A Study on the Immune Response and Safety of Vaccine Against Respiratory Syncytial Virus (RSV) Given to Adults 18 to 49 Years of Age at Increased Risk for Respiratory Syncytial Virus Disease, Compared to Older Adults 60 Years of Age and Above

A Phase 3b, Open-label Study to Evaluate the Non-inferiority of the Immune Response and to Evaluate the Safety of the RSVPreF3 OA Investigational Vaccine in Adults 18-49 Years of Age at Increased Risk for Respiratory Syncytial Virus Disease, Compared to Older Adults >=60 Years of Age

The aim of this study is to demonstrate the immune response and to evaluate the safety of the RSVPreF3 OA investigational vaccine in non-immunocompromised adults 18-49 years of age (YOA), who are at increased risk (AIR) for RSV disease, compared to older adults (OA) 60 YOA and above.

Study Overview

• Status: Completed
• Conditions: Respiratory Syncytial Virus Infections
• Intervention / Treatment: Biological: RSVPreF3 OA investigational vaccine

• Study Type: Interventional
• Enrollment (Actual): 1459
• Phase: Phase 3

Contacts and Locations

Study Locations

• Australia
  • New South Wales
    • Coffs Harbour, New South Wales, Australia, 2450
      • GSK Investigational Site
    • Sydney, New South Wales, Australia, 2010
      • GSK Investigational Site
    • Sydney, New South Wales, Australia, 2065
      • GSK Investigational Site
  • Queensland
    • Fortitude Valley, Queensland, Australia, 4006
      • GSK Investigational Site
    • Tarragindi, Queensland, Australia, 4121
      • GSK Investigational Site
  • Victoria
    • Melbourne, Victoria, Australia, 3051
      • GSK Investigational Site
    • St Albans, Victoria, Australia, 3021
      • GSK Investigational Site
• Canada
  • British Columbia
    • New Westminster, British Columbia, Canada, V3L 3W4
      • GSK Investigational Site
    • Victoria, British Columbia, Canada, V8V 4A1
      • GSK Investigational Site
  • Nova Scotia
    • Truro, Nova Scotia, Canada, B2N 1L2
      • GSK Investigational Site
  • Ontario
    • Greater Sudbury, Ontario, Canada, P3C 1X3
      • GSK Investigational Site
    • Guelph, Ontario, Canada, N1G 0B4
      • GSK Investigational Site
    • London-Ontario, Ontario, Canada, N5W 6A2
      • GSK Investigational Site
    • Toronto, Ontario, Canada, M4G 3E8
      • GSK Investigational Site
  • Quebec
    • Québec, Quebec, Canada, G1N 4V3
      • GSK Investigational Site
    • Québec, Quebec, Canada, G1V 4G2
      • GSK Investigational Site
    • Québec, Quebec, Canada, G1V 4W2
      • GSK Investigational Site
    • Saint-Charles-Borromée, Quebec, Canada, J6E 2B4
      • GSK Investigational Site
    • Sherbrooke, Quebec, Canada, J1J 2G2
      • GSK Investigational Site
• Germany
  • Berlin, Germany, 10117
    • GSK Investigational Site
  • Berlin, Germany, 10787
    • GSK Investigational Site
  • Berlin, Germany, 13347
    • GSK Investigational Site
  • Essen, Germany, 45355
    • GSK Investigational Site
  • Mainz, Germany, 55116
    • GSK Investigational Site
  • Wallerfing, Germany, 94574
    • GSK Investigational Site
  • Witten, Germany, 58455
    • GSK Investigational Site
  • Würzburg, Germany, 97070
    • GSK Investigational Site
  • Baden-Wurttemberg
    • Weinheim, Baden-Wurttemberg, Germany, 69469
      • GSK Investigational Site
• Japan
  • Ibaraki, Japan, 300-0062
    • GSK Investigational Site
  • Kanagawa, Japan, 211-0041
    • GSK Investigational Site
  • Tokyo, Japan, 155-0031
    • GSK Investigational Site
  • Tokyo, Japan, 180-0022
    • GSK Investigational Site
• South Africa
  • Cape Town, South Africa, 7530
    • GSK Investigational Site
  • Cape Town, South Africa, 7700
    • GSK Investigational Site
  • Johannesburg, South Africa, 2113
    • GSK Investigational Site
  • Reiger Park, South Africa, 1459
    • GSK Investigational Site
• United States
  • Arizona
    • Glendale, Arizona, United States, 85308
      • GSK Investigational Site
    • Phoenix, Arizona, United States, 85284
      • GSK Investigational Site
  • California
    • North Hollywood, California, United States, 91606-3287
      • GSK Investigational Site
    • Oakland, California, United States, 94610
      • GSK Investigational Site
    • Walnut Creek, California, United States, 94598
      • GSK Investigational Site
  • Florida
    • Hialeah, Florida, United States, 33012
      • GSK Investigational Site
    • North Miami, Florida, United States, 33173
      • GSK Investigational Site
    • Orlando, Florida, United States, 32806
      • GSK Investigational Site
  • Kentucky
    • Lexington, Kentucky, United States, 40509
      • GSK Investigational Site
  • Maryland
    • Silver Spring, Maryland, United States, 20904
      • GSK Investigational Site
  • New York
    • Rochester, New York, United States, 14609
      • GSK Investigational Site
  • Oklahoma
    • Oklahoma City, Oklahoma, United States, 73111
      • GSK Investigational Site
  • Tennessee
    • Knoxville, Tennessee, United States, 37909
      • GSK Investigational Site
  • Texas
    • DeSoto, Texas, United States, 75115
      • GSK Investigational Site
  • Virginia
    • Charlottesville, Virginia, United States, 22911
      • GSK Investigational Site
  • Washington
    • Wenatchee, Washington, United States, 98801
      • GSK Investigational Site

