nanmourinho

ROCKVILLE, Md., Aug. 25, 2008--FDA ALERT [8/2008]: The FDA hasrecently received information from the manufacturer about two newcases of progressive multifocal leukoencephalopathy (PML) inpatients receiving Tysabri monotherapy for multiple sclerosis inEurope. Both patients had received Tysabri for more than one year.PML, which is usually fatal, is a known risk of Tysabri treatment,but previous cases in patients with multiple sclerosis were seen incombination with other immunomodulatory therapies. About 39,000patients have received treatment with Tysabri worldwide, with about12,000 patients having been treated for at least one year. No newcases have been seen in the US, where about 7,500 patients havereceived the drug for longer than one year and about 3,300 patientshave received the drug for at least one and a half years.