A Study Comparing the Effectiveness and Safety of Teriflunomide and Interferon Beta-1a in Patients With Relapsing Multiple Sclerosis

Primary objective was to assess the effectiveness evaluated by the time to failure of two doses of teriflunomide in comparison to interferon beta-1a in participants with relapsing Multiple Sclerosis \[MS\]. Secondary objectives were: * To assess the effect of the two doses in comparison to interferon beta-1a on: * Frequency of relapses, * Fatigue, * Participant's satisfaction with treatment. * To evaluate the safety and tolerability of the two doses in comparison to interferon beta-1a. The study consisted of a core treatment period with a common end date defined as 48 weeks after randomization of the last participant, followed by an optional long-term extension treatment period until teriflunomide is commercially available in accordance with local regulations.