Cost-effectiveness of a single dose of the adjuvanted respiratory syncytial virus preFusion protein 3 vaccine over 5 years and its potential public health impact among older adults in Italy.

BACKGROUND: Respiratory syncytial virus-associated acute respiratory illness (RSV-ARI) is an underrecognized cause of illness in older adults aged ≥ 75 years (OAs) and individuals at increased risk (AIR), contributing to a substantial disease burden. AS01E-adjuvanted RSV PreFusion protein 3 vaccine (aRSVPreF3) is approved for the prevention of RSV-associated lower respiratory tract disease (LRTD) in OAs. This study assesses the cost-effectiveness of a single dose of aRSVPreF3 vaccine among OAs and AIR individuals aged 60-74 years over 5 years in Italy. METHODS: A static multi-cohort Markov model with 5-year horizon and 1-month cycle length was developed to model the effect of aRSVPreF3 vaccination. Inputs were obtained from national databases and scientific literature. Sensitivity analyses were performed to assess the robustness of the results to variations in input parameters. RESULTS: At 75% coverage, aRSVPreF3 vaccination was predicted to prevent 1,253,641 and 1,083,247 RSV-ARI cases, and 552,517 and 579,008 RSV-LRTD cases, with direct healthcare costs reduced by €240,849,821 and €331,050,265 over a 5-year period in OAs and AIR individuals, respectively. Vaccination of OAs and AIR individuals was estimated to prevent 58,129 and 102,786 quality-adjusted life-year losses, yielding incremental cost-effectiveness ratios of €13,832 and €4,529, respectively. CONCLUSIONS: Vaccination of OAs and AIR individuals with one dose of aRSVPreF3 has the potential to reduce RSV disease-associated burden and direct costs for the Italian National Healthcare System over a 5-year period. These results could support policymakers and clinicians in decision-making processes around the recommendation and implementation of RSV vaccination in Italy.