Interventions for immune augmentation against SARScoV-2 virus infection via heterologous immunity, active immunity, passive immunity, and immunotherapy: A meta-analysis

ABSTRACT

Background: In this meta-analysis we evaluated strategies on augmentation of host immunity against Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) infection. Method: We searched clinical trials registered at the National Institutes of Health by 30 November 2020, and conducted analyses on inoculated population, involved immunological processes, source of injected components, and trial phases. We then searched PubMed, Embase, Scopus, and the Cochrane Central Register of Controlled Trials for their corresponding reports. A bivariate random-effects meta-analysis was used to derive the pooled estimate of seroconversion and adverse events (AEs). Results: A total of 540,269 participants were enrolled in 225 identified trials. The working mechanisms included heterologous immunity, active immunity, passive immunity, and immunotherapy. A total of 2,565 healthy adults from 10 clinical trials were included for meta-analyses. The odd ratio (OR) was 90.82 for kinetics of serologic responses to anti-SARS-CoV-2 antibody IgG titer (95% CI =36.1-228.49;p < 0.00001). The pooled ORs were 2.57 for solicited systemic AEs (95%CI =1.57-4.21;p = 0.0002), 5.72 for solicited local AEs (95% CI=2.59-12.67;p < 0.0001), and 2.08 for unsolicited systemic events (95% CI=1.42-3.05;p = 0.0002), compared to placebo or conservative treatment. Conclusion: Among all immune-augmentative interventions, a paradigm shift to vaccines providing active immunity was observed. The efficacy of these interventions was promising although systemic adverse events were noted.