Recently, the growing number of first-line Disease Modifying Therapies (DMTs) available in clinical practice increased the complexity of treatment choices in naive Relapsing Remitting Multiple Sclerosis (RRMS).
We aimed to evaluate if baseline factors such as older age, being a childbearing-aged woman and having comorbidities influenced the choice of the first-line DMT and to analyze switching patterns between different first-line DMTs in a real-world sample.
We included all consecutive RRMS patients diagnosed between 2016-2020 with a minimum follow-up of 6 months, proposed to an EMA-approved first-line DMT. The DMTs were dichotomized as injectable (BRACE) vs oral DMTs (dimethyl fumarate, teriflunomide). We performed a binary regression to assess if age ≥ 55 years, being a childbearing-aged woman and having comorbidities influenced DMT choice.
The risk of DMT switch at follow-up was evaluated using a Kaplan-Meyer survival analysis with a log-rank test.
107 patients were included in the analysis, 71 (66.4%) female, mean age 35.7±12.1 years. The majority of patients starting a first-line treatment (58.9%) started an oral DMT.
Childbearing-aged women were almost 3 times more likely to be proposed to injectable treatment (OR 2.860, 95%CI 1.191-6.864, p=0.019), while older age and the presence of comorbidities did not influence DMT choice (p>0.05).
During a mean follow-up of 23.6 months, 34 (31.8%) patients switched treatment, the majority (61.8%) due to treatment failure. The survival analysis revealed a higher risk of treatment switch during follow-up in patients starting injectable DMTs (HR 0.475, 95%CI 0.240-0.943, log rank p=0.029).
The oral DMTs have become the most common first-line treatment in the contemporary management of naive-RRMS. Being a childbearing-aged woman, however, seemed determinant in the proposal for an injectable DMT, probably due to the higher safety of these drugs during pregnancy.
The oral DMTs were associated with a lower risk of treatment switch and might be considered from early stages on to enhance treatment persistence.