Biogen Idec Announces Management Change

CAMBRIDGE, Mass.--(BUSINESS WIRE)--March 9, 2005--Biogen Idec Inc. (NASDAQ: BIIB) announced today that Thomas Bucknum, Executive Vice President and General Counsel, has resigned from the company. The resignation is effective immediately.

About Biogen Idec

Biogen Idec creates new standards of care in oncology and immunology. As a global leader in the development, manufacturing, and commercialization of novel therapies, Biogen Idec transforms scientific discoveries into advances in human healthcare. For product labeling, press releases and additional information about the company, please visit www.biogenidec.com

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