Over the last 20 years, there have been significant advances in multiple sclerosis (MS) therapeutics, with regulatory approval for 13 therapies in adults by the European Medicines Agency (EMA) and Food and Drug Administration. However, there is only limited approval for interferon-β and glatiramer acetate use in children 12 years and older by the EMA. Availability of disease-modifying therapies to children and adolescents with MS is variable by region, and is extremely limited in some regions of the world. Up to 30% of children experience breakthrough disease requiring therapies beyond traditional first-line agents. Recent legislation in both the United States and Europe has mandated clinical studies for all new therapeutics applicable to children. Several clinical trials in children are underway that will provide important information regarding the efficacy and safety of newer drugs. This review summarizes the current knowledge of breakthrough disease, escalation, and induction treatment approaches in children with MS, especially pertaining to disease course and disability outcomes in this group of patients. In addition, ongoing clinical trials and approaches and challenges in conducting clinical trials in the pediatric population are discussed.