BIOGEN ANNOUNCES NEW APPOINTMENTS IN ITS INTERNATIONAL OPERATION

Biogen (NASDAQ/BGEN) today announced several new appointments in its International commercial organization.

Robert A. Hamm has been named Senior Vice President-International, replacing Mark Leuchtenberger, who has announced his intention to resign at the end of this year. Mr. Hamm joined Biogen in 1994 and has played a critical role in building the company’s international commercial structure and operating capability. Most recently, he was Vice President, Sales and Marketing, where he was responsible for reinvigorating the growth rate of AVONEX® (Interferon beta-1a), the company’s flagship product. He has also served as Vice President, Manufacturing, where he led development of Biogen’s global supply chain strategy, and was Biogen’s Director of Northern Europe.

Guy-Charles Fanneau dela Horie has been named Vice President, Strategic Commercial Operations-International. Mr. Fanneau dela Horie joined Biogen in 1995 as country manager responsible for launching AVONEX in France. Most recently, he has been
responsible for several assignments in the U.S., including the positions of National Sales Director and commercial program executive for AVONEX.

Patrick Vink has been appointed Vice President, Sales, responsible for International affiliates. Mr. Vink joined Biogen in 2000 as country manager, Germany.

James C. Mullen, Biogen’s President and Chief Executive Officer, said, “I am delighted that this team is assuming leadership of our European organization. Bob and Guy-Charles were responsible for the repositioning of our U.S. commercial operations, resulting in reinvigoration of the AVONEX market during the past year. They have both worked together before in the European business. Our performance in Europe has been strengthened over the past year, and I am confident that this team will accelerate that trend.”

AVONEX is the world’s leading therapy for the treatment of relapsing forms of multiple sclerosis.

About Biogen
Biogen, Inc., winner of the U.S. National Medal of Technology, is a biopharmaceutical company principally engaged in discovering and developing drugs for human healthcare through genetic engineering. Headquartered in Cambridge, MA, the Company’s revenues are generated from international sales of AVONEX for treatment of relapsing forms of multiple sclerosis, and from the worldwide sales by licensees of a number of products, including alpha interferon and hepatitis B vaccines and diagnostic products. (Please see full prescribing information at http://www.avonex.com) Biogen’s research and development activities are focused on novel products to treat inflammatory and autoimmune diseases, neurological diseases, cancer, fibrosis and congestive heart failure. For copies of press releases and additional information about the Company, please consult Biogen’s Homepage on the World Wide Web at http://www.biogen.com