medical therapy to manage the side effect, compared to 7.2% in the control group.
While bevacizumab is already approved by the FDA for use in certain types of brain, colon, kidney, and lung cancers, the drug has not yet gained approval for treating patients with ovarian cancer in the United States. The European Commission, however, recently approved the drug for women newly diagnosed with late-stage ovarian cancer.
The National Cancer Institute estimates that nearly 22,000 women were diagnosed with ovarian cancer in 2011, with approximately 15,000 patients dying of the disease.