Respiratory Syncytial Virus (RSV) is a leading cause of severe respiratory infections in infants, often resulting in hospitalisation. A recent study from Galicia, Spain, demonstrates the effectiveness of nirsevimab, a long-acting monoclonal antibody, in preventing RSV-related hospitalisations during the 2023-2024 season. The findings offer critical evidence for improving RSV prevention strategies and highlight the potential for universal implementation.
Overview of RSV prevention with nirsevimab
RSV poses a significant risk to infants, particularly those under 24 months. This study evaluated nirsevimab’s ability to protect against RSV-related lower respiratory tract infections (LRTIs), which are a major cause of hospitalisation in this age group. By targeting RSV with a single dose before or during the RSV season, nirsevimab provides a simple and effective method of reducing severe cases. The study’s focus on real-world application underscores its relevance for public health.
Study design and approach
The authors monitored over 14,000 infants in two cohorts: those born during the RSV season and those born just before. Researchers tracked RSV-related hospitalisations and applied statistical analyses to evaluate nirsevimab’s effectiveness. This comprehensive approach provided robust real-world evidence, reinforcing the reliability of the findings.
Key findings on effectiveness
The study revealed substantial benefits of nirsevimab:
- Reduced RSV-related hospitalisations: nirsevimab achieved an 89.2% reduction in RSV-related LRTI hospitalisations overall.
- Protection against severe cases: The risk of hospitalisations requiring oxygen support dropped by 80.3%.
- Broader impact: Hospitalisations due to bronchiolitis and bronchitis decreased by 46%.
These findings highlight nirsevimab’s strong protective effect, with minimal adverse events reported. The study also emphasised its cost-effectiveness, showing that immunising as few as 16-30 infants could prevent one hospitalisation.
Implications for public health policy
With over 90% of eligible infants in Galicia receiving nirsevimab, the study demonstrates its feasibility for widespread use. These results provide a compelling case for policymakers to adopt universal RSV prevention strategies, ensuring better health outcomes for infants worldwide.
Paper available at: THE LANCET: Full 2023–24 season results of universal prophylaxis with nirsevimab in Galicia, Spain: the NIRSE-GAL study
Full list of authors: Mallah, N., Pardo-Seco, J., Pérez-Martínez, O., Durán-Parrondo, C., Martinón-Torres, F., NIRSE-GAL study group
DOI: https://doi.org/10.1016/S1473-3099(24)00811-9