This study aims to compare the long-term outcomes of patients with multiple sclerosis (MS) with and without rebound activity after fingolimod discontinuation.

A total of 31 patients who discontinued fingolimod for various reasons with a minimum follow-up of 5 years were included in the study. Of these, 10 were assigned to the rebound group and 21 to the non-rebound group. Clinical and demographic data and 5-year clinical outcomes of both groups were prospectively examined.

At fingolimod initiation, there were no significant differences in age, disease duration, and Expanded Disability Status Scale (EDSS) score. The annualized relapse rate (ARR) was significantly higher in the rebound group than in the non-rebound group before the fingolimod treatment (P=0.005). In the rebound group, EDSS scores 2 months after rebound treatment and at the 5-year follow-up were not significantly different than before fingolimod initiation (P=0.14 and P=0.46, respectively). The last recorded EDSS was significantly higher in the non-rebound group than in the rebound group (3.6±2.3 vs 2.15±1.4, P=0.045). At the last follow-up, one patient was diagnosed with SPMS in the rebound group (10%), and 11 patients were in the non-rebound group (52.4%, P=0.05).

Fingolimod is highly effective in controlling disease activity and slowing disability progression, although there is a risk of rebound activity after fingolimod discontinuation. We conclude that rebound activity is a good predictor of neuroinflammation in MS and that there is no significant long-term disability worsening in these patients with MS exhibiting rebound after fingolimod cessation who were closely monitored and well-treated.