FDA Drug Safety Communication: New risk factor for Progressive Multifocal Leukoencephalopathy (PML) associated with Tysabri (natalizumab)

[01-20-2012] The U.S. Food and Drug Administration (FDA) is informing the public that testing positive for anti-JC virus (JCV) antibodies has been identified as a risk factor for progressive multifocal leukoencephalopathy (PML).
Source: FDA Center for Drug Evaluation and Research - What's New - Category: Drugs & Pharmacology Source Type: news