NCT07203365

RSV Immunogenicity Study in the Elderly (RISE)

Immunogenicity After a Prime Dose and Revaccination With Adjuvanted RSVPreF3 Vaccine in the Most Elderly and Frail Population - an Open-labeled Phase IIIb-trial

• Status: Recruiting
• Phase: Phase 3
• Study type: Interventional
• Enrollment: 65 (estimated)
• Sponsor: Karin Karin Loré · Academic / Other
• Sex: All
• Age: 60 Years
• Healthy volunteers: Accepted

Summary

Respiratory syncytial virus (RSV) is a common cause of respiratory tract infections leading to hospitalizations in infants and in elderly. Arexvy is an approved vaccine for the prevention of RSV infection, however, data on its efficacy in individuals aged 80 years and older remain limited. This study aims to evaluate potential differences in immune responses to Arexvy vaccination between adults aged ≥80 years and those aged 60-65 years.

Detailed description

Respiratory syncytial virus (RSV) is a common cause of respiratory tract infections that frequently lead to hospitalization, particularly in infants and older adults. The virus relies on two surface glycoproteins, F and G, for cell fusion and attachment, respectively. Among these, the F protein is the primary target of neutralizing antibodies and a critical focus in RSV vaccine development. RSV spreads through contaminated nasal secretions via large droplets, primarily transmitted through close human contact or contaminated surfaces. Notably, RSV infection does not confer lasting immunity, and the disease imposes a significant burden on healthcare systems, especially among infants and older adults-particularly those over 75 or with underlying health conditions. Despite more than half a century of research and a considerable global need, progress in RSV vaccine development has been slow. A key challenge has been inducing antibody (Ab) responses that are sufficiently specific, broad, and long-lasting to provide effective protection. However, in recent years, major strides have been made: two RSV vaccines were approved in 2023, and one in 2024, in both Europe and the United States, for the prevention of lower respiratory tract disease (LRTD) in individuals aged 60 years and older, as well as adults 50-59 years old at increased risk for RSV. Arexvy, developed and manufactured by GSK, is an adjuvanted RSV vaccine based on the prefusion-stabilized F protein. Its formulation includes the AS01E adjuvant, selected based on prior clinical data. A single dose of Arexvy has demonstrated efficacy against LRTD across three RSV seasons in adults aged 60 and above. The vaccine has shown an acceptable safety and reactogenicity profile. Despite these advancements, there remains limited data on vaccine responses in individuals aged 80 and above, as well as in frail populations, due to their underrepresentation in ongoing clinical trials. While some immunogenicity data are available, a substantial knowledge gap persists regarding the immune responses elicited by Arexvy in this highly vulnerable group who are disproportionately affected by severe RSV infections. Therefore, studying possible differences in the immune response induced upon vaccination with Arexvy between elderly above 80 years of age and younger individuals (60 65 years old) will provide key insights for defining future vaccination strategies in these populations.

Conditions

• RSV Immunisation

Interventions

Type	Name	Description
BIOLOGICAL	This study examines immune response differences Arexvy between individuals aged 80+ and adults aged 60-65	The RSV vaccine (Arexvy) has demonstrated efficacy against LRTD over three RSV seasons in individuals aged 60 and older, with an acceptable safety and reactogenicity profile. However, data on vaccine responses in individuals aged 80 and older, including frail individuals, remains limited. This population is particularly affected by severe RSV infections, highlighting the need for further investigation to address these gaps.

Timeline

• Start date: 2025-08-25
• Primary completion: 2027-05-31
• Completion: 2029-05-31
• First posted: 2025-10-02
• Last updated: 2025-10-02

Locations

2 sites across 1 country: Sweden