RSV prefusion F vaccine for prevention of hospitalization in older adults

The DAN-RSV phase 4 pragmatic randomized trial evaluated the effectiveness and safety of the bivalent RSV prefusion F protein–based vaccine (RSVpreF) in adults aged 60 years and older during the 2024–2025 season in Denmark. A total of 131,276 participants were randomized to receive either RSVpreF or no vaccine, and outcomes were determined using national health registry data. The primary endpoint, hospitalization for RSV-related respiratory tract disease, was significantly reduced in the vaccinated group, with incidence rates of 0.11 versus 0.66 events per 1000 participant-years. This corresponded to a vaccine effectiveness of 83.3% (95% CI, 42.9–96.9). Hospitalization for RSV-related lower respiratory tract disease was reduced by 91.7%, and hospitalizations for respiratory tract disease from any cause were reduced by 15.2%. Vaccine effectiveness was consistent across prespecified subgroups. The incidence of serious adverse events was similar between groups, and no vaccine-related serious adverse events resulted in death. The study had several limitations. The number...