Biogen Idec Announces Appointment of Nancy L. Leaming to Board of Directors

Biogen Idec (NASDAQ: BIIB) today announced the appointment of
Nancy L. Leaming to its Board of Directors.

"I´m very pleased that Nancy Leaming is joining our Board of
Directors," said Bruce Ross, Biogen Idec´s Chairman. "With extensive
experience in the healthcare sector, Nancy has the proven business and
leadership skills to help Biogen Idec drive our strategic plan forward
in the years ahead."

For twenty years, Leaming, 60, served in several executive
positions at Tufts Health Plan, including President and CEO (2003 -
2005), President and Chief Operating Officer (1997-2003) and Chief
Operating Officer (1986-1997). Leaming successfully led the managed
care company to become a nationally recognized leader in its field,
creating a strategic vision and strong corporate culture defined by
product innovation, service excellence, quality and patient safety.

Leaming has served in various capacities on both commercial and
non-profit boards. She is currently a member of the boards of
directors at Hologic Inc., where she chairs the Audit Committee,
Edgewater Technology Inc., the Massachusetts Taxpayers Foundation and
the American Red Cross of Massachusetts.

About Biogen Idec

Biogen Idec creates new standards of care in therapeutic areas
with high unmet medical needs. Founded in 1978, Biogen Idec is a
global leader in the discovery, development, manufacturing and
commercialization of innovative therapies. Patients in more than 90
countries benefit from Biogen Idec´s significant products that address
diseases such as lymphoma, multiple sclerosis and rheumatoid
arthritis. For product labeling, press releases and additional
information about the company, please visit www.biogenidec.com.