Real‐life clinical use of natalizumab and fingolimod in Austria
High treatment efficacy of natalizumab and fingolimod for relapsing‐remitting multiple sclerosis (RRMS) has been proven in randomized trials.1 In comparison with placebo groups, natalizumab reduced the annualized relapse rate (ARR) by 68%,1 fingolimod by 48%‐55%.2 In addition, fingolimod showed a reduction in the ARR by 52% vs interferon beta‐1a.4 However, clinical efficacy is difficult to compare directly from these pivotal trials because the ARR in the placebo arms were considerably different, namely 0.81 in the natalizumab trial1 and 0.40 in the fingolimod studies.2 No randomized head‐to‐head studies comparing natalizumab and fingolimod are available for this purpose. Studies matching the clinical efficacy after switching from first‐line therapy provided conflicting results. Some studies revealed equal efficacy,5 whereas another one suggested superiority for natalizumab.7 Recent data from the Danish Multiple Sclerosis Register showed no significant difference regarding ARR, disease progression and mean time to a first relapse in propensity score‐matched cohorts.8 Discrepancies were also observed in studies regarding the clinical course after switching from natalizumab to fingolimod. Cohen et al9 showed a reactivation of clinical activity in the washout period of natalizumab before fingolimod initiation, whereas other studies did not observe any recurrence or rebound relapse activity in the switching period from natalizumab to fingolimod.10
These discrepancies ask for further investigations to confirm or rebut the published findings.
The objective of our study was first to compare the efficacy of natalizumab and fingolimod and second, to analyse the probability for switching from either therapy in a nationwide observational cohort using prospectively collected data from a real‐life setting.