Optimizing Drug Selection in Children with Multiple Sclerosis: What Do We Know and What Remains Unanswered?

Pediatric-onset multiple sclerosis (POMS) refers to multiple sclerosis with onset before 18 years of age. It is characterized by a more inflammatory course, more frequent clinical relapses, and a greater number of magnetic resonance imaging (MRI) lesions compared with adult-onset MS (AOMS), leading to significant impacts on both disability progression and cognitive outcomes in affected individuals. Managing POMS presents distinct challenges due to the unique needs of pediatric patients and the limited number of disease-modifying therapies (DMTs) approved for pediatric use. Notably, only one therapy (fingolimod) is approved by the United States (US) Food and Drug Administration (FDA) and three (fingolimod, teriflunomide, and dimethyl fumarate) by the European Medicines Agency (EMA) for use in youth with MS. However, observational evidence identifies use of almost all agents off-label in this population. This review provides a comprehensive overview of literature supporting the use of DMTs for POMS, including evidence from observational studies. In this paper, we highlight the shift in clinical practice, which has led to increased use of high-efficacy therapies (HETs) at or near disease onset. We review emerging evidence indicating better cognitive and motor outcomes in this population with early initiation of therapy. Finally, in this paper, we provide a suggested treatment algorithm for managing POMS. We underscore the need for personalized approaches in POMS management. We identify special considerations unique to pediatric care, including attention to family dynamics, and strategies to improve medication adherence and a smooth transition to adult care. Further research on DMTs in POMS is essential to optimize outcomes and improve long-term prognosis.