The approval of bevacizumab, the angiogenesis inhibitor marketed as Avastin, as a treatment for metastatic breast cancer is being withdrawn by the Food and Drug Administration, the agency announced Nov. 18.
In the statement announcing the decision, FDA commissioner Dr. Margaret Hamburg said she is revoking the approval, because the use of Avastin as a first-line treatment for metastatic breast cancer has not been shown to be safe and effective. Avastin is approved for several other types of cancers, so it will remain on the U.S. market.
The FDA granted an accelerated approval to bevacizumab in combination with paclitaxel as a first-line treatment for metastatic breast cancer in February 2008, based on an open-label study that found a survival advantage for the combined treatment, compared with treatment with paclitaxel alone. Studies confirming the beneficial effects are a condition of accelerated approvals. In this case, though, follow-up studies failed to confirm the benefit, and the FDA decided to withdraw its approval of the breast cancer indication
In an unusual move, the manufacturer, Genentech, requested a hearing on the decision, which was held in July 2011. At that meeting, the Oncologic Drugs Advisory Committee unanimously voted that approval for the breast cancer indication should be withdrawn because clinical trials did not show an improvement in overall survival or any clinically meaningful improvements in progression-free survival. The final decision was left to Dr. Hamburg.
"This was a difficult decision. FDA recognizes how hard it is for patients and their families to cope with metastatic breast cancer and how great a need there is for more effective treatments. But patients must have confidence that the drugs they take are both safe and effective for their intended use," Dr. Hamburg said in the statement. "After reviewing the available studies, it is clear that women who take Avastin for metastatic breast cancer risk potentially life-threatening side effects without proof that the use of Avastin will provide a benefit, in terms of delay in tumor growth, that would justify those risks. Nor is there evidence that use of Avastin will either help them live longer or improve their quality of life." Her decision is explained in a 69-page opinion.
A statement issued by Genentech immediately after the FDA statement was released said that the company was disappointed with the outcome, remained committed to women with the disease, and would "continue to provide help through our patient support programs to those who may be facing obstacles to receiving their treatment." Despite the FDA’s decision, the company said it planned to start a new phase III study of Avastin in combination with paclitaxel in women with previously untreated metastatic breast cancer, which would "evaluate a potential biomarker that may help identify which people might derive a more substantial benefit from Avastin."
In the FDA statement, Dr. Hamburg said that she encouraged Genentech to consider other studies "to identify if there are select subgroups of women suffering from breast cancer who might benefit from this drug."
At least for now, Medicare coverage of bevacizumab will continue for women with breast cancer. A statement issued by the Centers for Medicare & Medicaid Services said that the agency would “monitor the issue and evaluate coverage options as a result of action by the FDA but has no immediate plans to change coverage policies.”
Avastin is still approved for treating metastatic breast cancer in more than 80 countries.
This story was updated November 18, 2011.