{"response":[{"definition":"Tysabri (Natalizumab) is a prescription drug co-marketed by Biogen Idec and Élan as Tysabri. \nIt was previously named Antegren. Natalizumab is administered by infusion every 28 days and \nis used in the treatment of multiple sclerosis and Crohn's disease. In combination with \ninterferon beta-1a the drug has also been linked to two cases of progressive multifocal \nleukoencephalopathy, one of which was fatal.","id":114634,"name":"Tysabri","synonyms":["Tysabri","Natalizumab"],"version":538}]}