To describe the effect of a single dose of mRNA-1345 vaccine
on the number of participants with first episode of RSV-LRTD
by baseline comorbidities such as COPD, asthma, any chronic
respiratory or pulmonary disease, diabetes mellitus type 1 or 2,
CHF, and advanced liver or renal disease.
To evaluate the safety and tolerability of the mRNA-1345 vaccine
To evaluate the efficacy of a single dose of mRNA-1345 vaccine in the prevention of a first episode of RSV-associated acute respiratory disease (RSV-ARD) as compared with placebo within the period of 14 days post injection up to 12 months post injection.