Ivermectin's Role in the Prevention of COVID-19: A Systematic Review and Meta-Analysis

This systematic review was performed to determine the population that benefited from prophylactic ivermectin. Seven databases of health-related studies were searched for eligible trials without language restrictions. Randomized controlled trials (RCTs) and cohort studies investigating ivermectin for coronavirus disease 2019 (COVID-19) prevention were included. Data were pooled using a random-effects model, and subgroups were analyzed by study type and the pre- or postexposure population. The certainty of the evidence was determined by the Grading of Recommendations Assessment, Development, and Evaluation approach. Furthermore, 4 RCTs and 4 cohort studies with a moderate to high risk of bias were included in the analysis. The prophylactic use of ivermectin significantly decreased the overall incidence of COVID-19 (odds ratio [OR], 0.26; 95% confidence interval [CI], 0.16-0.44). Nevertheless, the positive result was not supported by the RCT. Ivermectin was associated with a lower risk of COVID-19 (OR, 0.22; 95% CI, 0.12-0.40) in the preexposure population, whereas no protective effect was observed in the postexposure population (OR, 0.39; 95% CI, 0.09-1.67). In summary, prophylactic ivermectin did not prevent COVID-19 in the postexposure population. Although the protective effect of ivermectin was shown in the overall and preexposure populations, the results were unreliable owing to poor-quality evidence.