Tysabri natalizumab regulatory update

The European Commission approved an updated label for autoimmune drug Tysabri natalizumab from Biogen Idec and partner Elan to include anti-JC virus antibody status as an additional factor to aid in stratifying patients at risk of progressive multifocal leukoencephalopathy (PML). The anti-JCV antibodies are believed to be a risk factor for developing PML. The partners already market their Stratify JCV anti-JCV antibody assay in the EU. Biogen Idec said it plans to launch the assay in the U.S. this year as a laboratory-developed test. ...