# Systematic Review: Efficacy, Safety Profile, and Cost-Effectiveness of Nirsevimab Versus Palivizumab for RSV Prevention in Children Under 24 Months

## TL;DR

Nirsevimab is as effective or more effective than palivizumab for preventing RSV in children, with a simpler dosing schedule and similar safety.

## Contribution

This systematic review compares the efficacy, safety, and cost-effectiveness of nirsevimab and palivizumab for RSV prevention in children under 24 months.

## Key findings

- Nirsevimab showed 70–85% reduction in RSV-related hospitalizations compared to palivizumab's 45–55%.
- Nirsevimab requires only one dose per RSV season, improving adherence to prophylaxis programs.
- Economic analyses suggest nirsevimab may be more cost-effective than palivizumab, especially at lower prices.

## Abstract

What are the main findings?
Nirsevimab demonstrates comparable or superior efficacy to palivizumab in preventing respiratory syncytial virus lower respiratory tract infections in children.Compared with palivizumab, nirsevimab has a more favorable administration profile, requiring only a single dose per RSV season, and has a similar safety profile.

Nirsevimab demonstrates comparable or superior efficacy to palivizumab in preventing respiratory syncytial virus lower respiratory tract infections in children.

Compared with palivizumab, nirsevimab has a more favorable administration profile, requiring only a single dose per RSV season, and has a similar safety profile.

What are the implication of the main findings?
The use of nirsevimab may improve adherence to RSV prophylaxis programs by reducing the need for multiple injections during the RSV season.Nirsevimab represents a potentially cost-effective alternative for large-scale RSV prevention strategies in infants and young children.

The use of nirsevimab may improve adherence to RSV prophylaxis programs by reducing the need for multiple injections during the RSV season.

Nirsevimab represents a potentially cost-effective alternative for large-scale RSV prevention strategies in infants and young children.

Background: Respiratory syncytial virus (RSV) is a leading cause of lower respiratory tract infections (LRTI) in infants and young children, with significant morbidity, hospitalizations, and healthcare costs. Passive immunoprophylaxis has historically relied on palivizumab, while nirsevimab, a long-acting monoclonal antibody, has recently emerged as an alternative and has broader indications. Methods: We conducted a systematic review of randomized controlled trials, observational studies, real-world effectiveness analyses, and economic evaluations assessing the efficacy, safety, and cost-effectiveness of palivizumab and nirsevimab for RSV prevention in children under 24 months. Results: 41 studies were included in this review. Palivizumab demonstrated consistent efficacy in reducing RSV-related hospitalizations in high-risk infants, with relative risk reductions of approximately 45–55%. Nirsevimab showed higher relative efficacy, with reductions of 70–85% in RSV-associated lower respiratory tract infections and hospitalizations across randomized trials and real-world studies, including healthy term and late-preterm infants. Both monoclonal antibodies have favorable safety profiles, with adverse event rates comparable to the placebo. Economic analyses indicated that palivizumab is cost-effective primarily in narrowly defined high-risk populations, whereas nirsevimab may offer improved cost-effectiveness, particularly at lower acquisition prices and with seasonal administration strategies. Conclusions: Nirsevimab represents a promising advancement in RSV prevention, with broader protection, a simpler administration, and potential economic advantages compared to palivizumab.