Dimethyl fumarate superior to teriflunomide for preventing relapse in RRMS
Dimethyl fumarate (DMF) appears to prevent relapse more effectively in relapsing-remitting multiple sclerosis (RRMS) compared with teriflunomide (TFL), as shown in the results of a real-world study.
“In this nationwide population-based register study, we provide Class II evidence of an ≈42-percent lower annualized relapse rate in patients treated with DMF compared with patients treated with TFL,” the study authors said. “Furthermore, we provide evidence of a lower risk of a first relapse and a lower incidence of discontinuation due to disease breakthrough in patients treated with DMF.”
The study included 2,236 RRMS patients identified from the Danish Multiple Sclerosis Registry: 1,469 were on TFL (mean age, 41.7 years; 64.0 percent female) and 767 on DMF (mean age, 39.0 years; 75.8 percent female).
During a follow-up of 4,514.5 person-years, 608 patients had a relapse: 433 in the TFL group and 175 in the DMF group. Annualized relapse rate was lower in the latter (0.09; 95 percent CI, 0.07–0.12 vs 0.16; 0.13–0.20), with a rate ratio of 0.58 (0.46–0.73; p<0.001). [Neurology 2019;doi:10.1212/WNL.0000000000007314]
Additionally, the risk of having a first relapse was lower (p=0.0005) and relapse-free survival after 48 months of follow-up was more favourable in the DMF than in the TFL group (p<0.05).
There was no significant between-group difference in Expanded Disability Status Scale (EDSS) score. Mean EDSS score changes during the study period were −0.02 with DMF vs 0.03 with TFL, with 6-month confirmed EDSS score worsening occurring in 63 and 94 patients (p=0.9733), respectively.
Discontinuations due to disease breakthrough occurred more frequently with TFL (22.1 percent vs 10.2 percent), which the authors noted as “a reflection of the higher relapse activity shown in the TFL group.”
In a subgroup analysis of 708 patients with available data on number of baseline MRI T2 lesion, no difference in lesion numbers was observed between treatment groups (p=0.16). Baseline T2 lesion number was not a significant predictor of either annualized relapse rates or relapse rate ratios.
In general, patients treated with DMF tended to be younger, less treatment-naïve and more often female. “This finding quite possibly represents the Danish treatment guidelines having TFL as the default choice of first-line treatment for patients not planning a pregnancy,” the authors said, adding that they were able to account for such difference, which could otherwise lead to indication bias.
Dr Tomas Kalincik from the University of Melbourne in Australia and who is not involved in the study described the process of choosing an oral multiple sclerosis (MS) as complex in that treatment efficacy is only one of the many factors that influence such decisions. [Neurology 2019;doi:10.1212/WNL.0000000000007300]
“The relative effectiveness of MS treatments strongly depends on the context of prior treatment history and disease activity,” he wrote.
Kalincik specified other studies that compared dimethyl fumarate and teriflunomide in various treatment contexts, some of which corroborated the results of the present study. [Eur J Neurol 2018; 26:460-467; Ther Adv Neurol Disord 2018;11:1756286418796404; J Neurol 2019;266:411-416; Curr Med Res Opin 2014;30:613-627; Mult Scler Relat Disord 2016;10:204-212]
“Taken together, the results of the published studies have shown that oral MS immunotherapies are associated with an excellent control of relapse activity, with only minimum differences found between the agents in specific situations,” he wrote.
“[P]atients with no prior exposure to MS immunotherapy tend to benefit more from DMF than TFL. On the other hand, studies that compared cohorts who were mostly switching from other immunotherapies did not find differences in effectiveness between the two agents,” Kalincik added.