DOMINATING RSV: COST-EFFECTIVENESS OF CLESROVIMAB IN INFANTS BORN TO UNVACCINATED MOTHERS IN ARGENTINA
Author(s)
Lucas Perelli1, Mauricio Caballero, PhD2, Guoming Shi, MSc3, Alan Ruiz, BsC4, Natalia Tassara, MD4, Klodeta Kura, PhD5, Raquel Aguiar-Ibáñez, BS, MSc6.
1buenos aires, Argentina, 2Centro INFANT UNSAM, Buenos Aires, Argentina, 3Amaris Consulting UK LTD, London, United Kingdom, 4MSD ARGENTINA S.R.L., buenos aires, Argentina, 5MSD, London, United Kingdom, 6Merck Canada, Toronto, ON, Canada.
1buenos aires, Argentina, 2Centro INFANT UNSAM, Buenos Aires, Argentina, 3Amaris Consulting UK LTD, London, United Kingdom, 4MSD ARGENTINA S.R.L., buenos aires, Argentina, 5MSD, London, United Kingdom, 6Merck Canada, Toronto, ON, Canada.
OBJECTIVES: To estimate the projected cost-effectiveness of introducing clesrovimab versus nirsevimab, both administered seasonally with catch-up, for the prevention of respiratory syncytial virus (RSV) infections in infants entering their first RSV season in Argentina.
METHODS: A published static decision tree model with a 12-month time horizon post-dose was adapted for Argentina. Two populations were analyzed: (1) infants born to mothers who did not receive maternal RSV vaccination, and (2) high-risk infants (i.e., preterm <32 weeks of gestational age or with congenital heart disease or chronic lung disease, regardless of maternal vaccination status). Efficacy inputs were derived from randomized clinical trials, while epidemiological, healthcare resource inputs and unit costs were obtained from Argentinian sources. Outcomes included RSV-related medically attended lower respiratory tract infections (hospitalizations, emergency department visits, outpatient visits, recurrent wheezing, RSV-related deaths), quality-adjusted life years (QALYs) lost and incremental cost-effectiveness ratios. Deterministic and probabilistic sensitivity analyses were conducted.
RESULTS: Among infants born to unvaccinated mothers, clesrovimab reduced RSV visits (-3,152) and deaths (-3), increased QALYs (123.32), and saved costs (-$1.78 million USD at parity price) compared to nirsevimab. In high-risk infants, clesrovimab decreased RSV visits (-351), increased QALYs (13.01), and reduced costs (-$361,482 USD). Deterministic sensitivity analysis identified immunization cost, coverage rate and efficacy as key drivers. Probabilistic sensitivity analysis confirmed a high probability of clesrovimab being cost-effective at a willingness-to-pay threshold of $13,620 per QALY gained (67% for infants born to unvaccinated mothers and 77% for high-risk infants).
CONCLUSIONS: At parity price, clesrovimab dominated nirsevimab, providing greater health benefits at lower costs for RSV prevention in infants in Argentina. The largest gains were achieved among all infants not covered by maternal vaccination, underscoring the value of extending protection beyond high-risk groups. These findings support the adoption of clesrovimab as a cost-effective (dominant) strategy in national immunization programs.
METHODS: A published static decision tree model with a 12-month time horizon post-dose was adapted for Argentina. Two populations were analyzed: (1) infants born to mothers who did not receive maternal RSV vaccination, and (2) high-risk infants (i.e., preterm <32 weeks of gestational age or with congenital heart disease or chronic lung disease, regardless of maternal vaccination status). Efficacy inputs were derived from randomized clinical trials, while epidemiological, healthcare resource inputs and unit costs were obtained from Argentinian sources. Outcomes included RSV-related medically attended lower respiratory tract infections (hospitalizations, emergency department visits, outpatient visits, recurrent wheezing, RSV-related deaths), quality-adjusted life years (QALYs) lost and incremental cost-effectiveness ratios. Deterministic and probabilistic sensitivity analyses were conducted.
RESULTS: Among infants born to unvaccinated mothers, clesrovimab reduced RSV visits (-3,152) and deaths (-3), increased QALYs (123.32), and saved costs (-$1.78 million USD at parity price) compared to nirsevimab. In high-risk infants, clesrovimab decreased RSV visits (-351), increased QALYs (13.01), and reduced costs (-$361,482 USD). Deterministic sensitivity analysis identified immunization cost, coverage rate and efficacy as key drivers. Probabilistic sensitivity analysis confirmed a high probability of clesrovimab being cost-effective at a willingness-to-pay threshold of $13,620 per QALY gained (67% for infants born to unvaccinated mothers and 77% for high-risk infants).
CONCLUSIONS: At parity price, clesrovimab dominated nirsevimab, providing greater health benefits at lower costs for RSV prevention in infants in Argentina. The largest gains were achieved among all infants not covered by maternal vaccination, underscoring the value of extending protection beyond high-risk groups. These findings support the adoption of clesrovimab as a cost-effective (dominant) strategy in national immunization programs.
Conference/Value in Health Info
2026-11, ISPOR Europe 2026, Vienna, Austria
Value in Health, Volume 29, Issue 12S
Code
EE552
Topic
Economic Evaluation, Epidemiology & Public Health, Health Technology Assessment
Disease
Biologics & Biosimilars, Pediatrics, Vaccines