Biogen Idec Identifies Molecule That May Be Key to Central Nervous System Repair and Regeneration

CAMBRIDGE, Mass.--(BUSINESS WIRE)--May 17, 2005--

New Research Could Lead to Potential Pathways for Treating Multiple Sclerosis, Demyelinating Diseases

Biogen Idec (NASDAQ: BIIB), a global biotechnology leader with leading products and capabilities in oncology, neurology and immunology, announced today that Biogen Idec scientists have identified a molecule in the central nervous system (CNS) that may play a pivotal role in CNS repair and regeneration. The research, to be published in the June 2005 edition of Nature Neuroscience, is the first to suggest a role for LINGO-1 in nerve repair and could lead to potential pathways for treating multiple sclerosis (MS) and other demyelinating diseases.

MS is a chronic disease of the CNS in which the body's own immune cells break down myelin, a fatty substance that typically surrounds nerve cells like the insulation around a wire. Without myelin, nerves lose the ability to conduct electrical impulses and eventually die. Current MS therapies can slow the progression of the disease, but none are able to repair the damage that the immune system inflicts on myelin. Although the CNS cells that typically wrap nerves in myelin are present in MS patients, they fail to restore the missing myelin sheath following an immune system attack.

The new research reported by Biogen Idec scientists indicates that LINGO-1 appears to be a molecular switch that controls the ability of these CNS cells to myelinate. The Biogen Idec team discovered that LINGO-1 normally acts to prevent myelination and that the normal function of LINGO-1 could be blocked in laboratory tissue culture.

In experiments, researchers were able to induce CNS cells to generate large quantities of myelin by blocking LINGO-1 and, for the first time ever in a laboratory setting, to wrap it correctly around nerves.

"This research underscores Biogen Idec's commitment to neurology and understanding neurodegenerative diseases such as MS," said Michael Gilman, Ph.D., Biogen Idec's Executive Vice President, Research. "Although it is still uncertain whether we can transform these observations into a therapy, our research team has provided the first indications of a new pathway that may enable us to repair the nerve damage found in patients afflicted by MS and other serious demyelinating diseases."

"This work is of great interest to the field of myelin repair. It shows that there are, in the normal brain, certain factors that serve to exert a regulatory influence - and in the case of LINGO-1, a 'restraining' influence - on the myelination program. The authors provide strong evidence that by inhibiting LINGO-1, myelination becomes much more robust," said David R. Colman, Ph.D., a principal investigator of the Myelin Repair Foundation and Wilder Penfield Professor and Director of the Montreal Neurological Institute and Hospital at McGill University. "The possible therapeutic implications are really quite exciting."

"We believe that the LINGO-1 research has significantly added to the body of knowledge about nerve repair in multiple sclerosis and other demyelinating diseases," said John Richert, M.D., Vice President Clinical and Research Programs at the National Multiple Sclerosis Society. "We hope it will one day lead to improved treatments for MS and the repair of the central nervous system."

This new research builds on papers recently published by Biogen Idec scientists on CNS nerve re-growth and regeneration. Earlier in 2005, Biogen Idec researchers published that a protein alternatively referred to as TAJ or TROY acts as an important part of the receptor on CNS neurons that responds to growth-inhibitory molecules in myelin. Specifically, these molecules prevent the re-growth of neurons following injury. Research on LINGO-1 and TAJ may also provide insight into how to potentially repair damage to the spinal cord.

About Biogen Idec

Biogen Idec creates new standards of care in oncology, neurology 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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