Economic evaluation of a bivalent respiratory syncytial virus prefusion F vaccine for older adults in Sweden: cost-effectiveness and budget impact

AIMS: Respiratory syncytial virus (RSV) is a major cause of lower respiratory tract infections among older adults, leading to hospitalizations, higher healthcare costs, and mortality. In Sweden, the bivalent RSV prefusion F (RSVpreF) vaccine was approved in August 2023 for individuals aged 60 years and older, prompting a need for a health economic evaluation. We estimated the cost-effectiveness and budget impact of vaccinating older adults with RSVpreF versus no vaccination in Sweden. METHODS: We implemented a population-based, multicohort Markov model using a lifetime horizon. Costs included direct medical care, vaccination and its administration. Rates of medically attended RSV-related lower respiratory tract infection, case-fatality rates and vaccine effectiveness were estimated by age group, comorbidity profile, and care setting. Adults were characterized based on age (60-74, 75+ years) and comorbidity profile (high risk vs. low risk) and a 75% vaccine uptake was assumed in the base case. We calculated budget impact for a five-year time horizon. RESULTS: The cost-effectiveness model projected fewer RSV-related hospitalizations (-12,9%), outpatient visits (-7,5%), and deaths (-11,3%) with RSVpreF vaccination among high-risk adults aged 60-74 and all adults ≥75 years compared to no intervention, with most benefits within the first 4 years (46,3%, 26,6%, and 46,2% averted, respectively). These reductions lowered direct healthcare costs (-2,8%) and increased QALYs over a lifetime, making RSVpreF cost saving compared to no intervention. In the budget impact analysis, initial investment costs were offset by direct medical savings in year 3, yielding ≈1,76 billion Swedish kronor (approximately 187 million USD) in net savings over five years. CONCLUSION: Introducing RSVpreF vaccination for older adults in Sweden has the potential to reduce RSV-related hospitalizations, deaths, and healthcare costs. Findings support the implementation of RSV vaccination to older adults and at-risk individuals as a cost-effective and budget-saving strategy in the short term.