Tysabri natalizumab regulatory update

FDA approved the Stratify JCV Antibody ELISA test to stratify the risk of developing progressive multifocal leukoencephalopathy (PML) in patients receiving autoimmune drug Tysabri natalizumab. The agency also approved a corresponding addition to Tysabri's label that identifies anti-JC virus antibody status as a risk factor for developing PML. FDA said the test is the first blood test approved for the indication. ...