Lothar Wiese

Trial registration NCT06684743, registered 9 November 2024 (https://clinicaltrials.gov/study/NCT06684743)

Trial registration Clinicaltrials.gov: NCT05517174

Aims: Atrial fibrillation (AF) is a risk factor for respiratory syncytial virus (RSV)-related adverse cardiac events. This prespecified analysis of the DAN-RSV trial investigated RSVpreF vaccine effectiveness (VE) against respiratory and cardiovascular outcomes among older adults with and without AF. Methods and Results: DAN-RSV was a pragmatic, open-label, individually randomized trial in Denmark during the 2024/2025 winter season. Adults ≥60 years were randomly assigned 1:1 to RSVpreF vaccine or no vaccine. Baseline and endpoint data were obtained from nationwide health registries. The primary endpoint was hospitalization for RSV-related respiratory tract disease, occurring 14 days after study visit until May 31, 2025. Prespecified respiratory and cardiovascular endpoints were assessed by AF status. Among 131,276 participants, 10,126 (7.7%) had a history of AF (mean age 73.2 ± 6.9 years, 30.4% female). AF participants had higher event rates compared with non-AF participants. RSVpreF vaccine lowered the incidence of the primary endpoint with no evidence of effect modification by AF status (AF: VE 80.6% (95%CI -84.7 to 99.6), no AF: VE 84.6% (95%CI 32.3 to 98.3), p-value for interaction >0.99). RSVpreF vaccine was further associated with a lower incidence of all-cause respiratory tract disease hospitalization (AF: VE 25.7% (95%CI -16.9 to 46.1), no AF: VE 13.0% (95%CI -3.3 to 27.8)) and RSV-related and overall cardio-respiratory disease hospitalization with no evidence of effect modification by AF status (p-value for interaction ≥0.45 for all). RSVpreF vaccine was not significantly associated with AF or stroke hospitalizations regardless of AF status (p-value for interaction≥0.34 for all). Conclusions: In older adults, RSVpreF vaccine was associated with a lower incidence of RSV-related and all-cause respiratory tract disease hospitalizations, as well as RSV-related and all-cause cardio-respiratory disease hospitalizations, with no evidence of effect modification by AF status.

Aims: Respiratory syncytial virus (RSV) is a common cause of severe illness in older adults and may cause extra-pulmonary complications. Individuals with chronic kidney disease (CKD) are at increased risk of severe outcomes from respiratory infections, but RSV-specific data are limited. This prespecified analysis of the DAN-RSV trial evaluated the RSV prefusion F protein–based vaccine (RSVpreF) effectiveness (VE) in adults aged ≥60 years with and without CKD. Methods and results: The DAN-RSV trial was a pragmatic, open-label, parallel-group, individually randomized clinical trial conducted during 2024/25. Adults aged ≥60 years were randomized 1:1 to receive respiratory syncytial virus prefusion F (RSVpreF) or no vaccine. Chronic kidney disease was identified using diagnosis codes and biomarkers. Outcomes were assessed through nationwide registry linkage from 14 days post-randomization to 31 May 2025. The primary outcome was RSV-related respiratory tract disease hospitalization; secondary outcomes included respiratory, cardiovascular, and kidney-related hospitalizations, and all-cause mortality. Among 131 276 participants (65 642 RSVpreF; 65 634 controls), 13 364 (10.2%) had CKD. Chronic kidney disease participants were older and had more comorbidities. Hospitalization rates were consistently higher among those with CKD. RSVpreF compared with no vaccine reduced RSV-related respiratory tract disease hospitalization [overall VE: 83.3% (95% confidence interval, CI: 42.9–96.9%); CKD VE: 66.4% (95% CI: −85.2 to 96.7%); no CKD VE: 91.7% (95% CI: 43.7 to99.8%), Pinteraction = 0.29], and cardiorespiratory hospitalization, irrespective of CKD status. Among participants with CKD, a numerical imbalance in mortality was observed; however, event numbers were limited. Conclusion: In this analysis of the DAN-RSV trial, RSVpreF vaccination reduced RSV-related, broader respiratory and cardiorespiratory hospitalizations in older including those with CKD. No significant differences were observed for acute kidney outcomes.