健康英语新闻:U.S. FDA revokes approval of Avastin for breast cancer

WASHINGTON, Nov. 18 (Xinhua) -- The U.S. Food and Drug Administration (FDA) on Friday revoked its approval of Avastin for treating the breast cancer after concluding that the drug has not been shown to be safe and effective for that use.

Avastin will still remain on the market as an approved treatment for certain types of colon, lung, kidney and brain cancer.

"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," FDA Commissioner Margaret Hamburg said in a statement. "Nor is there evidence that use of Avastin will either help them live longer or improve their quality of life. "

Avastin's risks include severe high blood pressure; bleeding and hemorrhaging; heart attack or heart failure; and the development of perforations in different parts of the body such as the nose, stomach, and intestines.

Avastin was approved for metastatic breast cancer in February 2008 under the FDA's accelerated approval program, which allows a drug to be approved based on data that are not sufficiently complete to permit full approval. After the approval, the drug's sponsor, Genentech, completed two additional clinical trials and submitted the data from those studies to the FDA. These data showed only a small effect on tumor growth without evidence that patients lived any longer or had a better quality of life compared to taking standard chemotherapy alone -- not enough to outweigh the risk of taking the drug.

FDA's Center for Drug Evaluation and Research, which is responsible for the approval of this drug, ultimately concluded that the results of these additional studies did not justify continued approval and notified Genentech it was proposing to withdraw approval of the indication.

Genentech did not agree with the Center's evaluation of the data and, following the procedures set out in FDA regulations, requested a hearing on the Center's withdrawal proposal, with a decision to be made by the Commissioner. That two-day hearing, which took place June 28-29, included recommendations from the FDA 's Oncologic Drugs Advisory Committee, voting 6-0 in favor of withdrawing approval of Avastin's breast cancer indication.