UCB and Biogen Idec's Oral VLA-4 Antagonist Enters Phase II Development for Multiple Sclerosis BRUSSELS, Belgium & CAMBRIDGE, Mass. -- Jun 26, 2007 - UCB (Euronext Brussels: UCB) and Biogen Idec today announced the initiation of a Phase II study of CDP323 - an oral VLA-4 antagonist - under development for relapsing-remitting multiple sclerosis (MS). The double-blind, randomized Phase II study commenced this week with dosing of the first patient. The study is designed to enroll over 200 patients with relapsing-remitting MS who have failed earlier treatment with a beta-interferon. Last October the companies entered an agreement to co-develop and co-commercialize this small molecule compound. The trial compares the safety and efficacy of two doses of CDP323 monotherapy to placebo over a period of six months. This is the first time that patients with MS will be exposed to CDP323. Approximately 50 medical centers in Europe and the U.S. are expected to participate in this study. The results of this Phase II study are expected by the end of 2008. "Multiple sclerosis affects more than a million people worldwide and so far, no oral treatment has been available. An oral therapy would represent a significant advance for patients as it could provide them with a new, non-invasive option of drug delivery," said Professor Chris Polman, Professor of Neurology, VU Medical Centre, Amsterdam, the Netherlands, Lead Investigator for this study. About CDP323 CDP323 is an orally active small molecule VLA-4 antagonist. The safety, tolerability and pharmacokinetic profile of CDP323 have been evaluated in healthy volunteers in three separate Phase I studies. Data from these studies were reported at the 2006 European Committee for Treatment and Research in Multiple Sclerosis (ECTRIMS). The data from these early studies supports further development of CDP323. About Multiple Sclerosis MS is a chronic disease of the central nervous system that affects approximately 400,000 people in North America and more than one million people worldwide. It is a disease that affects more women than men, with onset typically occurring between 20 and 50 years of age. MS is caused by damage to myelin, the protective sheath surrounding nerve fibers in the central nervous system, which interferes with messages from the brain to the body. Symptoms of MS may include vision problems, loss of balance, numbness, difficulty walking and paralysis. About UCB UCB (www.ucb-group.com) is a leading global biopharmaceutical company dedicated to the research, development and commercialisation of innovative pharmaceutical and biotechnology products in the fields of central nervous system disorders, allergy/respiratory diseases, immune and inflammatory disorders and oncology. UCB focuses on securing a leading position in severe disease categories. Employing over 8,500 people in over 40 countries, UCB achieved revenue of 2.5 billion euro in 2006. UCB is listed on the Euronext Brussels Exchange and its worldwide headquarters are located in Brussels, Belgium. 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. UCB and Biogen Idec Safe Harbor This press release contains forward-looking statements regarding the development of CDP323. Drug development involves a high degree of risk. Only a small number of research and development programs result in commercialization of a product. Factors which could cause actual results to differ materially from UCB's and Biogen Idec's current expectations include the risk that the companies may not be able to demonstrate the safety and efficacy of CDP323 at each stage of the clinical trial process; technical hurdles relating to the manufacture of CDP323 may be encountered; applicable regulatory standards may not be met or regulatory authorities may fail to approve CDP323; and other unexpected hurdles may be encountered. For more detailed information on the risks and uncertainties associated with Biogen Idec's drug development activities, see the section entitled "Risk Factors" in Biogen Idec's quarterly report on Form 10-Q for the fiscal quarter ended March 31, 2007 which was filed with the Securities and Exchange Commission, as well as other periodic and current reports of Biogen Idec filed with the Securities and Exchange Commission. Biogen Idec assumes no obligation to update any forward-looking statements, whether as a result of new information, future events or otherwise.