Minocycline for Relapsing-Remitting Multiple Sclerosis and Clinically Isolated Syndrome: A Review of Clinical Effectiveness and Guidelines

Key Message

One relevant randomized controlled trial was identified regarding the clinical effectiveness of minocycline for clinically isolated syndrome. No evidence regarding the clinical effectiveness of minocycline for relapsing-remitting multiple sclerosis was identified. Furthermore, no evidence-based guidelines were identified regarding minocycline for relapsing-remitting multiple sclerosis or clinically isolated syndrome.Limited evidence from this single study indicated that the risk of conversion from clinically isolated syndrome to multiple sclerosis at six months was statistically significantly lower in patients treated with minocycline versus placebo. However, the differences in outcomes were not sustained at 24 months. Relapse rates at six and 24 months were not statistically different between groups. The mean change in Expanded Disability Status Scale score between baseline and the end of the study was not statistically different between groups. Furthermore, the between-group differences at six months on magnetic resonance imaging outcomes (lesions volume, new enhancing lesions, cumulative number of lesions) in favour of minocycline were no longer significant at 24 months, when results were adjusted for the number of enhancing lesions at baseline. Patients treated with minocycline were also found to have statistically significantly greater numbers of adverse events compared to patients treated with placebo. Results from this single study should be interpreted with caution.