Dimethyl fumarate vs Teriflunomide: an Italian time-to-event data analysis

Background: The introduction of oral disease-modifying therapies (DMTs) for relapsing-remitting multiple sclerosis (RRMS) changed algorithms of RRMS treatment. Objectives: To compare the effectiveness of treatment with dimethyl fumarate (DMF) and teriflunomide (TRF) in a large multicentre Italian cohort of RRMS patients. Materials and methods: Patients with RRMS who received treatment with DMF and TRF between January 1st, 2012 and December 31st, 2018 from twelve MS centers were identified. The events investigated were "time-to-first-relapse", "time-to-Magnetic-Resonance-Imaging (MRI)-activity" and "time-to-disability-progression". Results: 1445 patients were enrolled (1039 on DMF, 406 on TRF) and followed for a median of 34 months. Patients on TRF were older (43.5 ± 8.6 vs 38.8 ± 9.2 years), with a predominance of men and higher level of disability (p < 0.001 for all). Patients on DMF had a higher number of relapses and radiological activity (p < .05) at baseline. Time-varying Cox-model for the event "time-to-first relapse" revealed that no differences were found between the two groups in the first 38 months of treatment (HRt < 38DMF = 0.73, CI = 0.52 to 1.03, p = 0.079). When the time-on-therapy exceeds 38 months patients on DMF had an approximately 0.3 times lower relapse hazard risk than those who took TRF (HRt>38DMF = 3.83, CI = 1.11 to 13.23, p = 0.033). Both DMTs controlled similarly MRI activity and disability progression. Conclusions: Patients on DMF had higher relapse-free survival time than TRF group after the first 38 months on therapy.