Modeling the Anticipated Public Health Benefits of the Next-Generation COVID-19 mRNA-1283 vaccine: An Interim U.S. Population-Level Impact Assessment

AimsCOVID-19 disease burden in United States (US) older adults [≥]65 years and persons with underlying medical conditions remains high. This modeling study provides an interim estimate of the anticipated public health impact of the next-generation COVID-19 mRNA-1283 vaccine in these populations at high-risk of severe COVID-19 outcomes. MethodsmRNA-1283 was compared to no vaccination and originally licensed mRNA COVID-19 vaccines mRNA-1273 and BNT162b2. Analyses were conducted using a static decision-analytic model (1-year horizon). Vaccine effectiveness (VE) against infection and hospitalization for mRNA-1283 versus no vaccination was based on the relative VE (rVE) from the Phase 3 pivotal randomized controlled trial comparing mRNA-1283 against mRNA-1273 and mRNA-1273 real-world data. rVE estimates for mRNA-1283 versus BNT162b2 were based on an indirect treatment comparison. Clinical outcomes calculated included total numbers of symptomatic infections, outpatient and long COVID cases, hospitalizations, and deaths. Sensitivity and scenario analyses were performed. ResultsDuring the 2024/2025 season in the US, a single dose of the mRNA-1283 vaccine was estimated to prevent approximately 2.9 (1.3-4.3) million symptomatic infections, 171,000 (77,000-260,000) hospitalizations, and 22,350 (10,050-33,480) deaths compared to no vaccination. Compared to BNT162b2, mRNA-1283 was estimated to avert an additional 0.79 million symptomatic infections, 58,000 hospitalizations, and 7,565 deaths. Compared to mRNA-1273, mRNA-1283 was estimated to avert an additional 0.56 million symptomatic infections, 46,000 hospitalizations, and 5,920 deaths. Across all scenarios the majority of severe COVID-19 cases (i.e., hospitalizations and deaths) were prevented among older adults [≥]65 years. LimitationsThe real-world effectiveness and safety of mRNA-1283 have not yet been established and the relative VE estimates should be validated with real-world data. Future COVID-19 incidence and incidence pattern throughout the season is uncertain. ConclusionsInterim results suggest that the next-generation COVID-19 mRNA-1283 vaccine could substantially reduce the clinical burden of COVID-19 among those at high risk of severe disease. Compared to no vaccination and originally approved mRNA vaccines, mRNA-1283 provides a valuable option to potentially enhance COVID-19 immunization programmes and protection of those most vulnerable.