Objective: disease-modifying treatments (DMT) for Multiple Sclerosis (MS) have expanded in recent years making the shared-decision process challenging. Moreover, no head-to-head studies are available within the first-line options. Our aim is to compare therapeutic persistence within first-line DMT: teriflunomide (TER), dimethyl fumarate (DMF), and injectable drugs (INJ) in a real-world setting.

Methods: Retrospective observational study analyzing diagnosed with Relapsing-Remitting Multiple Sclerosis (RRMS) who started DMT between January 2015 and April 2022 (TER=117, DMF=117, INJ=123). Clinical, radiological, and demographic variables were collected. The primary outcome was the median time to discontinuation of any DMT. Dropout was defined as discontinuation for 6 months for any reason.

Results: Of the total of 357 patients, 155 withdraw with a median time-to-discontinuation of 1.427 years (IQR 2.410). The discontinuation rate was higher in the injectable group, 49.6%; compared to teriflunomide 40.2%, and dimethyl fumarate 39.8% (p = 0.201). The most frequent reason of discontinuation differs within groups (lack of efficacy in TER, 63.8%, and adverse effects in DMF and INJ (40.4% and 40.9% respectively). No difference in persistence was observed between DMT (p = 0.30). After 2018 there has been a tendency to treat in a quick and early manner (lower EDSS; relapse rate and number of naïve patients), statistically significant for TER (p = 0.005, p = 0.010, and p = 0.045).

Conclusions: Our study demonstrated no differences in persistence between the actual first-line DMT in a real-world setting, although a trend to favor oral-DMT was seen. Reasons for discontinuation differs within groups.