FDA Questions Tysabri for Crohn's Disease

Biogen Idec (BIIB Quote) and Elan (ELN Quote) skidded Friday after a Food and Drug Administration report questioned whether the multiple sclerosis drug Tysabri should be used for treating the chronic gastrointestinal ailment Crohn's disease.

The report by FDA staff members said clinical trials show Tysabri's effect isn't "clearly distinguished" from current therapies. The companies are seeking FDA approval to treat Crohn's disease patients for whom other therapies don't work.

The staff report was issued prior to Tuesday's meeting of outside advisers who will make recommendations to the agency. The FDA isn't required to follow its advisers' suggestions, but it usually does so. Staff reports are routinely issued prior to advisory committee meetings. ...