TENERE

Treatment tested

• Teriflunomide

  Dihydroorotate dehydrogenase inhibitor

Compared with

• Interferon beta-1a

  Interferon alpha/beta receptor agonist

Other measures (6)

Inclusion Criteria: * Relapsing form of MS meeting McDonald's criteria for MS diagnosis and Expanded Disability Status Scale [EDSS] score ≤5.5 at screening visit. Exclusion Criteria: * Significantly impaired bone marrow function or, significant anemia, leukopenia or thrombocytopenia; * Persistent significant or severe infection. * Liver function impairment or known history of hepatitis. * Use of adrenocorticotrophic hormone [ACTH] or systemic corticosteroids for 2 weeks prior to randomization. * Human immunodeficiency virus [HIV] positive. * Prior use of Rebif®, or prior or concomitant use of other interferons in the 3 months prior to randomization. * Prior or concomitant use of cladribine, mitoxantrone, or other immunosuppressant agents such as azathioprine, cyclophosphamide, cyclosporin, methotrexate, mycophenolate, or natalizumab. * Pregnant or breast-feeding woman. Extension criteria: The participants who met all the following criteria at the end of the core study period were eligible for enrolment into the open-label extension phase: * Participants who had not discontinued treatment in the core period and who had a minimum treatment of 48 weeks and completed the EOT visit (Visit 18). * Participants who had not met criteria for treatment withdrawal. * An informed consent must be obtained in writing from the participant for this open-label extension phase prior to entering and prior to completion of any extension phase procedure. * Participants who demonstrated a willingness and ability to roll over to the extension phase with the opportunity to continue treatment on 14 mg/day of teriflunomide under open-label. The above information is not intended to contain all considerations relevant to a participant's potential participation in a clinical trial.

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.