Tysabri 2-Year MS Study: The Battle Is Joined

April 13, 2005 Researchers presented data from a two-year study of Tysabri, the currently withdrawn MS drug from Biogen Idec and Elan showing that the drug clearly lessens the devastating impact of multiple sclerosis. The drug is effective. But it also, in rare cases, can cause death. Is there any way the drug can come back on the market?