An eagerly-anticipated two-day hearing into Roche's appeal against the US Food and Drug Administration's proposal to pull Avastin's approval for breast cancer has kicked off at the agency's headquarters in Maryland.

The FDA announced in December that after a review of four clinical studies, it had concluded Avastin (bevacizumab) in combination with paclitaxel neither prolonged overall survival in metastatic breast cancer patients nor provided a sufficient benefit in slowing disease progression. As such, it began the process of removing the breast cancer indication from the drug’s label.

That decision followed a July review by an FDA advisory committee that voted 12-1 to remove the breast cancer indication. Avastin in combination with paclitaxel got the green light in February 2008 under the agency’s accelerated approval programme.

Roche vigorously disagreed with the decision and breast cancer patients have been testifying to an FDA panel. The company, which will be putting its case later today, says that "women with this incurable disease should have the option to choose this medicine".

However, most observers believe that the FDA is unlikely to change its stance, seeing as how especially as five of the six members of the panel also voted against Avastin's use in breast cancer in  July. Indeed, John Jenkins, director of the FDA's Office of New Drugs, told the appeals hearing that "we cannot permit sponsors to evergreen approval of a drug that has not been shown to be safe and effective".

The panel will make its recommendation at the end of the hearing later today and FDA Commissioner Margaret Hamburg is expected to make the final decision.