Real-World Experience with Diroximel Fumarate in Patients with Multiple Sclerosis: A Prospective Multicenter Study.

Background: Current literature and a real-world study suggest that diroximel fumarate (DRF) is safer than dimethyl fumarate (DMF) in the treatment of multiple sclerosis (MS). However, no real-world study to date has significantly addressed the efficacy of this treatment.

Objectives: This study aims to elucidate the safety, tolerability, and efficacy of DRF in a real-world setting, utilizing data from a Spanish national registry of patients commencing DRF therapy post-market introduction.

Methods: In this multicenter, prospective observational study, data were collected from MS patients who initiated DRF treatment. The study monitored demographic and clinical characteristics, safety outcomes (including adverse events, reasons for discontinuation, and lymphocyte counts), and efficacy outcomes (radiological and clinical activity).

Results: A total of 195 MS patients across 26 neurological departments were included, predominantly female (79.5%), with a mean age of 42.17 years, and a mean duration of treatment with DRF of 6.3 months. Most patients (70.3%) reported no adverse events, while gastrointestinal issues and flushing were the most common adverse events observed. The majority of patients (84.6%) continued with DRF treatment, with tolerability issues being the primary reason for discontinuation. Efficacy analysis showed low relapse rates post-DRF initiation, with most patients exhibiting stable or improved Expanded Disability Status Scale scores and radiological assessments demonstrating minimal activity.

Conclusion: This comprehensive analysis provides valuable insights into the real-world application of DRF, confirming its safety and tolerability while offering preliminary evidence of its efficacy in managing MS.