Comparative effectiveness of teriflunomide and dimethyl fumarate: A nationwide cohort study

ObjectiveTo compare on-Treatment efficacy and discontinuation outcomes in teriflunomide (TFL) and dimethyl fumarate (DMF) in the treatment of relapsing-remitting multiple sclerosis (RRMS) in a real-world setting.MethodsWe identified all patients starting TFL or DMF from the Danish Multiple Sclerosis Registry and compared on-Treatment efficacy outcomes between DMF using TFL, adjusted for clinical baseline variables and propensity score-based methods.ResultsWe included 2,236 patients in the study: 1,469 patients on TFL and 767 on DMF. Annualized relapse rates (ARRs) in TFL and DMF were 0.16 (95% confidence interval [CI] 0.13-0.20) and 0.09 (95% CI 0.07-0.12), respectively. Relapse rate ratio for DMF/TFL was 0.58 (95% CI 0.46-0.73, p < 0.001). DMF had a higher relapse-free survival proportion at 48 months of follow-up (p < 0.05). We observed no difference in Expanded Disability Status Scale score worsening. Discontinuations due to disease breakthrough were 10.2% (95% CI 7.6%-12.8%) and 22.1% (95% CI 19.2%-25.0%) for DMF and TFL, respectively. A subgroup analysis of ARRs in 708 patients with available baseline MRI T2 lesion amount reported similar results after adjustment.ConclusionWe found lower ARR, higher relapse-free survival, and lower incidence of discontinuation due to disease breakthrough on treatment with DMF compared with TFL.Classification of evidenceThis study provides Class II evidence that for patients with RRMS, DMF is more effective in preventing relapses and has lower discontinuation due to disease breakthrough compared with TFL.