Efficacy and safety of BG-12 (dimethyl fumarate) and other disease-modifying therapies for the treatment of relapsing-remitting multiple sclerosis: a systematic review and mixed treatment comparison

Objective: Currently, direct comparative evidence or head-to-head data between BG-12 (dimethyl fumarate) and other disease-modifying treatments (DMTs) is limited. This study is a systematic review and data synthesis of published randomized clinical trials comparing the efficacy and safety of existing DMTs to BG-12 for relapsing remitting multiple sclerosis (RRMS). Methods: A systematic review was conducted by searching MEDLINE, EM BASE, and the Cochrane Library for English-language publications from 1 January 1960 to 15 November 2012. Clinicaltrials.gov, metaRegister of Controlled Trials; and conference proceedings from relevant annual symposia were also hand searched. Two independent reviewers collected and extracted data, with discrepancies reconciled by a third reviewer. Included studies were randomized controlled trials (RCTs) of DMTs (interferon [IFN] beta-1a, IFN beta-1b, glatiramer acetate [GA], BG-12, fingolimod, natalizumab, and teriflunomide) in adults with RRMS. Mixed treatment comparisons were conducted to derive the relative effect size for the included treatments. Annualized relapse rate (ARR), disability progression, and safety outcomes were assessed. Results: BG-12 240 mg twice a day (BID) significantly reduces ARR compared to placebo (rate ratio: 0.529 [95% Cl: 0.451-0.620]), IFNs (0.76 [95% Cl: 0.639-0.904]), GA (0.795 [95% Cl: 0.668-0.947]), and teriflunomide 7 mg and 14 mg (0.769 [95% Cl: 0.610-0.970] and 0.775 [95% Cl: 0.614-0.979]), and does not show a significant difference when compared to fingolimod. Only natalizumab was significantly superior to BG-12 in reducing ARR. BG-12 also demonstrated favorable results for disability and safety outcomes. Conclusion: Based on indirect comparison, BG-12 offers an effective oral treatment option for patients with RRMS with an overall promising efficacy and safety profile compared to currently approved DMTs. Key limitations of the systematic review were the large heterogeneity in patients enrolled and the variability in the definition of outcomes in included trials.