Washington Editor

The FDA Monday approved Tysabri (natalizumab) for use in patients with moderate to severe Crohn's disease.

Tysabri, marketed by Cambridge, Mass.-based Biogen Idec and Dublin, Ireland-based Elan Corp., already is approved in the U.S. for use in patients with multiple sclerosis.

However, the drug was pulled temporarily from the market in 2005 in response to concerns about three cases of progressive multifocal leukoencephalopathy (PML), a rare neurologic disorder, that had been linked to the drug.

The FDA a year later approved the drug's return to the market under a stringent restricted distribution program for patients with relapsing forms of multiple sclerosis.

In a 12 to 3 vote, an FDA advisory committee in July recommended that Tysabri could be used safely in patients with Crohn's disease.

Joyce Korvick, deputy director of the FDA's Division of Gastroenterology Products, noted that the approval for the Crohn's disease indication is for inducing and maintaining clinical response and remission in adult patients with moderately to severely active disease with evidence of inflammation who have had an inadequate response to or are unable to tolerate conventional therapies.

Patients using the drug must be enrolled in a restricted distribution program similar to the one designed for patients with multiple sclerosis, Korvick told reporters Monday during a telebriefing.

Crohn's disease, a chronic and progressive inflammatory disease of the gastrointestinal tract, affects about 500,000 men and women in the U.S.

"There is no cure," Korvick noted.

"We are delighted that Tysabri will be available for Crohn's patients and their physicians, who continue to need new therapeutic options with novel mechanisms of action, Gordon Francis, Elan's senior vice president of global clinical development, said in a statement.

Shares of Biogen Idec (NASDAQ:BIIB) rose 96 cents Monday, to close at $59.98. Shares of Elan (NYSE:ELN) rose 13 cents to close at $24.89.