Evergreen is a Phase 3 study that will enroll up to 27,500 participants to demonstrate the efficacy of the active Ad26.RSV.preF-based study vaccine in the prevention of Reverse Transcription Polymerase Chain Reaction (RT-PCR) confirmed Respiratory Syncytial Virus (RSV)-mediated Lower Respiratory Tract Disease (LRTD) when compared to placebo in adults aged 60 years and above.