The consequences of switching from Gilenya® to generics for fingolimod

Background: On May 2017, two generic drugs for fingolimod were introduced into the market in Israel, and most MS patients treated with Gilenya® (Novartis) were switched to fingolimod (Teva), or to Finolim (Rafa). In this study we analyzed the consequences of switching to generic fingolimod in a single MS center. Methods: Study population included relapsing MS patients who were treated with Gilenya® for at least two year before May 2017, switched to generic fingolimod and remained on treatment for at least 2 years thereafter. Data before and after the switch were compared. Results: Twenty-seven patients fulfilled the inclusion criteria (F = 20, RRMS=20, SPMS=7, average age 49±11.4 years, average disease duration=16.6 ± 7.6 years). Seventeen patients had to be switched back to the original Gilenya® due to intolerable new or worsening clinical adverse events (n = 9), clinical relapse (n = 1), clinical relapse with adverse events (n = 3), elevation of liver enzymes > X3 ULN (n = 3) and elevation of amylase (n = 1). Expanded Disability Status Scale (EDSS) score increased in 4 patients during the year before the switch, and in 12 patients during the year of treatment with generic fingolimod (p = 0.036). Conclusion: The tolerability, retention rate and probably efficacy of generic fingolimod seems to be lower than the original Gilenya®.