BERLIN—Dimethyl fumarate and teriflunomide have similar efficacy in terms of risk of relapse and worsening of Expanded Disability Status Scale (EDSS) score after one and two years of treatment, according to data presented at ECTRIMS 2018. Significantly more patients have new T2 lesions after two years of teriflunomide, however, compared with dimethyl fumarate, and this outcome may explain an increased treatment withdrawal for lack of efficacy among patients receiving teriflunomide.
Teriflunomide and dimethyl fumarate have been approved as first-line treatments for patients with relapsing-remitting multiple sclerosis (MS). To date, no randomized controlled nor observational studies have compared their relative efficacies. David A. Laplaud, MD, PhD, a team leader at the Center of Research in Transplantation and Immunology in Nantes, France, and colleagues conducted a study to compare the effects of teriflunomide and dimethyl fumarate on clinical and MRI outcomes in patients with relapsing-remitting MS from 34 MS centers participating in the French prospective national cohort of MS patients.
The investigators included 1,770 patients with relapsing-remitting MS in the study. In all, 713 participants received teriflunomide, and 1,057 received dimethyl fumarate. Participants were aged 18 to 65 and had an EDSS score of 0 to 5.5 and an available brain MRI performed within six months before treatment initiation. The outcomes under investigation were the proportion of patients with at least one relapse in the year and the two years following teriflunomide or dimethyl fumarate initiation, the proportion of patients with at least one new T2 lesion at one and two years, the number of patients with an increased EDSS score at one and two years, and reasons for treatment cessation at one and two years. For statistical analyses, the outcomes were modeled with propensity scores and logistic regressions by using weighted likelihood maximization and a robust variance estimator.
The confounder-adjusted proportion of patients with at least one relapse at one and two years of treatment was similar in the teriflunomide group and the dimethyl fumarate group (21.6% vs 20.2% for the first year, 30.4% vs 29.5% at two years). Likewise, a similar percentage of patients had an increase of EDSS score at one and two years in the teriflunomide group (27.4% and 41.6%, respectively) and the dimethyl fumarate group (27.1% and 40.6%, respectively). MRI comparisons, however, revealed that the confounder-adjusted proportion of patients with at least one new T2 lesion at two years was significantly lower in patients treated with dimethyl fumarate, compared with teriflunomide (60.8% vs 72.2%; odds ratio [OR], 0.6). The reason for treatment withdrawal at two years was lack of efficacy in 8.5% of patients who received dimethyl fumarate versus 14.5% of patients who received teriflunomide (OR, 0.54).