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• Participants and/or participant's parent(s)/ Legally acceptable representative (LAR) who, in the opinion of the investigator, can and will comply with the requirements of the protocol (e.g., completion of the eDiary, attend study site visits, ability to access and utilize a phone or other electronic communications).
• Written or witnessed informed consent obtained from the participant/participant's parent(s)/LAR(s) (participant must be able to understand the informed consent) prior to performance of any study-specific procedure.

Written informed assent obtained from the participant (participant must be able to understand the informed assent) if he/she is less than the legal age prior to performance of any study-specific procedure.

Specific inclusion criteria for all participants in Cohort 1 and Cohort 3 (RSV-A-AIR Group) • A male or female participant 18-49 YOA at the time of the study intervention administration.

• Participants should be diagnosed with at least 1 of the following medical conditions if considered medically stable by the investigator:

  • Chronic cardiopulmonary disease resulting in activity restricting symptoms or use of long term medication:

    o Chronic obstructive pulmonary disease (COPD)

    o Asthma

    o Cystic fibrosis

    o Other chronic respiratory diseases: lung fibrosis, restrictive lung disease, interstitial lung disease, emphysema or bronchiectasis

    o Chronic heart failure:

    o Pre-existing Coronary Artery Disease (CAD) (CAD not otherwise specified)

    • Cardiac arrhythmia
  • Diabetes mellitus: types 1 or 2 with active treatment for the past 6 months

  • Other diseases at increased risk for RSV disease:

    • Chronic kidney disease
    • Chronic moderate to severe liver disease
    • Neurologic or neuromuscular conditions
• Female participants of non-childbearing potential may be enrolled in the study. Non-childbearing potential is defined as premenarche, hysterectomy, bilateral oophorectomy, bilateral salpingectomy or post-menopause.

• Female participants of childbearing potential may be enrolled in the study, if the participant:

  • has practiced adequate contraception from 1 month prior to study intervention administration, and
  • has a negative pregnancy test on the day of study prior to intervention administration, and
  • has agreed to continue adequate contraception for at least 1 month after completion of the study intervention administration.

Specific inclusion criteria for all participants in Cohort 2 (RSV-OA Group):

• A male or female participant >=60 YOA at the time of the study intervention administration.

Participants with chronic stable medical conditions with or without specific treatment, such as diabetes, hypertension or cardiac disease are allowed to participate in this study if considered medically stable by the investigator.

• Participants living in the general community or in an assisted-living facility that provides minimal assistance, such that the participant is primarily responsible for self-care and activities of daily living.

Exclusion Criteria:

Medical conditions

• Any confirmed or suspected immunosuppressive or immunodeficient condition resulting from disease (e.g., current malignancy, human immunodeficiency virus) or immunosuppressive/cytotoxic therapy (e.g., medication used during cancer chemotherapy, organ transplantation, or to treat autoimmune disorders), based on medical history and physical examination (no laboratory testing required).
• History of any reaction or hypersensitivity likely to be exacerbated by any component of the study intervention.
• Unstable chronic illness.
• Any history of dementia or any medical condition that moderately or severely impairs cognition.
• Recurrent or uncontrolled neurological disorders or seizures. Participants with medically controlled active or chronic neurological diseases can be enrolled in the study as per investigator assessment, provided that their condition will allow them to comply with the requirements of the protocol (e.g., completion of the diary cards, attend study site visits). Study participants may decide to assign a caregiver to help them complete the study procedures.
• Significant underlying illness that in the opinion of the investigator would be expected to prevent completion of the study (e.g., life-threatening disease).
• Any medical condition that in the judgment of the investigator would make intramuscular injection unsafe.
• Any other clinical condition that, in the opinion of the investigator, might pose additional risk to the participant due to participation in the study.

