Efficacy and Safety of Teriflunomide in Chinese Patients with Relapsing Forms of Multiple Sclerosis: A Subgroup Analysis of the Phase 3 TOWER Study

BACKGROUND: Disease-modifying therapy is the standard treatment for patients with multiple sclerosis (MS) in remission. The primary objective of the current analysis was to assess the efficacy and safety of two teriflunomide doses (7 mg and 14 mg) in the subgroup of Chinese patients with relapsing MS included in the TOWER study. METHODS: TOWER was a multicenter, multinational, randomized, double-blind, parallel-group (three groups), placebo-controlled study. This subgroup analysis includes 148 Chinese patients randomized to receive either teriflunomide 7 mg (n = 51), teriflunomide 14 mg (n = 43), or placebo (n = 54). RESULTS: Of the 148 patients in the intent-to-treat population, adjusted annualized relapse rates were 0.63 (95% confidence interval [CI]: 0.44, 0.92) in the placebo group, 0.48 (95% CI: 0.33, 0.70) in the teriflunomide 7 mg group, and 0.18 (95% CI: 0.09, 0.36) in the teriflunomide 14 mg group; this corresponded to a significant relative risk reduction in the teriflunomide 14 mg group versus placebo (−71.2%, P = 0.0012). Teriflunomide 14 mg also tended to reduce 12-week confirmed disability worsening by 68.1% compared with placebo (hazard ratio: 0.319, P = 0.1194). There were no differences across all treatment groups in the proportion of patients with treatment-emergent adverse events (TEAEs; 72.2% in the placebo group, 74.5% in the teriflunomide 7 mg group, and 69.8% in the teriflunomide 14 mg group); corresponding proportions for serious adverse events were 11.1%, 3.9%, and 11.6%, respectively. The most frequently reported TEAEs with teriflunomide versus placebo were neutropenia, increased alanine aminotransferase, and hair thinning. CONCLUSIONS: Teriflunomide was as effective and safe in the Chinese subpopulation as it was in the overall population of patients in the TOWER trial. Teriflunomide has the potential to meet unmet medical needs for MS patients in China. TRIAL REGISTRATION: ClinicalTrials.gov, NCT00751881; https://clinicaltrials.gov/ct2/show/NCT00751881?term=NCT00751881&rank=1