FDA Commissioner Margaret Hamburg held a special press briefing this morning on Genentech’s Avastin drug and its indications for metastatic breast cancer. She announced that the agency is revoking that indication based on FDA follow-up studies which did not show promising results.

Specifically, Hamburg noted that the drug’s benefits for breast cancer patients do not outweigh the drug’s risks to these patients, which can include heart attack, bleeding, and other significant side effects. Studies did not show reduction in tumor size or lengthening of life for breast cancer patients taking the drug. Avastin was approved through FDA’s accelerated pathway in 2008 for this indication. Avastin will continue to hold approval for treating colon, lung, kidney and brain cancer. FDA is not in the practice of medicine, said Hamburg, and recommended that breast cancer patients taking the drug speak with their doctors about potential risks and treatment plans.

Avastin’s breast cancer indication has been in question since June 2011 when an FDA advisory panel recommended removing the approval. Genentech disagreed with the panel, said Hamburg during today’s briefing, and it was ultimately her decision to officially revoke the approval today. Hamburg recommended that the drug sponsor conduct additional studies on the breast cancer indication.