Avastin Not Good for Breast Cancer, FDA Panel Says

The FDA may soon reconsider the drug's use in advanced breast cancer.

July 20, 2010— -- GAITHERSBURG, Md. -- An advisory panel has voted 12 to 1 to recommend that the U.S. Food and Drug Administration revoke their approval of the blockbuster cancer drug Avastin -- known generically as bevacizumab -- for the treatment of advanced breast cancer.

The decision follows the results of two large clinical trials which failed to demonstrate a clinically meaningful benefit of the drug, which carries serious side effects.

The Oncologic Drugs Advisory Committee voted that Avastin -- when added to standard chemotherapy -- does not keep cancer from worsening for a long enough time to be clinically meaningful to HER2-negative, metastatic breast cancer. The panel voted that the FDA should revoke approval for Avastin manufacturer Genentech to market the drug for breast cancer.

If the FDA followed the advice of its advisory committee -- and it often does -- Avastin would still be approved to treat lung, kidney, and colon cancer. The agency will make a decision on whether to revoke approval for the drug by Sept. 17.

The FDA granted special, fast-track approval to Avastin manufacturer Genentech in 2008 to being marketing the drug for patients with metastatic breast cancer in combination with chemotherapy agent paclitaxel. The "accelerated" approval was based on positive early findings from a large clinical trial sponsored by the company.

But the two clinical trials of nearly 2,000 breast cancer patients that Genentech submitted to move from accelerated approval to standard approval failed to confirm the magnitude of progression-free survival seen in the earlier study, FDA reviewers and the panel concluded.

The panel voted unanimously -- 12 to 0 -- that the two new trials, taken together, failed to demonstrate enough benefit to using Avastin to warrant the drugs' risks, which include serious adverse events, including a small risk of death, as well as other side effects such as bleeding and hypertension.

"We have definitive evidence that Avastin causes serious and life-threatening side effects," said panel chairman Dr. Wyndham Wilson, chief of the lymphoma section at the National Institutes of Health. "We've seen another studies that show no overall improve in quality of lives people have ... and there hasn't been evidence shown that it has led to clinical benefit."

Genentech Stands By Avastin for Breast Cancer

Moreover, the results suggested to researchers that those taking the drug survived no longer than those who did not.

"Survival trumps everything, and we haven't shown a survival benefit here," said Dr. Ronald Richardson, a medical oncologist at the Mayo Clinic.

Genentech argued that even small gains in progression-free survival are clinically meaningful and that additional weeks where tumors don't worsen translate to improved quality of life. The committee was skeptical of that claim.

"We stand by the data we presented today on Avastin in advanced breast cancer, and believe Avastin should be an option for patients with this incurable disease," the company said in a release.

Avastin also is also used treat recurrent glioblastoma under accelerated approval.