Prior/Concomitant therapy

• Use of any investigational or non-registered product (drug, vaccine, or medical device) other than the study intervention during the period beginning 30 days before the dose of study intervention (Day -29 to Day 1), or planned use during the study period (up to Visit 3, Month 6).
• Planned or actual administration of a vaccine not foreseen by the study protocol in the period starting 30 days before and ending 30 days after the dose of study intervention administration, with the exception of inactivated, subunit and split influenza vaccines or COVID-19 vaccines which can be administered up to 14 days before or from 14 days after the study intervention administration.
• Previous vaccination with any RSV vaccine, including investigational RSV vaccines.

• Chronic administration of immune-modifying drugs (defined as more than 14 consecutive days in total) and/or administration of long-acting immune-modifying treatments or planned administration at any time up to the End-of-study (EOS).

  • Up to 3 months prior to the study intervention administration:

    • For corticosteroids, this will mean prednisone >=20 mg/day, or equivalent. Inhaled, topical and intra-articular steroids are allowed
    • Administration of immunoglobulins and/or any blood products or plasma derivatives
  • Up to 6 months prior to study intervention administration: long-acting immune-modifying drugs including among others immunotherapy (e.g., Tumor Necrosis Factor (TNF)-inhibitors), monoclonal antibodies, antitumoral medication.

Prior/Concurrent clinical study experience

• Concurrently participating in another clinical study, at any time during the study period, in which the participant has been or will be exposed to an investigational or a non-investigational vaccine/product (drug or invasive medical device).

Other exclusions:

Other exclusions for all participants:

• History of chronic alcohol consumption and/or drug abuse as deemed by the investigator to render the potential participant unable/unlikely to provide accurate safety reports or comply with study procedures.
• Bedridden participants.
• Planned move during the study period that will prohibit participating in the study until study end.
• Participation of any study personnel or their immediate dependents, family, or household members.

Other exclusions for Cohort 1 and Cohort 3:

• Pregnant or lactating female participant.
• Female planning to become pregnant or planning to discontinue contraceptive precautions within 1 month after study intervention administration.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Non-Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Part A: RSV-A-AIR Group; Adult (A) participants, 18-49 YOA, at increased risk (AIR) for RSV disease, received a single dose of RSVPreF3 OA investigational vaccine at Day 1. Participants in this group were considered for all study analyses, as per protocol.	Biological: RSVPreF3 OA investigational vaccine; 1 dose of RSVPreF3 OA investigational vaccine is administered intramuscularly on Day 1.
Active Comparator: Part A: RSV-OA Group; Older adults (OA) participants, ≥60 YOA, received a single dose of RSVPreF3 OA investigational vaccine at Day 1.	Biological: RSVPreF3 OA investigational vaccine; 1 dose of RSVPreF3 OA investigational vaccine is administered intramuscularly on Day 1.
Experimental: Part B: RSV-A-AIR Group; Adult participants, 18-49 YOA, AIR for RSV disease, received a single dose of RSVPreF3 OA investigational vaccine at Day 1. Participants in this group were considered only for Participant flow, Baseline Characteristics and all safety analyses, as per protocol.	Biological: RSVPreF3 OA investigational vaccine; 1 dose of RSVPreF3 OA investigational vaccine is administered intramuscularly on Day 1.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Part A: RSV-A Neutralizing Titers Expressed as Group Geometric Mean Titers (GMTs)	RSV-A neutralizing titers are given as group GMTs and are expressed as Estimated dilution 60 (ED60)	At Day 31
Part A: Percentage of Participants With Seroresponse Rate (SRR) in RSV-A Neutralizing Titers	SRR is defined as the percentage of participants having a fold increase in neutralizing titers (1 month post-study intervention administration over pre-study intervention administration) ≥4. RSV-A neutralizing titers are expressed as ED60.	Day 31 compared with baseline (Day 1)
Part A: RSV-B Neutralizing Titers Expressed as Group GMTs	RSV-B neutralizing titers are given as group GMTs and are expressed as ED60.	At Day 31
Part A: Percentage of Participants With SRR in RSV-B Neutralizing Titers	SRR is defined as the percentage of participants having a fold increase in neutralizing titers (1-month post-study intervention administration over pre-study intervention administration) ≥ 4. RSV-B neutralizing titers are expressed as ED60.	Day 31 compared with baseline (Day 1)

