N/A N=20 Basic Science

Novel Mucosal Correlates Of RSV Protection In Older Adults

Respiratory Tract Infections

Bottom Line

View on ClinicalTrials.gov: NCT06274619 ↗

Enrolled (actual)

Serious AEs

0.0%

Results posted

May 2026

Primary outcome: Primary: Number of Solicited and Unsolicited Adverse Events (AEs) — 17 adverse events

Study Design & Population

Study type: Interventional
Phase: N/A
Interventions: RSV A Memphis 37 (Biological)
Age: Older Adult · 65+ yrs
Sex: All
Sponsor: Imperial College London
Primary completion: Apr 2025

Outcome Measures

Outcome	Result	p-value
PRIMARY Number of Solicited and Unsolicited Adverse Events (AEs)	17	—
PRIMARY Infection Rate	12; 8	—
SECONDARY Nasal Viral Load	—	—
SECONDARY Antibody Levels by Serum Neutralisation Assay	—	—
SECONDARY Antibody Levels by ELISA	—	—

Summary

Respiratory syncytial virus (RSV) is one of the most common causes of chest infection worldwide. Despite this, it remains an underappreciated health problem, with the first effective RSV vaccines only approved by the FDA in May 2023 and unlikely to be widely available for some time. Although RSV infection is most frequent in young children, most deaths occur in older adults, particularly in those with underlying heart and lung disease. This is believed to be due in part to the ageing immune system's reduced ability to protect against infection and symptomatic disease. However, little is known about the way human immune responses to RSV infection in older individuals differ from those of younger people. Further understanding of the mechanisms underlying immunity and potential impairments in these higher-risk people are therefore necessary. This project aims to study the factors that influence whether or not older people develop symptomatic RSV disease in healthy older volunteers after being given an RSV-induced common cold. Samples will be taken from the blood and nose in order to identify changes in the immune system associated with susceptibility or protection in older adults. Participants will be carefully screened to ensure there are no underlying health problems that might make them more at risk of severe disease and will be monitored closely throughout the course of infection. It is anticipated that differences in immune markers in the nose and/or blood of healthy older people will predict whether or not such individuals become infected or develop symptoms. By analysing the networks of genes that are switched on and off, the aim is to identify the pathways in the immune system responsible for these differences, to ultimately develop improved diagnostic tests, vaccines and treatments.

Eligibility Criteria

Inclusion Criteria

Healthy persons aged 65 to 75 years, able to give informed consent
Non-smokers or ex-smokers with a pack year history of 10 or less
Spirometry within the normal range for age and height (+/- 15%)
Forced Expiratory Volume / Forced Vital Capacity (FEV1/FVC) >70% without bronchodilator
Vaccination against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) at the minimum of 4 weeks prior to screening

Exclusion Criteria

Chronic respiratory disease (asthma, chronic obstructive pulmonary disease, rhinitis, sinusitis) in adulthood
Inhaled bronchodilator or steroid use within the last 12 months
Habitual use of any medication or other product (prescription or over the counter) for symptoms of rhinitis or nasal congestion within the last 3 months
Acute upper respiratory infection (URI or sinusitis) in the past 6 weeks
Participants with allergic symptoms present at baseline
Clinically relevant abnormality on chest X-ray
Those in close domestic contact (i.e. sharing a household with, caring for, or daily face to face contact) with children under 3 years, clinically vulnerable and/or immunosuppressed persons, or those with chronic respiratory disease
Participants with known or suspected immune deficiency
Receipt of systemic glucocorticoids (in a dose ≥ 5 mg prednisone daily or equivalent) within one month, or any other cytotoxic or immunosuppressive drug within 6 months prior to challenge
Known Immunoglobulin A (IgA) deficiency, immotile cilia syndrome, or Kartagener's syndrome
History of frequent nose bleeds
Any significant medical condition or prescribed drug deemed by a study doctor to make the participant unsuitable for the study
Recent or current use of recreational drugs, confirmed by a positive urine drug screen
History of difficult blood draw, syncope or poor tolerance of sampling procedures

View full record on ClinicalTrials.gov →

Data sourced from ClinicalTrials.gov (NCT06274619). Outcome figures and adverse-event rates are extracted automatically from the registry's posted results and are provided for clinician reference, not as a substitute for the primary publication.