Unlocking the value of RSV vaccination in Japan: a return on investment analysis using an integrated actuarial-macroeconomic model

Objective: Respiratory syncytial virus (RSV) causes significant morbidity and mortality among older adults and individuals with chronic conditions. This study conducted a cost-benefit analysis (CBA) to evaluate the societal value of RSV vaccination with the adjuvanted RSV prefusion F protein (RSVPreF3) vaccine among older adults aged ≥60 years and high-risk adults aged 50-59 years in Japan. Methods: An actuarial population projection model, combined with a full CBA framework adapted to the Japanese setting, was used to estimate costs and benefits of adjuvanted RSVPreF3 vaccination versus no vaccination over a 10-year time horizon. Deterministic sensitivity analyses were conducted to assess parameter uncertainty. Results: Our results indicate that a 5-year vaccination program among older adults, including those aged 50-59 years at higher risk for severe RSV disease and those aged ≥60 years, was associated with substantial economic benefits. Among older adults aged ≥60 years, the total return on investment (ROI) was 3.3 with or without deadweight loss (DWL), with vaccination projected to avert Japanese Yen (JPY) 35,501 M in productive output loss, save JPY 1,178,403 M in direct healthcare costs, and prevent JPY 10,699,729 M in monetized quality-adjusted life-year (QALY) loss. For high-risk adults aged 50-59 years, the total ROI was 3.7 without DWL and 3.8 with DWL, with corresponding reductions of JPY 17,889 M in productive output loss, JPY 10,400 M in healthcare costs, and JPY 266,116 M in monetized QALY loss. Conclusion: Overall, adjuvanted RSVPreF3 vaccination among older adults in Japan represents good value for money from a societal perspective, where vaccine acquisition and administration costs are expected to be outweighed by substantial health, productivity, and broader economic benefits.