The aim of this study was to evaluate the efficacy and safety of teriflunomide in reducing the frequency of relapses and progression of physical disability in patients with relapsing multiple sclerosis (RMS). Literatures were searched in Pubmed, Medline and Embase to screen citations from January 1990 to April 2015. Studies of parallel group design comparing teriflunomide and placebo for RMS were screened. After independent review of 234 citations by two authors, seven studies were identified as meeting the inclusion criteria. The results showed teriflunomide (7 and 14 mg) could significantly reduce annualized relapse rate and teriflunomide at the higher dose could also decrease the disability progression (risk ratio (RR) = 0.69, 95% confidence interval (CI): 0.55-0.87). And teriflunomide significantly reduce annualized rates of relapses with sequelae-EDSS/FS, relapses leading to hospitalization, and relapses requiring IV corticosteroids. Patients treated with teriflunomide 14 mg have a lower annualized rate of relapses with sequelae-investigator (RR = 0.37, 95% CI: 0.26-0.52). Teriflunomide 7 mg has a higher incidence of diarrhea (RR =1.73, 95% CI: 1.32-2.26) and hair thinning (RR =1.99, 95% CI: 1.4-2.81), while teriflunomide 14 mg has a higher incidence of diarrhea (RR =1.71, 95% CI: 1.34-2.18), hair thinning (RR = 2.81, 95% CI: 2.02-3.91) and nausea (RR =1.65, 95% CI: 1.03-2.31) compared with placebo. The incidence of elevated alanine aminotransferase levels was also higher with teriflunomide than with placebo. However, the incidence of serious adverse events was similar across groups. In conclusion, teriflunomide significantly reduces annualized relapse rates and disability progression with a similar safety and tolerability profile to placebo. (C) 2016 Elsevier Ltd. All rights reserved.