Hydroxychloroquine for treatment of COVID-19 patients: a systematic review and meta-analysis of randomized controlled trials

Objective: We performed a systematic review of the literature and meta-analysis on the efficacy and safety of hydroxychloroquine to treat COVID-19 patients. Methods: We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, and LILACS (January 2019 to March 2021) for patients aged 18 years or older, who had COVID-19 and were treated with hydroxychloroquine versus placebo or standard of care. We also searched the WHO Clinical Trials Registry for ongoing and recently completed studies, and the reference lists of selected articles and reviews for possible relevant studies, with no restrictions regarding language or publication status. Random-effects models were used to obtain pooled mean differences of treatment effect on mortality, and serious adverse effects between hydroxychloroquine and the Control Group (standard of care or placebo); heterogeneity was assessed using the I-2 and the Cochran 's Q statistic. Results: Nine studies met the inclusion criteria and were included in the meta-analysis. There was no significant difference in mortality rate between patients treated with hydroxychloroquine compared to standard of care or placebo (16.7% versus 18.5%; pooled risk ratio 1.09; 95% confidence interval: 0.99-1.19). Also, the rate of serious adverse effects was similar between both Groups, Hydroxychloroquine and Control (3.7% versus 2.9%; pooled risk ratio 1.22; 95% confidence interval: 0.76-1.96). Conclusion: Hydroxychloroquine is not efficacious in reducing mortality of COVID-19 patients.