Key Takeaways:
- Nirsevimab could prevent approximately 14,341 hospitalizations and 14 deaths annually related to RSV.
- Maternal RSV vaccination could prevent around 7,571 hospitalizations and eight deaths each year.
- Both interventions reduce health care costs and productivity losses from RSV but lead to increased overall spending.
Study Overview
A study published in Pediatrics analyzed the cost-effectiveness of nirsevimab, a monoclonal antibody, and maternal respiratory syncytial virus (RSV) vaccination in preventing RSV-related hospitalizations, deaths, and societal costs. RSV causes a significant disease burden in U.S. infants, costing $472 million annually, according to David W. Hutton, PhD, and colleagues at the University of Michigan School of Public Health.
Nirsevimab and Maternal Vaccine Approvals:
- The CDC recommends nirsevimab for infants under 8 months entering their first RSV season and high-risk children up to 19 months entering their second season. Infants born within 14 days of maternal RSV vaccination are also advised to receive nirsevimab.
- Maternal RSV vaccination, approved by the FDA in 2023, is recommended for pregnant women at 32–36 weeks’ gestation to protect infants during their first 6 months.
Nirsevimab Cost-Effectiveness
Simulations showed that if half of infants born during RSV season received nirsevimab:
- Benefits: 107,253 fewer outpatient visits, 38,204 fewer ED visits, 14,341 fewer hospitalizations, and 14 fewer deaths compared to no immunization.
- Costs: Total spending was higher with nirsevimab ($2.085 billion) versus without it ($1.651 billion), largely due to intervention costs ($969 million vs. $225 million). However, RSV-related medical costs ($560 million vs. $755 million) and productivity losses ($556 million vs. $671 million) were lower.
- QALYs Gained: Nirsevimab provided 2,827 additional quality-adjusted life years (QALYs) for children and caregivers, with a societal cost of $153,517 per QALY gained.
- High-Risk Children: For high-risk children, the cost per QALY gained was $308,468. Administering nirsevimab to all children in their second RSV season was unlikely to be cost-effective unless they had a significantly higher risk of severe disease.
Maternal Vaccine Cost-Effectiveness
A similar model evaluated maternal RSV vaccination, excluding nirsevimab:
- Benefits: 45,693 fewer outpatient visits, 15,866 fewer ED visits, 7,571 fewer hospitalizations, and eight fewer deaths annually.
- Costs: Total costs increased with vaccination ($2.164 billion vs. $1.651 billion), mainly due to intervention expenses ($891 million vs. $225 million). However, medical care ($656 million vs. $755 million) and productivity losses ($617 million vs. $671 million) were reduced.
- QALYs Gained: The maternal vaccine resulted in 1,294 additional QALYs at a societal cost of $396,280 per QALY gained.
Timing of Vaccination:
- Administering the vaccine between September and January was most cost-effective, with November offering the lowest cost per QALY ($107,544).
- If the maternal vaccine was used alongside nirsevimab, its cost-effectiveness decreased substantially, with the most cost-effective timing shifting to April, but at a much higher cost ($2.4 million per QALY gained).
Conclusion
The authors emphasized caution when comparing results, as the analyses rely on efficacy trials with differing outcome definitions, and the duration of protection for both interventions remains uncertain. Both strategies hold promise in reducing RSV burden but require careful consideration of costs and implementation.
