LAY SUMMARY: Respiratory syncytial virus (RSV) is a common cause of lower respiratory tract disease (LRTD) and accounts for significant morbidity and mortality, particularly in older adults. This modelling study evaluated the public health benefits and cost-effectiveness of mRNA-1345, an RSV vaccine, in preventing RSV-related outcomes in people aged =60 years in the UK. The analysis found that mRNA-1345 vaccination reduced RSV-related case numbers, hospitalisations and deaths. mRNA-1345 is cost-effective for preventing RSV-related disease in older adults.
INTRODUCTION: RSV is an important cause of LRTD in older adults. In September 2024, NHS England will introduce its first RSV vaccination campaign, which includes adults aged 75-80 years and those turning 75 years. Countries such as Australia, Canada, the US and France recommend an RSV vaccine for subgroups of people =60 years. This modelling study explored the cost-effectiveness and public health impact of a novel RSV vaccine (mRNA-1345) using clinical trial data for UK adults aged =60 and =65 years.
METHODS: The cost-effectiveness model was built from a UK NHS perspective and used a decision-analytic structure over three years. Based on phase 2/3 clinical trial data (18.8-months median follow-up), mRNA-1345 was presumed to prevent RSV-acute respiratory disease (ARD),RSV-LRTD, and RSV-LRTD hospitalisations amongst those developing infections. To address the known issue of under detection of RSV, the sourced RSV hospitalisation rates were adjusted using a published multiplier of 1.5. Calibration techniques were performed to ensure external validation. Costs, quality-adjusted life-years (QALYs) and population-related parameters were sourced from publicly available sources.
RESULTS: Vaccination of adults =60 years with a single dose of mRNA-1345 results in a 23.8% and 35.1% reduction in RSV-ARD and RSV-LRTD cases over three years, compared with no vaccine, respectively. For a population of 16,814,195 adults =60 years, without RSV vaccination, the annual number of RSV hospitalisations is projected to be 36,696. The annual number of hospitalisations aligns with published literature when adjusted for the under detection of RSV. A single dose of mRNA-1345 is estimated to save 40,558 (38.9%) hospitalisations over three years. The NNV to prevent one RSV-LRTD case, hospitalisation and death is 44, 293 and 527, respectively. There are 39.8% less RSV-related deaths and, consequently, 161,947 life years are gained over three years. Incurred costs from mRNA-1345 implementation are offset by 123,824 QALYs gained to produce an ICER of £14,557 per QALY gained.
The direction of the results for adults =65 years remained consistent. The ICER fell to £12,425 per QALY gained. mRNA-1345 vaccination was estimated to save 38,581 (40.1%) RSV-LRTD hospitalisations over a three-year time horizon in a population of 12,736,451 adults. It was associated with a 25.9% and 37.7% reduction in RSV-ARD and RSV-LRTD cases, respectively.
CONCLUSION: Vaccination with mRNA-1345 could have a substantial impact on reducing RSV-related morbidity and mortality in UK adults aged =60 years. The vaccine could contribute to reducing ongoing winter pressures for the NHS. The ICER for mRNA-1345 is substantially lower than the UK willingness-to-pay threshold of £20,000 per QALY gained, suggesting that RSV vaccination with mRNA-1345 is highly cost effective.