OBJECTIVES: To estimate the levels of adherence and persistence of patients with Relapsing-Remitting Multiple Sclerosis (RRMS) and treated with platform therapies in Brazil. METHODS: DATASUS, a nation-wide, anonymized, healthcare claims database was used as primary data source. Naïve patients starting on one of the platform therapies for RRMS, between January and June 2013 were followed for at least 13 months (up to 18), until September 2014) after the first entry in DATASUS (considered for this analysis as treatment initiation). Therapies included intramuscular (IM) interferon beta-1a (IFNβ-1a), subcutaneous (SC) IFNβ-1a, IFNβ-1b, and glatiramer acetate (GA).Adherence was measured as medication possession ratio (MPR), calculated as the proportion of months patients possessed their therapies independently of drug change until the end of the analyzed period, where MPR>0.80 was considered adherent. Persistence was time in months from initiation date until a 30-day gap in therapy or the last claim during follow-up. Chi-square assessed the association between treatments and time on-therapy. Median difference between MPR was assessed through Kruskal-Wallis’ Method. Analyses were performed using R, version 3.1. RESULTS: Total number of patients was 1,052: IM-IFNβ-1a (N=351, 33.4%); IFNβ-1b (N=145, 13.8%); GA (N=264, 25.1%); and SC-IFNβ-1a (N=292, 27.8%). MPR>0.80 was significantly higher (p<0.001) in the IM-IFNβ-1a group (71.8%) versus IFNβ-1b (58.6%), GA (65.5%), and SC-IFNβ-1a (63.7%). There were no consistent differences in persistence between the groups. CONCLUSIONS: While there are limitations in measuring adherence even in controlled trials, MPR seems to be appropriate in real life scenario. Patients initiating treatment with IM-IFNβ-1a showed better adherence than those initiating with other platform therapies for RRMS in Brazil. The literature reports similar efficacy and safety profile among platform therapies, however, they differ in terms of administration route and dose scheduling. Better adherence results for IM-IFNβ-1a may be associated with dosing regimen and convenient administration from an auto-injector device.