Biogen Idec, Inc. (Massachusetts) And Elan Pharmaceuticals Announce That FDA Will Extend Regulatory Review Period For The Reintroduction Of TYSABRI(R) For Multiple Sclerosis

CAMBRIDGE, Mass. & DUBLIN, Ireland--(BUSINESS WIRE)--March 22, 2006--Biogen Idec (NASDAQ: BIIB) and Elan Corporation, plc. (NYSE: ELN) announced today that the U.S. Food and Drug Administration (FDA) informed the companies that the Agency will extend its regulatory review of TYSABRI(R) (natalizumab) as a treatment for multiple sclerosis by up to 90 days.