March 9, 2006

An FDA advisory panel has recommended that Biogen Idec and Elan's multiple sclerosis (MS) drug Tysabri return to the market under certain conditions.

The FDA's Peripheral and Central Nervous System Drugs Advisory Committee has voted unanimously to return Tysabri (natalizumab) to the market. The advisers also recommended Biogen establish a mandatory patient registry to monitor side effects. In addition, the panel voted 7-5 in favor of allowing Tysabri on the market as a first-line treatment.

FDA reviewers earlier had suggested various restrictions if the product were allowed back on the market, including limiting prescribing and dispensing to selected prescribers and pharmacists.

The panel's decision comes after the firms voluntarily withdrew Tysabri in February 2005 following reports that three patients taking the drug had developed progressive multifocal leukoencephalopathy, a rare and deadly nerve disease.

Biogen Idec and Elan were "pleased with the vote," said Amy Ryan, a spokeswoman for Biogen Idec. The firms consider the recommendation "a positive step forward, but just one of the steps," she said, noting the agency still must agree to the recommendation. The FDA is required to render a decision on the drug by the end of the month, Ryan added. While the agency is not bound by advisory board decisions, the FDA usually follows a board's advice.

Tysabri, which was approved in November 2004 as a treatment for relapsing forms of MS, is considered to be one of the companies' most promising products. The drug will likely produce $1 billion in sales in 2009, said Alexander Hittle, an analyst with A.G. Edwards & Sons.

One observer says the advisory panel's recommendation on the drug may signify the FDA's willingness to change its stance on drug recalls. This decision may represent a change in agency policy toward recalls, said Dan Troy, a partner at Sidley Austin in Washington, D.C., and a former chief counsel for the agency.

"I hope that it's a sign that some rationality is returning to the process," he told FDAnews. Since the controversy over the agency's handling of Vioxx, the FDA has been too quick to pull drugs from the market upon finding evidence of adverse events, critics have said. (http://www.fdanews.com/did)