Does Initiation of Disease Modifying Therapy in Patients With Radiologically Isolated Syndrome Reduce their Risk of

Aimen Vanood1, Nicholas L Zalewski1, Lisa A Marks2

  • 1Department of Neurology.

The Neurologist
|September 4, 2025
PubMed
Abstract

Insights

Initiating disease-modifying therapy (DMT) for Radiologically Isolated Syndrome (RIS) significantly reduces the time to the first clinical attack of multiple sclerosis (MS). Further research is needed to identify specific risk factors guiding DMT initiation in RIS patients.

Area of Science:

  • Neuroimmunology
  • Radiology
  • Clinical Neurology

Background:

  • Radiologically Isolated Syndrome (RIS) presents as MRI abnormalities mimicking multiple sclerosis (MS) and is considered a preclinical MS stage.
  • Identified risk factors for MS conversion include younger age, specific lesion locations (infratentorial, spinal cord), gadolinium enhancement, and positive cerebrospinal fluid oligoclonal bands.
  • Current guidelines for disease-modifying therapy (DMT) in RIS patients are lacking.

Purpose of the Study:

  • To evaluate the impact of initiating DMT in RIS patients on the time to the first clinical attack of MS.
  • To critically appraise existing evidence on DMT use in the context of Radiologically Isolated Syndrome.
  • To inform clinical decision-making regarding early intervention in preclinical MS.

Main Methods:

  • A structured critically appraised topic (CAT) methodology was employed.
  • Inclusion of a clinical scenario, comprehensive literature search, and critical appraisal of evidence.
  • Expert review by neurologists and neuroimmunology specialists.

Main Results:

  • A randomized controlled trial demonstrated an 82% risk reduction in clinical attacks for patients treated with dimethyl fumarate (DMF) compared to placebo.
  • DMF treatment also led to a decrease in new/enlarging T2 hyperintense lesions.
  • No subgroup analyses were conducted to identify specific risk factors for conversion.

Conclusions:

  • Initiating DMT in RIS patients appears to delay the first clinical attack of MS.
  • Further investigation is required to determine the specific risk factors that should prompt DMT initiation in this population.
  • Evidence suggests a potential benefit of early intervention in managing preclinical MS.