Study to Evaluate the Efficacy and Safety of Dimethyl Fumarate (Tecfidera) and Peginterferon Beta-1a (Plegridy) for the Treatment of Relapsing-Remitting Multiple Sclerosis in Pediatric Participants

Treatment tested

• Dimethyl fumarate

  Kelch-like ECH-associated protein 1 inhibitor

• Peginterferon beta-1a

  Interferon alpha/beta receptor agonist

Placebo or sham

• Placebo

Other measures (5)

Key Inclusion Criteria: * Must have a diagnosis of RRMS as defined by the revised consensus definition for pediatric MS * Must have an EDSS score between 0.0 and 5.0. * Must have a body weight of ≥30 kg * Must have experienced ≥1 relapse in the 12 months prior to randomization (Day 1), or must have evidence of asymptomatic disease activity seen on MRI in the 6 months prior to randomization, or ≥2 relapses in the 24 months prior to randomization (Day 1). Relapse is defined as the occurrence of a clinical demyelination event regardless of whether the event is a first or subsequent demyelinating event. Key Exclusion Criteria: * Participants having primary progressive, secondary progressive, or progressive RMS. * Disorders mimicking MS, such as other demyelinating disorders, systemic autoimmune disorders, metabolic disorders, and infectious disorders. * History of clinically significant cardiovascular, pulmonary, GI, hepatic, renal, endocrinologic, hematologic, immunologic, metabolic, dermatologic, growth, developmental, psychiatric (including depression), neurologic (other than MS), and/or other major disease and/or laboratory abnormality indicative thereof, that would preclude participation in a clinical study * Occurrence of an MS relapse within the 30 days prior to randomization (Day 1) and/or the subject has not stabilized from a previous relapse prior to randomization NOTE: Other protocol defined Inclusion/Exclusion criteria may apply.

The main objective of the study is to evaluate the efficacy of dimethyl fumarate (Tecfidera) and peginterferon beta-1a (Plegridy), both compared with placebo, in pediatric participants with RRMS. The other objectives of this study are to evaluate the safety and tolerability of dimethyl fumarate and peginterferon beta-1a and to assess the effect of dimethyl fumarate and peginterferon beta-1a, both compared with placebo, on additional clinical and radiological measures of disease activity.