An analysis of first-line disease-modifying therapies in patients with relapsing-remitting multiple sclerosis using the French nationwide health claims database from 2014-2017.

Background: Little is known about the use of first-line treatments for relapsing-remitting multiple sclerosis (RRMS), whether oral (teriflunomide and dimethyl fumarate) or injectable (interferons/glatiramer acetate [GA]) in France. We conducted an observational study to determine patient profile, persistence and compliance to first-line disease-modifying treatments (DMT), and factors related to discontinuation in naïve patients with RRMS.

Methods: This is a retrospective study using the French Nationwide Health Data System (SNDS) which collects outpatient and hospitalization data for the entire population. Naïve patients aged 18 and older, starting first-line DMT between September 1,2014 and August 31,2016, were identified and followed-up until the end of 2017. Treatment persistence identified by the first and last dispensation dates, death, DMT discontinuation ≥6 months, compliance measured by the Medication Possession Ratio (MPR), and number of relapses were estimated.

Results: During the inclusion period, 10,240 patients starting a first-line DMT for RRMS (mainly oral) were identified. Patients treated with teriflunomide were older, more often men with reduced relapses in the year prior to treatment initiation compared to those treated with dimethyl fumarate. Treatment compliance with teriflunomide was 81% [95% CI 80-82] at 6 months and 60% at 24 months [95% CI 58-62] compared to 79% [95% CI 78-80] at 6 months, 55% [95% CI 53-56] at 24 months with dimethyl fumarate versus 74% [95% CI 73-76] at 6 months and 39 % [95% CI 37-41] at 24 months with interferons/GA. After patient profile's adjustment, the risk of discontinuing first-line DMT was higher with interferons/GA and dimethyl fumarate than teriflunomide (HR=1.74, p <0.0001 and HR=1.12, p <0.0001; respectively). Although compliance was good with all treatments, it was significantly better with oral therapies compared to injectables. Probability to relapse at least once in the year after treatment initiation is lower for patients starting oral treatments than those treated with injectables, even after adjusting for patient profile.

Conclusion: This real-world study demonstrated better compliance and persistence to oral therapies in naïve patients initiating first-line DMT for RRMS in France. Within oral therapies, persistence to teriflunomide was higher compared to dimethyl fumarate, with no difference observed in treatment compliance or risk on relapses' occurrence after patient profile's adjustment.