Elan: No new PML cases in Tysabri evaluation

Pharmaceutical company Elan has said a safety evaluation of multiple sclerosis (MS) and Crohn's disease drug Tysabri in MS patients resulted in no new confirmed cases of potentially fatal progressive multifocal leukoencephalopathy (PML).

More than 2,000 MS patients from clinical trials were eligible for the safety evaluation. To date, 91% of these MS patients participated in the safety evaluation. The remaining 9% of patients did not participate in the safety review.

Elan and fellow pharmaceutical company Biogen had previously reported three confirmed cases of PML, two of which were fatal.

On February 28 this year, Biogen and Elan announced a voluntary suspension of Tysabri from the US market and all ongoing clinical trials based on reports of PML, a rare and potentially fatal, demyelinating disease of the central nervous system. Biogen Idec and Elan's safety evaluation concerning Tysabri and any possible link to PML is ongoing.

The on-going safety evaluation in Crohn's disease and rheumatoid arthritis is on track to be completed by the end of the summer, Elan said today.

The companies anticipate making submissions to regulatory authorities within weeks and are taking preliminary steps to restart clinical trials in MS.