Comparative efectiveness of neutralising monoclonal antibodies in high risk COVID‑19 patients: a Bayesian network meta‑analysis

The purpose of this work was to review and synthesise the evidence on the comparative efectiveness  of neutralising monoclonal antibody (nMAB) therapies in individuals exposed to or infected with  SARS-CoV-2 and at high risk of developing severe COVID-19. Outcomes of interest were mortality,  healthcare utilisation, and safety. A rapid systematic review was undertaken to identify and synthesise relevant RCT evidence using a Bayesian Network Meta-Analysis. Relative treatment  efects for individual nMABs (compared with placebo and one another) were estimated. Pooled efects  for the nMAB class compared with placebo were estimated. Relative efects were combined with  baseline natural history models to predict the expected risk reductions per 1000 patients treated.  Eight articles investigating four nMABs (bamlanivimab, bamlanivimab/etesevimab, casirivimab/ imdevimab, sotrovimab) were identifed. All four therapies were associated with a statistically  signifcant reduction in hospitalisation (70–80% reduction in relative risk; absolute reduction of 35–40  hospitalisations per 1000 patients). For mortality, ICU admission, and invasive ventilation, the risk  was lower for all nMABs compared with placebo with moderate to high uncertainty due to small event  numbers. Rates of serious AEs and infusion reactions were comparable between nMABs and placebo.  Pairwise comparisons between nMABs were typically uncertain, with broadly comparable efcacy. In  conclusion, nMABs are efective at reducing hospitalisation among infected individuals at high-risk  of severe COVID-19, and are likely to reduce mortality, ICU admission, and invasive ventilation rates;  the efect on these latter outcomes is more uncertain. Widespread vaccination and the emergence  of nMAB-resistant variants make the generalisability of these results to current patient populations  difcult.