Barzilai University Medical Center

44 Research Day 2020 Barzilai University Medical Center 26 GENERICS FOR MULTIPLE SCLEROSIS: GILENYA OR FINGOLIMOD? Leslie Menendez 1 , Michael Osherov 1 , Zeev Nitsan 1,2 , Nurit Hovel 1 , Ron Milo 1,2 1 Department of Neurology, Barzilai University Medical Center, Ashkelon 2 Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva Background On May 2017, a generic fingolimod for multiple sclerosis (MS) was introduced into the market in Israel, and most patients treated with Gilenya (Novartis) were switched to Fingolimod (Teva), or to Finolim (Rafa). Hypothesis Switch to generic fingolimod may alter efficacy, safety and tolerability of the treatment. Objective To analyze the consequences of this switch. Methods Retrospective analysis of data from records of relapsing MS patients who were treated with Gilenya (G) before May 2017, switched to generic fingolimod (F) thereafter and are still continuing treatment. Data within one year before and after the switch were compared. Results Twenty-seven patients (F=20, RRMS=20, SPMS=7, average age 49±11.4, average disease duration=16.6±7.6 y) were identified. Reasons for switching back to only Gilenya in 10 patients included new or worsening adverse effect that were too disturbing (n=9), clinical relapse (n=1), elevation in liver enzymes > X3 ULN (n=1). Liver enzyme abnormalities were detected in 2/27 patients during G treatment and in 4/27 during F treatment (p=NS). There was a trend towards reduced lymphocyte count after G-F switch (644±221 vs. 593±182, p=0.149). Age, disease duration and disease type (RRMS or SPMS) did not predict the need to switch back to G. Conclusion The tolerability of generic fingolimod seems to be lower than the original gilenya. Despite the small number of patients, short follow-up period and the minor or no differences detected in most parameters between F and G treated patients that do not allow for definite conclusions regarding the comparative efficacy and safety of G and F, these results raise concerns about the use of generics, even for simple chemical drugs, in a complex and heterogenous disease such as MS that spans over many domains. This may require biologic and clinical evaluations, not merely the demonstration of bioequivalence, for generic drugs for MS.