TERIKIDS

Treatment tested

• Teriflunomide

  Dihydroorotate dehydrogenase inhibitor

Placebo or sham

• Placebo

Other measures (22)

* Participants with relapsing MS were eligible. Participants who met the criteria of MS based on McDonald criteria 2010 and International Pediatric Multiple Sclerosis Study Group (IPMSSG) criteria for pediatric MS, version of 2012 and had: * at least one relapse (or attack) in the 12 months preceding screening or, * at least two relapses (or attack) in the 24 months preceding screening. * Less than 18 years of age and greater than or equal to (>=) 10 years of age at randomization. Specific for the Russian Federation from 18 December 2014 to 26 July 2016, less than or equal to 17 years of age and >= 13 years of age at randomization. * Signed informed consent/assent obtained from participant and participant's legal representative (parents or guardians) according to local regulations. Exclusion criteria: * Expanded disability status scale score greater than 5.5 at screening or randomization visits. * Relapse within 30 days prior to randomization. * Treated with: * glatiramer acetate, interferons, or dimethyl fumarate within 1 month prior to randomization. * fingolimod, or intravenous immunoglobulins within 3 months prior to randomization. * natalizumab, other immunosuppressant or immunomodulatory agents such as cyclophosphamide, azathioprine, cyclosporine, methotrexate, mycophenolate, within 6 months prior to randomization. * cladribine or mitoxantrone within 2 years prior to randomization. * Treated with alemtuzumab at any time. * History of human immunodeficiency virus infection. * Contraindication for MRI. * Pregnant or breast-feeding females or those who plan to become pregnant during the study. * Female participants of child-bearing potential not using highly effective contraceptive method (contraception in both female and male was required). The above information was not intended to contain all considerations relevant to a participant's potential participation in a clinical trial.

Primary Objective: To assess the effect of teriflunomide in comparison to placebo on disease activity measured by time to first clinical relapse after randomization in children and adolescents 10 to 17 years of age with relapsing forms of multiple sclerosis (MS). Secondary Objective: * To assess the effect of teriflunomide in comparison to placebo on disease activity/progression measured by brain magnetic resonance imaging (MRI) and on cognitive function. * To evaluate the safety and tolerability of teriflunomide in comparison to placebo. * To evaluate the pharmacokinetics (PK) of teriflunomide.