A decision on whether or not Avastin should be approved to treat breast cancer could come soon from the Food & Drug Administration (FDA). Avastin, is already approved to treat lung and colon cancer, but members of an FDA advisory committee voted 5-4 against approving Avastin for breast cancer treatment in December. However, Genentech recently touted a new Avastin study finished after that vote was taken which showed that Avastin slowed tumor growth in breast cancer patients. Some advocates for breast cancer patients want Avastin approved on that basis alone, while others say the FDA should weigh its serious side effects against its ability to extend the life of people with breast cancer.
Avastin was approved by the FDA in 2004 to treat colon cancer, and in 2006, the agency approved it as a treatment for non-small cell lung cancer. Avastin was the first approved therapy designed to inhibit angiogenesis, the process by which new blood vessels develop and carry vital nutrients to a tumor. Avastin has been a blockbuster for Genentech, and its parent company Roche AG. For the first nine months of 2007, US sales of Avastin topped $1 billion, accounting for 27% of Genentech’s overall product sales. Some analysts believe that if Avastin is approved to treat metastatic cancer – cancer that has spread to other parts of the body – sales of the medication could grow by $1.9 billion by 2009.
But hopes that Avastin could get approval for breast cancer treatment took a hit late last year when the FDA advisory panel voted 5-4 to recommend that the agency reject Genentech’s application to expand the approved uses of the drug to include advanced breast cancer. The FDA advisory panel vote came after agency staffers posted documents on the FDA website noting that while Avastin did extend the period prior to patients’ breast cancer becoming worse, treatment with the drug did not markedly increase survival time. The FDA documents also pointed out that Avastin caused serious side effects, including cardiovascular problems, bowel perforations, and a few deaths. The FDA staff said that those side effects included 5 patient deaths that were “probably or definitely” due to Avastin. While the FDA is not bound by the recommendations of advisory panels, it usually does follow them. For that reason, many were skeptical that Avastin would get approval as a breast cancer treatment.
But some analyst say Avastin’s chances got a boost by a recent press release issued by Genentech that touted a study by Roche. Genentech reported that the Avastin study – which it said was more rigorous than previous studies — found that Avastin slowed the progression of breast cancer. According to The Wall Street Journal, Genentech’s press release offered no data, and the company declined to elaborate pending scientific peer review. So it’s not clear how much the company’s announcement will influence the FDA.
What the FDA must determine is whether to judge Avastin by its ability to slow tumors or its ability to extend survival times of breast cancer patients. On the first point, studies have indicated that Avastin slows cancer, but it doesn’t appear to extend the life of breast cancer patients. But some advocates for breast cancer patients are pushing for the FDA to approve Avastin anyway, because slowing tumor growth can lead to a higher quality of life for many.