The Potential Public Health Impact of the Adjuvanted Respiratory Syncytial Virus Prefusion F Protein Vaccine Among Adults Aged 60 and Older in Italy: Preliminary Results of a Markov Model Analysis

OBJECTIVES: Respiratory syncytial virus (RSV) is a highly contagious respiratory virus that has a substantial impact on the health of older adults aged ≥60 years (OA). Based on Savic et al, RSV infection in OA in Italy is estimated to lead to >291,000 RSV-associated acute respiratory infections, >26,000 hospitalizations, and >1,800 deaths each year. Adjuvanted RSVPreF3 OA is the first vaccine approved in Europe for the prevention of lower respiratory tract disease (LRTD) caused by RSV in adults aged ≥60 years. The aim of this study is to evaluate the potential public health impact of vaccination with the adjuvanted RSVPreF3 OA vaccine in OA in Italy.

METHODS: A Markov-cohort model with a 1-year time horizon, representing one RSV season, was adapted to the Italian healthcare setting, and was used to estimate the public health impact of the adjuvanted RSVPreF3 OA vaccine, in comparison with no vaccination, in OA in Italy. Demographic, epidemiologic, and cost data were derived from Italian specific sources and published literature, while vaccine efficacy and waning rates were estimated from the AReSVi-006 phase 3 clinical trial. In the base-case analysis, a coverage rate of 65% was assumed.

RESULTS: In the base case analysis, compared to no vaccination, the adjuvanted RSVPreF3 OA vaccine targeting adults ≥60 years was predicted to reduce the number of RSV-LRTD events by at least 53%, leading to a reduction in associated hospitalizations, complications (i.e., pneumonia cases), and deaths. Vaccine efficacy beyond a 1-year time horizon was explored as a scenario analysis and may help to provide further insights.

CONCLUSIONS: By reducing RSV associated LRTD and related complications, RSV vaccination with the adjuvanted RSVPreF3 OA vaccine could substantially reduce RSV burden in adults ≥60 years in Italy. This preliminary evidence may support policy makers and clinicians to make more informed decisions about RSV vaccination.