William H. Rastetter, Ph.D., Executive Chairman of Biogen Idec

William H. Rastetter, Ph.D., was formerly Chairman and Chief Executive Officer of IDEC. Dr. Rastetter was appointed Chairman of the Board of Directors of IDEC on May 22, 1996. He served as President and Chief Executive Officer of IDEC from December 1986 until January 2002. Dr. Rastetter was also Chief Financial Officer of IDEC from 1988 to 1993. From 1984 to 1986, Dr. Rastetter was Director of Corporate Ventures at Genentech. From 1982 to 1984, he served in a scientific capacity at Genentech, directing the Biocatalysis and Chemical Sciences groups. From 1975 to 1982, Dr. Rastetter held various positions at the Massachusetts Institute of Technology. He received his S.B. in Chemistry from the Massachusetts Institute of Technology and his M.A. and Ph.D. in Chemistry from Harvard University.

Dr. Rastetter has served as a Director of IDEC since 1986. In addition to his positions at Biogen Idec, Dr. Rastetter serves as a Director on the board of Illumina, Inc., a company that develops parallel, miniaturized and flexible biosensors. He also serves on the California Healthcare Institute (CHI). In addition, he is the R.B. Woodward Visiting Scholar of the Department of Chemistry and Chemical Biology at Harvard University.

James C. Mullen, Chief Executive Officer of Biogen Idec

James C. Mullen was formerly Chairman of the Board and Chief Executive Officer of Biogen. He was named Chairman of the Board of Directors of Biogen in July 2002, after being named President and Chief Executive Officer of Biogen in June 2000. Mr. Mullen joined Biogen in 1989 as Director, Facilities and Engineering. He was named Vice President, Operations, in 1992. From 1996 to 1999, Mr. Mullen served as Vice President, International, with responsibility for building all Biogen operations outside North America.

From 1984 to 1988, Mr. Mullen held various positions at SmithKline Beckman Corporation (now GlaxoSmithKline plc). He holds a B.S. in Chemical Engineering from Rensselaer Polytechnic Institute and a M.B.A. from Villanova University.

Mr. Mullen has served as a Director of Biogen since 1999. Mr. Mullen also serves on the Board of Trustees of Rensselaer Polytechnic Institute, the Board of Directors of the Biotechnology Industry Organization (BIO) and is co-chair of Cambridge Family and Children’s Service Capital Campaign Steering Committee.

Alan Belzer, Director

Alan Belzer was President, Chief Operating Officer and Director of Allied-Signal, Inc. (now Honeywell International Inc.) from 1988 until his retirement in 1993. From 1983 to 1988, Mr. Belzer was Executive Vice President and President of Engineered Materials Sector of Allied-Signal, Inc.

Mr. Belzer began serving as a Director of Biogen in 1990.

Lawrence C. Best, Director

Lawrence C. Best is Senior Vice President and Chief Financial Officer of Boston Scientific Corporation and has held those positions since 1992. From 1981 to 1992, Mr. Best served as Senior Partner with Ernst & Young. From 1979 to 1981, Mr. Best served as a Professional Accounting Fellow in the Office of the Chief Accountant at the Securities and Exchange Commission.

Mr. Best began serving as a Director of Biogen in 2003.

Alan B. Glassberg, M.D., Director

Alan B. Glassberg, M.D., is Associate Director of Clinical Care and Director of General Oncology at the University of California San Francisco Cancer Center, and also serves as Director of Hematology and Medical Oncology at Mount Zion Medical Center in San Francisco, California. Dr. Glassberg has been associated with the University of California, San Francisco since 1970 and is currently a Clinical Professor of Medicine. He received his M.D. from the Medical University of South Carolina in Charleston.

Dr. Glassberg began serving as a Director of IDEC in 1997.

Mary L. Good, Ph.D., Director

Mary L. Good, Ph.D., is Managing Member, Venture Capital Investors, LLC and has served in that position since 1997. Dr. Good is also Donaghey University Professor and Dean, Donaghey College of Information Science and System Engineering at University of Arkansas at Little Rock, a position she has held since 1998. From 1993 to 1997, she served as Under Secretary for Technology, United States Department of Commerce. From 1988 to 1993, Dr. Good served as Senior Vice President, Technology of Allied-Signal, Inc. (now Honeywell International Inc.).

Dr. Good began serving as a Director of Biogen in 1997. She is also a Director of IDEXX Laboratories, Inc. and Delta Bank and Trust.

