The USA’s Biogen Idec and its Irish partner Elan Corp say that a date has been set for a review of the firms’ Tysabri as a treatment for Crohn's disease.

The companies said Tysabri (natalizumab) would be jointly reviewed by the US Food and Drug Administration's Gastrointestinal Drugs Advisory Committee and Drug Safety and Risk Management Advisory Committee on July 31 and if it gets a positive recommendation, that would complete quite a turnaround in fortunes.

The drug only returned to the market as a multiple sclerosis treatment in July after being pulled off on safety concerns in February 2005, and its reintroduction came with restrictions to monitor patients for symptoms of the rare brain disease PML (progressive multifocal leukoencephalopathy). However nearly 10,000 people have been prescribed with the drug and the company is confident that Tysabri will continue to penetrate the MS market.

Getting a green light for Crohn’s disease would do no harm to sales for the humanised monoclonal antibody which is believed to block entry of inflammatory immune cells into the wall of the intestine, thus limiting inflammatory damage in Crohn's disease.