Efficacy Study: This randomized, double-blinded, placebo-controlled Phase 3 study is designed to assess the safety, immunogenicity, and efficacy of a single dose of RSVpreF in the prevention of LRTI-RSV in adults:
- At a dose of 120µg.
- In adults 60 years of age and older.
- The duration of the study for each participant will be up to approximately 24 months.
- The study will be conducted in the United States, Canada, Netherlands, Finland, Argentina, Japan and South Africa.
Substudy A: This study is an extension of the efficacy study and was designed to evaluate the safety and immunogenicity of a second dose of RSVpreF when administered after a dosing interval of approximately 2 years:
- At a dose of 120µg (as studied in the Phase 3 Efficacy Study)
- Blood samples will be collected for antibody testing.
- The duration of the study for each participant will be up to approximately 18 months.
- The study will be conducted in the United States and Argentina.
Substudy B: This study was designed to evaluate the safety and immunogenicity of a second dose of RSVpreF when administered after a dosing interval of approximately 1 year:
- At a dose of 120µg (as studied in the Phase 3 Efficacy Study)
- Blood samples will be collected for antibody testing.
- The duration of the study for each participant will be up to approximately 18 months.
- The study will be conducted in Argentina.
Substudy C: This study was designed to evaluate the safety and immunogenicity of a second dose of RSVpreF when administered after a dosing interval of either 3 or 4 years:
- At a dose of 120µg (as studied in the Phase 3 Efficacy Study)
- Participants will receive either placebo or a second dose of RSVpreF approximately 3 or 4 years after receiving the initial dose of RSVpreF in the main efficacy study.
- Blood samples will be collected for antibody testing.
- The duration of the study for each participant will be up to approximately 18 months.
- The study will be conducted in the United States and Canada.