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Part A and B: Number of Participants Reporting Any Solicited Administration Site Events	Assessed solicited administration site events were pain, redness (erythema) and swelling at administration site. Any = occurrence of the symptom regardless of intensity grade.	Day 1 (post dose) to Day 4
Part A and B: Number of Participants Reporting Any Solicited Systemic Events	Assessed solicited systemic events were fever (pyrexia), headache, myalgia (muscle pain), arthralgia (joint pain) and fatigue (tiredness). Fever was defined as temperature ≥38.0 degrees Celsius (°C), regardless of the location of measurement. The route for measuring temperature could be oral or axillary. Any = occurrence of the symptom regardless of intensity grade.	Day 1 (post dose) to Day 4
Part A and B: Number of Participants Reporting Unsolicited Adverse Events (AEs)	An unsolicited AE wass an AE that was either not included in the list of solicited events or could be included in the list of solicited events but with an onset outside the specified period of follow-up for solicited events. Unsolicited AEs included both serious and non-serious AEs.	Day 1 (post dose) to Day 30
Part A and B: Number of Participants Reporting Any Serious Adverse Events (SAEs), Related SAEs and Fatal SAEs	An SAE is any untoward medical occurrence that results in death, is life-threatening, requires hospitalization or prolongation of existing hospitalization, results in disability/incapacity, is a congenital anomaly/birth defect in the offspring of a study participant, is considered or defined as an important medical event, or abnormal pregnancy outcomes. Any SAE = occurrence of the SAE regardless of the intensity grade or relation to study vaccination. Related SAE = SAE assessed by the investigator as related to the study vaccination. Fatal SAE = occurrence of a fatal SAE regardless of relation to study vaccination.	Throughout the study period (Day 1 to Month 6)
Part A and B: Number of Participants Reporting Any Adverse Events of Special Interest (AESIs)	AESIs assessed were potential immune-mediated diseases (pIMDs) and atrial fibrillation (AF). pIMDs were a subset of AESIs that included autoimmune diseases and other inflammatory and/or neurologic disorders of interest which may or may not have an autoimmune etiology. AEs of AF were considered as AESI.	Throughout the study period (Day 1 to Month 6)
Part A: RSV-A Neutralizing Titers Expressed as GMTs	RSV-A neutralizing titers are given as GMTs and are expressed as ED60.	At Day 1 (pre-dose), at Month 1 and Month 6
Part A: RSV-B Neutralizing Titers Expressed as GMTs	RSV-B neutralizing titers are given as GMTs and are expressed as ED60.	At Day 1 (pre-dose), at Month 1 and Month 6

Collaborators and Investigators

• Sponsor: GlaxoSmithKline

Study record dates

Study Major Dates

• Study Start (Actual): April 29, 2024
• Primary Completion (Actual): July 29, 2024
• Study Completion (Actual): March 18, 2025

Study Registration Dates

• First Submitted: April 24, 2024
• First Submitted That Met QC Criteria: April 24, 2024
• First Posted (Actual): April 29, 2024

Study Record Updates

• Last Update Posted (Estimated): September 25, 2025
• Last Update Submitted That Met QC Criteria: September 9, 2025
• Last Verified: September 1, 2025

More Information

Terms related to this study

• Keywords: Safety; Older Adults; Immunogenicity; Respiratory Syncytial Virus (RSV); Humoral immune response; Non-inferiority; At increased risk (AIR)
• Additional Relevant MeSH Terms: Infections; RNA Virus Infections; Virus Diseases; Pneumovirus Infections; Paramyxoviridae Infections; Mononegavirales Infections; Respiratory Syncytial Virus Infections
• Other Study ID Numbers: 222253; 2023-510190-34-00 (Other Identifier: EU CTR Number)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: GSK will assess requests from qualified researchers for anonymized individual patient-level data and related study documents. Data sharing is subject to certain criteria, conditions, and exceptions. For further information, refer tohttps://www.gsk-studyregister.com/About_GSK_Patient_Level_Data_Sharing_Final_13July2023.pdf
• IPD Sharing Time Frame: Anonymized IPD will be made available within 6 months of publication of primary, key secondary and safety results for studies in product with approved indication(s) or terminated asset(s) across all indications.
• IPD Sharing Access Criteria: Anonymized IPD is shared with researchers whose proposals are approved by an Independent Review Panel and after a Data Sharing Agreement is in place. Access is provided for an initial period of 12 months but an extension may be granted, when justified, for up to 6 months.
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL; SAP; ICF; CSR

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No