Efficacy and tolerability of minocycline augmentation therapy in schizophrenia: a systematic review and meta-analysis of randomized controlled trials.

OBJECTIVE This study aimed to perform a comprehensive meta-analysis of minocycline augmentation therapy in patients with schizophrenia receiving antipsychotic agents. METHODS Data published up to 2 June 2014 were obtained from the PubMed, PsycINFO, Google Scholar, and Cochrane Library databases.We conducted a systematic review and meta-analysis of patient data from randomized controlled trials (RCTs) comparing minocycline with placebo. Relative risk (RR), standardized mean difference (SMD), and 95% confidence intervals were calculated. RESULTS We included four RCTs. The total sample included 330 patients. Minocycline was superior to placebo for decreasing Positive and Negative Syndrome Scale (PANSS) total scores (SMD=0.70), PANSS negative subscale scores (SMD=0.86), and PANSS general subscale scores (SMD=-0.50) but was not different from placebo for PANSS positive subscale scores (SMD=0.26) and depressive symptoms (SMD=0.28). Minocycline was equivalent to placebo for all-cause discontinuation (RR=1.10), discontinuation due to inefficacy (RR=0.42), discontinuation due to adverse events (RR = 1.56), and discontinuation due to death (RR = 3.18). Minocycline was superior to placebo for extrapyramidal side-effect scores (SMD=0.32). CONCLUSIONS Minocycline may improve the psychopathology of schizophrenia, especially the negative symptoms, and seems to be well tolerated.