Safety and effectiveness of diroximel fumarate in relapsing forms of multiple sclerosis: a systematic review and meta-analysis

To evaluate the safety and efficacy of Diroximel Fumarate (DRF) in patients with different relapsing forms of MS (RMS) through systematic review and meta-analysis.

A systematic review and meta-analysis adhering to PRISMA guidelines was conducted. Scopus, PubMed, and Cochrane CENTRAL databases were searched until December 6, 2024, for clinical trials and observational studies on DRF in RMS. Eligibility criteria included studies evaluating DRF’s safety or efficacy, excluding case reports and non-clinical outcomes. The risk of bias was assessed using the Newcastle–Ottawa Scale and ROBINS-I tools. Statistical analyses were performed using OpenMetaAnalyst, focusing on pooled mean differences and incidence rates with 95% confidence intervals.

Seven studies with 3,075 participants were included. The overall persistence rate was 75.6% (95% CI: 63.5%, 87.7%). The discontinuation rate due to safety concerns was 6.1% (95% CI: 4.1%, 8.1%). Lymphocyte count decreased significantly by -355.02 cells/µL (95% CI: -636.71, -73.32). Mild adverse events (AEs) occurred in 33% (95% CI: 18.6%, 47.4%), moderate in 30% (95% CI: -9.9%, 69.9%), and severe in 5% (95% CI: -3.8%, 13.7%). Gastrointestinal (GI) AEs were observed in 17.4% (95% CI: 6%, 28.8%), flushing in 18.5% (95% CI: 5.7%, 31.3%), and lymphopenia in 24.3% (95% CI: 10.2%, 38.4%). The relapse rate was 7.1% (95% CI: -4.8%, 19%).

DRF demonstrates efficacy in reducing relapse rates and offers an improved safety profile compared to its predecessor, Dimethyl Fumarate (DMF), particularly in GI tolerability. However, lymphopenia requires monitoring. Further research is recommended to evaluate long-term safety and efficacy in diverse populations.