A Study to Assess the Safety, Tolerability, and Immunogenicity of RSVpreF in Older Adults in Korea

The goal of this clinical trial is to quantify the immune response in older Korean adults after a RSVpreF vaccination. It will also learn about the safety and tolerability of RSVpreF vaccination. The main questions it aims to answer are: What local reactions and systemic events do participants have after a RSVpreF vaccination? What medical problems do participants have after a RSVpreF vaccination? Researchers will compare RSVpreF to a placebo (a look-alike substance that contains no RSVpreF) to see if RSVpreF is safe and well tolerated. It will also examine the change in antibody levels (immune responses) before and after vaccination. Participants will: Receive the RSVpreF vaccination or a placebo injection once at Visit 1. Visit the clinic a month later for a checkup and tests. Receive a phone call 1 week after vaccination, and 2 months after vaccination, for health checks. Keep a diary of their symptoms for 7 days after vaccination.

This is a Phase 3, randomized, double-blinded, placebo-controlled, multicenter trial to describe the safety, tolerability, and immunogenicity of bivalent RSVpreF in adults 60 years of age and older in Korea. The study duration is approximately 2 months. 4 study visits are required and are comprised of 2 scheduled clinic visits and 2 scheduled telephone calls. Approximately 360 study-eligible participants will be randomized to receive either the 120-µg dose of RSVpreF or placebo in a 2:1 ratio. After screening and confirmation of eligibility, a prevaccination blood sample will be collected for immunogenicity assessments and a single dose of study intervention (RSVpreF or placebo) will be administered. Participants will report daily reactogenicity data using an electronic device for 7-days or until resolution. Participants will return approximately 1 month later for a follow-up blood draw for immunogenicity assessments and collection of safety information. A telephone follow-up visit will be conducted approximately 1 week after vaccination to review reactogenicity and approximately 2 months after vaccination to collect safety information. For all participants, adverse events (AEs) will be collected from informed consent through 1 month following study intervention administration. Serious adverse events (SAEs) newly diagnosed chronic medical conditions (NDCMCs), and adverse events of special interest (AESIs) will be collected from informed consent throughout study participation.