Phase III Study With Teriflunomide Versus Placebo in Patients With First Clinical Symptom of Multiple Sclerosis

The study consisted of 4 periods: * Screening period: up to 4 weeks, * Placebo-controlled treatment period: up to 108 weeks (at least 24 weeks for participants who experienced conversion to CDMS), * Extension treatment period (without placebo-control): the extension period continued until teriflunomide was commercially available in participant's country of residence. * Post-treatment washout period: 4 weeks after last treatment intake. The maximal duration of the study period per participant was expected to be 116 weeks if he/she did not continue in the extension treatment period.