Natalizumab may reduce cognitive changes and brain atrophy rate in relapsing-remitting multiple sclerosis: a prospective, non-randomized pilot study

BACKGROUND AND PURPOSE: The development of treatment strategies for cognitive impairment in multiple sclerosis (MS) is still in its infancy. The objective of this prospective, non-randomized, pilot study was to assess the possible efficacy of treatment with natalizumab in comparison with interferon beta (IFNB) in a group of relapsing-remitting (RR) patients with MS. METHODS: We included 12 patients treated with natalizumab and 14 with IFNB. At baseline and at follow-up, cognitive functioning was assessed through the Rao's Brief Repeatable Battery. All the patients underwent brain MR study with the assessment of T2 lesion volumes (T2LV), neocortical volume (NCV), normalized brain volume (NBV) and percentage brain volume change (PBVC). Evolution of cognitive performance was assessed using available normative data for the Italian population. Treatment comparisons were assessed through the Mann-Whitney U-test, anova for repeated measures and linear multivariate regression analyses. RESULTS: After a mean follow-up of 1.5 years, the mean number of neuropsychological tests with a deteriorating performance was significantly lower in patients treated with natalizumab (0.7 ± 0.7 vs. 1.7 ± 1.4; P = 0.031). Likewise, PBVC was significantly lower in natalizumab-treated subjects than that observed in patients treated with IFNB (-0.51 ± 0.47% vs. -1.18 ± 0.98%; P = 0.050). CONCLUION: Our results suggest a potential beneficial effect of natalizumab therapy on cognitive functioning in MS, possibly mediated by a reduction of brain atrophy.