Higher Relapse and Adverse Event Rates Reported with Generic Fingolimod vs Gilenya

A retrospective study presented at the 2025 Annual Meeting of The Consortium of Multiple Sclerosis Centers examined clinical and radiologic outcomes in patients with multiple sclerosis (MS) who transitioned from branded Gilenya (Novartis; East Hanover, NJ) treatment to generic fingolimod. The analysis, conducted at a single tertiary MS center, included 88 individuals (81% women; mean age 46.9 y at transition; mean disease duration from time of first symptom of 17.2 y). All participants received Gilenya for ≥1 year before switching to generic fingolimod for at least 6 months.

Compared with those treated with Gilenya, those taking generic fingolimod experienced a 6.6-fold increase in adverse effects (95% CI, 4.19–10.27; P<.0001). Absolute lymphocyte counts rose by 8.7% after the switch between branded and generic treatment (P=.02), suggesting a potential difference in sphingosine-1-phosphate receptor modulation. Notably, relapse activity occurred in 11.4% of individuals on generic fingolimod compared with only 2.3% relapse activity reported in those while on Gilenya treatment. 

These findings raise concerns about the therapeutic equivalence of generic fingolimod, highlighting clinically meaningful differences between generic and Gilenya despite regulatory definitions of bioequivalence.