Biogen Idec and Elan Corporation, plc announced that data was presented at the 25th Congress of the European Committee for Treatment and Research in Multiple Sclerosis (ECTRIMS) showing the potential of Tysabri (natalizumab) to redefine successful multiple sclerosis (MS) therapy. These data were from observational studies and retrospective analyses of the phase-III AFFIRM clinical trial.

Tysabri significantly improves measures of physical and cognitive disability using the Multiple Sclerosis Functional Composite (MSFC) in patients from the AFFIRM trial with baseline impairment; promoted regeneration or stabilization of damage to the myelin sheath, which can cause some of the symptoms seen in MS patients, as measured by advanced MRI technology; and shows improvement in quality of life as reported by patients.

"MS patients should expect more from an MS therapy and studies such as these demonstrate the potential for Tysabri to satisfy their expectations," said Michael Panzara, vice president and chief medical officer of neurology, Biogen Idec. "These data presented at ECTRIMS show that, for many MS patients, Tysabri may lead to improvement in a broad range of physical and cognitive symptoms."

"The strong efficacy profile demonstrated in clinical trials is enhanced further from these and other important Tysabri data presented at Ectrims," said Carlos Paya, president, Elan Corporation. "Tysabri is the first approved MS therapy with reported data suggesting some signs of the progression of MS can be stopped, whether measured by clinical, radiological or patient-reported measures."

"This data showing the ability of Tysabri to improve both physical and cognitive function represents a new paradigm for defining success in MS therapies," said Frederick E Munschauer, Irvin and Rosemary Smith professor, University of New York, Buffalo, New York.

Natalizumab improves disability on the Multiple Sclerosis Functional Composite in a randomized, double-blind, placebo-controlled study of patients with relapsing multiple sclerosis (poster P434).


About TYSABRI
TYSABRI is approved in more than 40 countries. In the U.S., it is approved for relapsing forms of MS and in the European Union for relapsing-remitting MS. According to data from the Phase III AFFIRM trial published in the New England Journal of Medicine, after two years, TYSABRI treatment led to a 68 percent relative reduction (p<0.001) in the annualized relapse rate, when compared with placebo, and reduced the relative risk of disability progression by 42-54 percent (p<0.001).

TYSABRI is redefining success in the treatment of MS. In post-hoc analyses of the Phase III AFFIRM trial and as published in The Lancet Neurology, 37 percent of TYSABRI-treated patients remained free of their MS activity, compared to seven percent of placebo-treated patients. In addition, data has been presented showing that treatment with TYSABRI significantly increased the probability of sustained improvement in disability in patients with a baseline expanded disability status scale (EDSS) score = 2.0 by 69 percent relative to placebo.

TYSABRI increases the risk of progressive multifocal leukoencephalopathy (PML), an opportunistic viral infection of the brain. Other serious adverse events that have occurred in TYSABRI-treated patients include hypersensitivity reactions (e.g., anaphylaxis) and infections, including opportunistic and other atypical infections. Clinically significant liver injury has been reported in patients treated with TYSABRI in the post-marketing setting. Common adverse events reported in TYSABRI-treated MS patients include headache, fatigue, infusion reactions, urinary tract infections, joint and limb pain and rash.

Tysabri is co-marketed by Biogen Idec Inc and Elan Pharmaceuticals, Inc.

Biogen Idec creates new standards of care in therapeutic areas with high unmet medical needs.

Elan Corporation, plc is a neuroscience-based biotechnology company committed to making a difference in the lives of patients and their families by dedicating itself to bringing innovations in science to fill significant unmet medical needs that continue to exist around the world.