Oral teriflunomide in the treatment of relapsing forms of multiple sclerosis: clinical evidence and long-term experience

Key objectives in the treatment of multiple sclerosis (MS) include prevention of relapses, a reduction in the accumulation of disability and slowing of the brain volume loss that occurs from the earliest stages of the disease. Teriflunomide, a once-daily, oral immunomodulatory therapy, has demonstrated efficacy across multiple measures of disease activity and worsening in patients with relapsing forms of MS and in those with a first clinical episode suggestive of MS. In this review, the latest evidence relating to the proposed mechanism of action of teriflunomide in MS is explored, including novel insights provided from the recently completed Teri-DYNAMIC study. Key clinical and magnetic resonance imaging data from the completed long-term extensions of the phase II and III (TEMSO, TOWER and TOPIC) studies are highlighted, and the long-term safety profile of teriflunomide, as evidenced by data from these extension studies, is presented. Although randomized clinical trials represent the highest level of evidence to support the use of therapeutic interventions, it is also important to understand the performance of a particular treatment in the real-world setting. In this regard, the results of the recently completed, global, phase IV Teri-PRO study are of particular interest and provide further insights into the benefits of teriflunomide treatment from the patient perspective. Collectively, the data presented in this review demonstrate a favorable benefit–risk profile for teriflunomide, thereby supporting its long-term use for the treatment of patients with relapsing forms of MS.