Dimethyl Fumarate Delays Multiple Sclerosis in Radiologically Isolated Syndrome.

Area of Science:

• Neurology
• Clinical Trials
• Neuroimmunology

Background:

• Radiologically Isolated Syndrome (RIS) is the earliest detectable pre-clinical phase of Multiple Sclerosis (MS).
• Identifying interventions to prevent clinical symptom onset in RIS is crucial for early MS management.

Purpose of the Study:

• To evaluate the efficacy of oral dimethyl fumarate (DMF) in preventing the first clinical demyelinating event in individuals with RIS.
• To assess the safety profile of DMF in this at-risk population.

Main Methods:

• A multi-center, randomized, double-blinded, placebo-controlled trial (ARISE study) involving 87 participants with RIS.
• Participants received either oral DMF 240 mg twice daily or placebo for 96 weeks.
• The primary endpoint was the time to the first clinical CNS demyelinating event.

Main Results:

• Dimethyl fumarate significantly reduced the risk of a first clinical event by 82% (HR=0.18, p=0.007) over 96 weeks.
• Moderate adverse reactions were more frequent in the DMF group (32%) compared to placebo (21%).
• Severe adverse events were similar between the DMF (5%) and placebo (9%) groups.

Conclusions:

• This is the first randomized clinical trial demonstrating that a disease-modifying therapy (DMF) can prevent a first clinical event in individuals with RIS.
• Therapeutic intervention at the pre-clinical RIS stage shows promise in delaying or preventing the onset of symptomatic MS.