{"nct_id":"NCT00801125","title":"Study of Tysabri (Natalizumab) in Patients Who Failed Anti-TNF-α Therapy","status":"WITHDRAWN","status_verified_date":"2009-01","start_date":"2008-12","start_date_type":null,"primary_completion_date":"2010-05","primary_completion_date_type":"ESTIMATED","completion_date":null,"completion_date_type":null,"phases":["PHASE4"],"tickers":["BIIB"]}