Multimodal evoked potentials follow up in multiple sclerosis patients under fingolimod therapy

Background Clinical trials have shown the therapeutic effect of fingolimod in reducing disease activity in relapsing-remitting multiple sclerosis (RR-MS), but its influence on nervous conduction assessed by evoked potentials (EPs) has not been previously investigated. Methods EP data of 20 patients examined 12 months prior to initiation of fingolimod (t = −1), at treatment initiation (t = 0) and 1 year later (t = +1) were compared. Each EP (VEP, MEP, SEP) and EP sum score, a global evoked potential score as the sum score of the each EP score was evaluated and correlated with Expanded Disability Status Scale (EDSS). Results During pre-treatment period (1 year) EDSS worsened while one year after fingolimod treatment EDSS remained stable. From t − 1 to t0 VEP, SEP, MEP and EP sum score worsened while from t0 to t + 1 VEP, SEP and EP sum score improved, and MEP score remain stable. VEP and SEP were related to EDSS at baseline (t = −1), while MEP and total EP sum score were related to EDSS at all time points. Conclusion Fingolimod is able to improve visual and somatosensory evoked potential in RR-MS patients even if clinical disability scale remains stable. VEP and SEP could give eloquent information on pathway underweighted in EDSS. EPs are useful to evaluate fingolimod effects in clinical practice.