Biogen Idec and Elan Corporation, plc announced that the Committee for Medicinal Products for Human Use (CHMP) has adopted a positive opinion for inclusion of an additional risk factor, anti-JC Virus (JCV) antibody status, to the product label for Tysabri (natalizumab) in the European Union (EU). The CHMP has also adopted a positive opinion for the five year renewal of the Marketing Authorisation for Tysabri.

The addition of anti-JCV antibody status as a risk factor allows for a three-factor approach to risk stratification. Prior immunosuppressant therapy and Tysabri treatment duration are established risk factors previously included in the product labelling. This provides an opportunity to identify patients at lower or higher risk for the development of Progressive Multifocal Leukoencephalopathy (PML), an infrequent but serious brain infection.

“We are pleased the CHMP has recommended adding anti-JCV antibody status as a third important risk factor for PML to the Tysabri product label. By identifying and understanding the multiple factors that are part of the benefit-risk equation, patients can be informed and empowered to engage in a discussion with their physician about choosing the right therapy for their MS. We are working diligently to make our CE-marked assay broadly available to European physicians at the time of the product label change,” said Douglas E Williams, PhD, executive vice president, research and development at Biogen Idec. “Patient safety is our utmost concern. We are dedicated to better understanding PML and have several ongoing initiatives designed to identify additional factors that may further mitigate the risk.”

“The decision to prescribe Tysabri requires consideration of an individual's expected or observed benefit, as well as the risk of potential adverse events associated with treatment,” added Eliseo Salinas, MD, MSc., chief medical officer at Elan. “All potential risk factors should be considered when making a decision about the appropriate treatment.”

Tysabri is approved in more than 60 countries. In the US, it is approved for relapsing forms of Multiple Sclerosis (MS) and in the European Union for relapsing-remitting MS. It has advanced the treatment of MS patients with its established efficacy. It has been proven to reduce flare-ups and slow physical disability progression.

Tysabri increases the risk of Progressive Multifocal Leukoencephalopathy (PML), an opportunistic viral infection of the brain that usually leads to death or severe disability. The risk of PML increases with longer treatment duration and in patients treated with an immunosuppressant prior to receiving Tysabri. 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 also 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.

Biogen Idec uses cutting-edge science to discover, develop, manufacture and market therapeutic products for the treatment of serious diseases with a focus on neurological disorders.

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.