The US Food and Drug Administration (FDA, Rockville, MD, USA) has announced that bevacizumab (Avastin) is no longer approved for the treatment of breast cancer, but will retain its indications for colon, lung, kidney, and brain cancer.

The FDA oncologic drugs advisory committee had voted unanimously in June 2010 that Avastin, a product of Genentech (San Francisco, CA, USA) and Roche (Basel, Switzerland), should no longer be approved to treat metastatic HER2-negative breast cancer. However, at that meeting, a handful of breast cancer patients known as "super-responders”--women who seem to have responded remarkably well to bevacizumab--begged for continued approval of the drug, noting that their insurance companies are unlikely to pay for the USD 8,000-a-month drug if the FDA strips away the breast cancer indication.

Bevacizumab received accelerated approval for the breast cancer indication in 2008, after a study showed that patients taking the drug had an average 5.5 months more progression-free survival than those treated with paclitaxel alone (11.3 months versus 5.8 months). As a condition of the fast-track approval, Genentech was required to conduct additional clinical trials to prove efficacy and safety. In the follow-on studies, the 5.5 months of progression-free survival seen in the earlier trial nearly disappeared, and no new benefits were observed. But a range of side effects that included severe hypertension, hemorrhage, myocardial infarction (MI), heart failure, and perforations in the nose, stomach, and intestines were made evident.

“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,” said FDA Commissioner Margaret Hamburg, MD. “When the totality of the evidence is examined, there is really not a clear demonstration that the benefits of this drug outweigh the risks.”

Avastin is a humanized monoclonal antibody that inhibits vascular endothelial growth factor A (VEGF-A), thus blocking angiogenesis, the growth of new blood vessels. It is commonly used to treat various cancers, including colorectal, lung, breast, kidney, and glioblastomas. Assuming the FDA follows through on the withdrawal, Genentech and Roche could lose up to USD 1 billion in revenue for the best-selling product, which generates over USD 6 billion per year.

 

Guangzhou Jia Yu medical equipment Limited