Thomas F. Keller, Ph.D., Director

Thomas F. Keller, Ph.D. is R.J. Reynolds Professor of Business Administration, Duke University, and has served in that position since 1974. From 1999 to 2001, Mr. Keller served as Dean of the Fuqua School of Business Europe at Duke University. From 1974 to 1996, Mr. Keller served as Dean of the Fuqua School of Business at Duke University.

Mr. Keller began serving as a Director of Biogen in 1996. He is also a Director of Dimon, Inc., Wendy’s International, and Nations Funds.

Robert W. Pangia, Director

Robert W. Pangia has worked in investment banking for 20 years and is currently a partner in Ivy Capital Partners, LLC, the general partner of Ivy Healthcare Capital, L.P., a private equity fund specializing in healthcare investments. From 1996 to February 2003 Mr. Pangia was self-employed as an investment banker. From 1987 to 1996 Mr. Pangia held various senior management positions at PaineWebber including: member of the board of directors of PaineWebber, Inc., Chairman of the board of directors of PaineWebber Properties, Inc., member of PaineWebber’s executive and operating committees, Chairman of the equity commitment committee, member of the debt commitment committee and Executive Vice President and Director of Investment Banking for PaineWebber Incorporated of New York. Prior to his positions at PaineWebber, Mr. Pangia held other senior positions including Managing Director of Investment Banking for Drexel Burnham Lambert of New York and Vice President of Investment Banking for Kidder, Peabody & Co. of New York. He received his A.B. from Brown University and his M.B.A. from Columbia University.

Mr. Pangia began serving as a Director of IDEC in September 1997. He is also a Director of ICOS Corporation and Network Associates, Inc.

Bruce R. Ross, Director

Bruce R. Ross is currently President of Cancer Rx, a healthcare consulting firm. Immediately prior to launching Cancer Rx, Mr. Ross was Chief Executive Officer of the National Comprehensive Cancer Network, an association of fifteen of the largest cancer centers in the United States. He previously held senior management positions, during a 27-year career, at Bristol-Myers Squibb, including Senior Vice President, Policy, Planning and Development, Bristol-Myers Squibb Pharmaceutical Group and President, Bristol-Myers Squibb U.S. Pharmaceutical Group. He received his B.S. from Syracuse University and later was a Bristol-Myers Scholar at the Yale School of Organization and Management.

Mr. Ross began serving as a Director of IDEC in 1997.

The Honorable Lynn Schenk, Director

Lynn Schenk was appointed as Chief of Staff to the Governor of California in January 1999. Ms. Schenk was previously an attorney in private practice from 1996 to 1998 and from 1983 to 1993. Ms. Schenk served as the U.S. Representative for the 49th District of the State of California from 1993 to 1995 and served as the California Secretary of Business, Transportation and Housing from 1980 to 1983. She received her B.A. in Political Science from the University of California at Los Angeles, earned her J.D. from the University of San Diego and attended the London School of Economics.

Ms. Schenk began serving as a Director of IDEC in 1995.

Phillip A. Sharp, Ph.D., Director

Phillip A. Sharp, Ph.D., is Director of the McGovern Institute for Brain Research at the Massachusetts Institute of Technology and has held that position since March 2000. Dr. Sharp also serves as Institute Professor at the Center for Cancer Research at the Massachusetts Institute of Technology, a position he has held since 1999. From 1991 to 1999, Dr. Sharp served as Salvador E. Luria Professor and Head of the Department of Biology at the Center for Cancer Research at the Massachusetts Institute of Technology. From 1985 to 1991, Dr. Sharp served as Director of the Center for Cancer Research at the Massachusetts Institute of Technology.

Dr. Sharp began serving as a Director of Biogen in 1982. He is also Director and Chairman of the Scientific Advisory Board, Alnylam Pharmaceuticals, Inc.

Dr. Sharp is a Nobel Laureate.

William D. Young, Director

William D. Young is Chairman and Chief Executive Officer for ViroLogic, Inc. From 1997 to 1999, Mr. Young served as Chief Operating Officer of Genentech. Mr. Young joined Genentech in 1980 as Director of Manufacturing and Process Sciences and became Vice President in 1983. He was promoted to various positions and in 1997 became Chief Operating Officer taking on the responsibilities for all Development, Operations, and Sales and Marketing activities. Prior to joining Genentech, Mr. Young was with Eli Lilly & Co., for 14 years. Mr. Young holds a B.S. in Chemical Engineering from Purdue University and a M.B.A. from Indiana University.

Mr. Young began serving as a Director of IDEC in 1997. He is also a Director of VaxGen, Inc. and ViroLogic, Inc.

Mr. Young was elected to the National Academy of Engineering in 1993 for his contributions to biotechnology.