Efficacy and safety of natalizumab in multiple sclerosis: interim observational programme results. Butzkueven H, Kappos L, Pellegrini F, Trojano M, Wiendl H, Patel RN, Zhang A, Hotermans C, Belachew S, on behalf of the TYSABRI Observational Program(TOP) Investigators J Neurol Neurosurg Psychiatry. 2014 Feb 14. PMID: 24532785. Abstract CommentRecommendBookmarkWatch