OBJECTIVE: This analysis estimates the projected impact of a novel vaccine for the prevention of respiratory syncytial virus (RSV) among adults aged ≥ 60 years in the United States (US).
METHODS: A decision tree model followed a cohort of 74,629,409 adults aged ≥ 60 years and compared outcomes for RSV vaccine with no vaccine over a time horizon of 3 years. The model used data from the CYPRESS phase 2 study, which showed an efficacy of 69.8% (year 1) and 56.6% (years 2 and 3) against RSV-positive acute respiratory infection (ARI). Other model input values were obtained from US sources. The analysis assumed 50% vaccine coverage and focused on medically attended and nonmedically attended symptomatic RSV cases. Total and incremental health outcomes as well as the number needed to vaccinate (NNV) were reported undiscounted. One-way sensitivity and scenario analyses were also conducted.
RESULTS: The RSV vaccine resulted in 3,056,723 (−30.6%) fewer symptomatic RSV-positive ARI cases, 123,134 (−30.6%) fewer hospitalizations, and 21,381 (−30.6%) fewer deaths over the 3-year time period when compared with no vaccine. The NNV was 12 per RSV case avoided, 260 per hospitalization avoided, and 1,745 per death avoided. Among all input parameters tested, the results were most sensitive to changes in annual RSV incidence and duration of protection conferred from the vaccine.
CONCLUSION: A durable RSV vaccine for adults that provides protection over multiple RSV seasons is expected to substantially reduce RSV cases, healthcare resource utilization, and deaths among adults aged ≥ 60 years in the US.
