Tysabri Withdrawal Clouds Future For Recovering Elan
DUBLIN, Ireland - Confirmation of a second case of progressive multifocal leukoencephalopathy (PML) among the 1,171 multiple sclerosis patients receiving Tysabri (natalizumab) in combination with Avonex (interferon beta-1a) sent shares of Elan Corp. plc and Biogen Idec Inc. further downward last Friday.