We aimed to determine the effectiveness and safety of high-dose biotin (HDB) in multiple sclerosis (MS) via a systematic review and meta-analysis of randomized controlled trials (RCT).

High-dose biotin (HDB) may activate certain enzymes to increase myelin repair/synthesis and may enhance the production of adenosine triphosphate (ATP), which may be essential to prevent neurodegeneration.

We searched the electronic databases for relevant articles until April 2021 for RCTs that employed HDB for adult MS patients. Certainty of evidence (COE) was evaluated using the GRADE approach.

Out of 366 records identified, three RCTs involving 889 individuals with MS were pooled for analyses. At 12 to 15 months, there is insufficient evidence that HDB and placebo arms differed in terms of composite improvement of MS-related disability (RR 2.87; 95% CI 0.29-28.40; 2 trials; 796 participants; I2=66%) [low COE], improvement in expanded disability status scale (IEDSS) (RR 2.27; 95% CI 0.25-20.98; 2 trials; 796 participants; I2=63%) [low COE], and both IEDSS and improvement in 25-foot walk time (ITW25) (IEDSS-ITW25) (RR 0.58; 95% CI 0.17–2.00; 2 trials; 796 participants; I2=13%) [moderate COE] among patients with progressive MS. Pooled data for ITW25 at 12 to 15 months yielded statistical significance (RR 2.06; 95% CI 1.04-4.09; 2 trials; 796 participants; I2=0%) [moderate COE] favoring HDB among patients with progressive MS. Synthesized data on incidence of any AEs (RR 0.98; 95% CI 0.92-1.04; 3 trials; 889 participants; I2=0%) [high COE] and any serious AEs (RR 0.98; 95% CI 0.77-1.24; 3 trials; 889 participants; I2=0%) [moderate COE] were not significantly different between HDB and placebo groups. Thirty-one patients (4.7%) in the HDB group were found to have laboratory test interference [high COE].

A moderate certainty of evidence suggests a potential benefit in favor of HDB administered for 12 to 15 months in terms of ITW25 in patients with PMS.