Respiratory Syncytial Virus (RSV) is a common virus that affects all human age groups and can cause a range of respiratory disease such as bronchitis and lower respiratory infections. These serious illnesses affect infants and adults who are older especially if they are over 65, have chronic heart or lung disease or have a weakened immune system. Vaccination against RSV has the potential to be a highly beneficial and effective approach to reduce RSV disease in older adults and pediatric populations, however there is no current vaccine approved for the prevention of RSV infections.~RSVpreF is being developed to prevent RSV-associated moderate to severe lower respiratory tract disease in adults 60 years of age and in infants by active immunization of pregnant women.~This study is an exploratory proof-of-concept to assess the safety, immunogenicity and efficacy of RSVpreF using a human challenge model. The RSV challenge model is developed to help understanding the RSV disease and assess new vaccines by testing them in participants deliberately infected with the virus.~In this study, approximately 62 (up to 72) participants will be vaccinated with the investigational RSVpreF to account for withdrawals between vaccination and challenge. Participants will be randomised 1:1 to receive RSVpreF or placebo.~The study will consist of a vaccination phase, quarantine phase and a follow-up phase.
In this randomised, placebo-controlled, double-blind Phase 2a study, healthy male and female participants 18-50 years of age will be given an investigational RSV vaccine (RSVpreF) and challenged with RSV one month later. The purpose of this research study is to assess the safety, immunogenicity and efficacy of RSVpreF using a human viral challenge model.