Importance: Respiratory syncytial virus (RSV) is the leading cause of acute lower respiratory infection in children younger than 5 years; effective prevention strategies are urgently needed.
Objective: To compare the efficacy and safety of monoclonal antibodies for the prevention of RSV infection in infants and children.
Data sources: In this systematic review and network meta-analysis, PubMed, Embase, CENTRAL, and ClinicalTrials.gov were searched from database inception to March 2022.
Study selection: Randomized clinical trials that enrolled infants at high risk of RSV infection to receive a monoclonal antibody or placebo were included. Keywords and extensive vocabulary related to monoclonal antibodies, RSV, and randomized clinical trials were searched.
Data extraction and synthesis: The Preferred Reporting Items for Systematic Reviews and Meta-analyses reporting guideline was used. Teams of 2 reviewers independently performed literature screening, data extraction, and risk of bias assessment. The Grading of Recommendations, Assessments, Developments, and Evaluation approach was used to rate the certainty of evidence. A random-effects model network meta-analysis was conducted using a consistency model under the frequentist framework.
Main outcomes and measures: The main outcomes were all-cause mortality, RSV-related hospitalization, RSV-related infection, drug-related adverse events, intensive care unit admission, supplemental oxygen use, and mechanical ventilation use.
Results: Fifteen randomized clinical trials involving 18 395 participants were eligible; 14 were synthesized, with 18 042 total participants (median age at study entry, 3.99 months [IQR, 3.25-6.58 months]; median proportion of males, 52.37% [IQR, 50.49%-53.85%]). Compared with placebo, with moderate- to high-certainty evidence, nirsevimab, palivizumab, and motavizumab were associated with significantly reduced RSV-related infections per 1000 participants (nirsevimab: -123 [95% CI, -138 to -100]; palivizumab: -108 [95% CI, -127 to -82]; motavizumab: -136 [95% CI, -146 to -125]) and RSV-related hospitalizations per 1000 participants (nirsevimab: -54 [95% CI, -64 to -38; palivizumab: -39 [95% CI, -48 to -28]; motavizumab: -48 [95% CI, -58 to -33]). With moderate-certainty evidence, both motavizumab and palivizumab were associated with significant reductions in intensive care unit admissions per 1000 participants (-8 [95% CI, -9 to -4] and -5 [95% CI, -7 to 0], respectively) and supplemental oxygen use per 1000 participants (-59 [95% CI, -63 to -54] and -55 [95% CI, -61 to -41], respectively), and nirsevimab was associated with significantly reduced supplemental oxygen use per 1000 participants (-59 [95% CI, -65 to -40]). No significant differences were found in all-cause mortality and drug-related adverse events. Suptavumab did not show any significant benefits for the outcomes of interest.
Conclusions and relevance: In this study, motavizumab, nirsevimab, and palivizumab were associated with substantial benefits in the prevention of RSV infection, without a significant increase in adverse events compared with placebo. However, more research is needed to confirm the present conclusions, especially for safety and cost-effectiveness.