Tysabri Still Holding Strong

I’m happy to report that Tysabri is still showing a 67% reduction in relapse rates in patients taking it for a third year and has caused no new cases of progressive multifocal leukoencephalopathy (PML) in people with MS. This data was presented at the annual meeting of the American Academy of Neurology and was the first safety update since it came back in July 2006.

Tysabri is one of the disease-modifying therapies that are currently available. Its manufacturer, Biogen, withdrew Tysabri in February 2005 after two patients in clinical trials died from PML. Last June, the FDA approved Tysabri under the condition that any patients taking the drug register with a program designed to ensure its safe use.

Currently, about 10,000 people worldwide are taking Tysabri through prescription or as part of a clinical trial. While the recent safety update and data on sustained effectiveness is obviously great news, some experts say that many docs will probably wait another year or two before prescribing the drug.