OBJECTIVE To systematically evaluate the effectiveness and safety of intravenous human immunoglobulin(IVIG) for the treatment of severe and critical COVID-19 patients, to provide a reference for clinical use of the drug.

METHODS PubMed, Embase, Cochrane Library, CNKI and Wanfang database were searched to collect randomized controlled trials(RCTs) or observational studies of IVIG versus conventional treatment for severe and critical COVID-19 patients, and the period of searching was from the establishment of the database to January 2023. The quality of the included literature was evaluated by two investigators who independently screened the literature and extracted information using the Cochrane 5.1.0 risk of bias assessment tool and the Newcastle-Ottawa Scale evaluation scale, and the body of evidence was graded for quality using the GRADE method. Meta-analysis was performed using RevMan 5.3 software and Stata 14.0 software.

RESULTS A total of 5 RCTs and 11 cohort studies involving 3803 patients with severe and critical COVID-19 were included. Meta-analysis showed that IVIG treatment had a slightly lower overall mortality rate in patients with severe or critical COVID-19 than control subjectsRR=0.90, 95% CI(0.75, 1.08), P=0.26, the overall length of hospital stay was slightly higher than that of the control groupMD=1.46, 95% CI(−3.16, 6.08), P=0.54, the overall ICU stay was slightly higher than that of the control groupMD=0.11, 95%CI(−1.32, 1.54), P=0.88, but the differences were not statistically significant; the incidence of adverse effects in the two groups incidence was comparableRR=1.09, 95%CI(0.89, 1.34), P=0.40.

CONCLUSION The use of IVIG does not reduce the mortality rate, length of hospital stay, and ICU stay in patients with severe or critical COVID-19, and therefore the clinical use of IVIG is not recommended for the treatment of patients with severe or critical COVID-19.