Natalizumab and fingolimod have not been compared in controlled trials but only in observational studies, with inconclusive results.

The objective of this study is to compare the effect of natalizumab and fingolimod in reducing disease activity in relapsing-remitting multiple sclerosis (RRMS).

We included all consecutive RRMS patients switched from first-line agents (glatiramer acetate/interferons) to natalizumab or fingolimod, with a follow-up of 24 months. Data of relapses, Expanded Disability Status Scale score and brain magnetic resonance imaging (MRI) scans were collected. We used propensity score (PS) matching and intention-to-treat analysis.

We retained 102 patients in each cohort after PS matching, with similar baseline characteristics. More patients discontinued natalizumab compared to fingolimod (33% vs 11%, p < 0.001), mainly for progressive multifocal leukoencephalopathy (PML) concern. No serious adverse events occurred in the two cohorts. Compared to fingolimod, the natalizumab group presented a higher percentage of relapse-free patients (66% vs 80%, p = 0.015), a higher percentage of disability-improved patients (6% vs 15%, p = 0.033), a lower percentage of MRI-active patients (38% vs 14%, p = 0.001) and a higher percentage of patients with no evidence of disease activity (NEDA-3; 44% vs 70%, p < 0.001) after 2 years of follow-up. Disability worsening was not statistically different in the two groups.

Natalizumab is superior to fingolimod in RRMS patients non-responding to first-line agents.