Is It Too Early to Predict the Failure of Natalizumab in NMO?-Reply. Kleiter I, Hellwig K, Berthele A, Kümpfel T, Linker RA, Hartung H-P, Paul F, Aktas O, Neuromyelitis Optica Study Group(NEMOS) Arch Neurol. 2012 Aug 1; 69(8):1085-6. PMID: 23753805. Abstract CommentRecommendBookmarkWatch