Cost-Effectiveness of Mixed Maternal RSVpreF/Infant Nirsevimab Immunization Approach vs. Nirsevimab Alone for the Prevention of Respiratory Syncytial Virus in Chile
Author(s)
Rafael Bolaños, MD, PhD, MSc1, Juan Francsico Falconi, MD, MSc2, Ahuva Averin, MPP3, Erin Quinn, BS3, Amy Law, MS, PharmD4, Rengina Kefalogianni, MSc5, Diana Mendes, PhD5.
1Pfizer Value & Evidence Andean Cluster, Lima, Peru, 2Pfizer Vaccines Medical and Scientific Affair, Santiago, Chile, 3Avalere Health, Washington, DC, USA, 4Pfizer Inc, New York, NY, USA, 5Pfizer Ltd., Tadworth, United Kingdom.
1Pfizer Value & Evidence Andean Cluster, Lima, Peru, 2Pfizer Vaccines Medical and Scientific Affair, Santiago, Chile, 3Avalere Health, Washington, DC, USA, 4Pfizer Inc, New York, NY, USA, 5Pfizer Ltd., Tadworth, United Kingdom.
OBJECTIVES: RSVpreF maternal vaccine and nirsevimab monoclonal antibody have both been approved to prevent respiratory syncytial virus (RSV) manifesting as lower respiratory tract illness (LRTI; RSV-LRTI) among infants in Chile. We evaluated the cost-effectiveness of alternative strategies employing a mixed immunization approach (RSVpreF during pregnancy, nirsevimab only for infants not protected by RSVpreF) versus nirsevimab alone to protect Chilean infants.
METHODS: A cohort model was developed to evaluate clinical outcomes (cases, deaths, quality-adjusted life-years [QALYs]) and economic costs (medical, intervention, indirect [work-loss]; 2024US$) associated with RSV-LRTI for infants aged <1 year. Lifetime consequences of RSV-related death and clinical/economic outcomes among women vaccinated during pregnancy were also considered. Nirsevimab cost was $260; RSVpreF cost was $109.9, estimated as the economically justifiable price of year-round RSVpreF alone (vs. no intervention) at willingness-to-pay of 1x gross domestic product per capita. Mixed approach included RSVpreF administered seasonally (MSNL; targeting infants born April-September) or year-round (MYR); in all strategies, nirsevimab was administered at birth (April-September births) or in April/May (October-March births). Uptake was 90% among eligible individuals (both interventions). MSNL and MYR were both compared against nirsevimab alone (NA).
RESULTS: With NA, there were 29,217 cases of RSV-LRTI (including 5,044 hospitalizations); associated costs were $58.7 million (M; medical: $7.1M, intervention: $48.7M, indirect: $2.9M). MSNL prevented 130 hospitalizations (infants: 73, mothers: 57) and reduced total costs by $11.4M (infants: $10.7M, mothers: $0.7M). MYR prevented 329 hospitalizations (infants: 217, mothers: 113) and reduced total costs by $22.7M (infants: $21.3M, mothers: $1.4M). With 34 additional QALYs for MSNL (vs. NA) and 91 additional QALYs for MYR (vs. NA), both strategies yielded dominant cost-effectiveness ratios.
CONCLUSIONS: A mixed approach involving both interventions may offer greater protection against severe RSV illness at a substantially lower cost than nirsevimab alone, especially when considering potential maternal benefits to RSVpreF.
METHODS: A cohort model was developed to evaluate clinical outcomes (cases, deaths, quality-adjusted life-years [QALYs]) and economic costs (medical, intervention, indirect [work-loss]; 2024US$) associated with RSV-LRTI for infants aged <1 year. Lifetime consequences of RSV-related death and clinical/economic outcomes among women vaccinated during pregnancy were also considered. Nirsevimab cost was $260; RSVpreF cost was $109.9, estimated as the economically justifiable price of year-round RSVpreF alone (vs. no intervention) at willingness-to-pay of 1x gross domestic product per capita. Mixed approach included RSVpreF administered seasonally (MSNL; targeting infants born April-September) or year-round (MYR); in all strategies, nirsevimab was administered at birth (April-September births) or in April/May (October-March births). Uptake was 90% among eligible individuals (both interventions). MSNL and MYR were both compared against nirsevimab alone (NA).
RESULTS: With NA, there were 29,217 cases of RSV-LRTI (including 5,044 hospitalizations); associated costs were $58.7 million (M; medical: $7.1M, intervention: $48.7M, indirect: $2.9M). MSNL prevented 130 hospitalizations (infants: 73, mothers: 57) and reduced total costs by $11.4M (infants: $10.7M, mothers: $0.7M). MYR prevented 329 hospitalizations (infants: 217, mothers: 113) and reduced total costs by $22.7M (infants: $21.3M, mothers: $1.4M). With 34 additional QALYs for MSNL (vs. NA) and 91 additional QALYs for MYR (vs. NA), both strategies yielded dominant cost-effectiveness ratios.
CONCLUSIONS: A mixed approach involving both interventions may offer greater protection against severe RSV illness at a substantially lower cost than nirsevimab alone, especially when considering potential maternal benefits to RSVpreF.
Conference/Value in Health Info
2025-11, ISPOR Europe 2025, Glasgow, Scotland
Value in Health, Volume 28, Issue S2
Code
EE260
Topic
Clinical Outcomes, Economic Evaluation, Methodological & Statistical Research
Disease
Pediatrics, Respiratory-Related Disorders (Allergy, Asthma, Smoking, Other Respiratory), Vaccines