N/A N=75 Basic Science

Cell Mediated Immunity Against RSV and Influenza in a Human Experimental Challenge

Respiratory Syncytial Virus Infections · Influenza, Human

Bottom Line

View on ClinicalTrials.gov: NCT02755948 ↗

Enrolled (actual)

Serious AEs

0.0%

Results posted

Dec 2024

Primary outcome: Primary: Total Symptom Score — 29.25; 17.50; 11.00; 13.00 score on a scale

Study Design & Population

Study type: Interventional
Phase: N/A
Interventions: RSV A Memphis 37 (Biological); Influenza A/California/04/2009-likw (H1N1) (Biological); Influenza A/Belgium/4217/2015 (H3N2) (Biological)
Age: Adult · 18+ yrs
Sex: All
Sponsor: Imperial College London
Primary completion: Feb 2020

Outcome Measures

Outcome	Result	p-value
PRIMARY Total Symptom Score	29.25; 17.50; 11.00; 13.00; 0; 1	—
SECONDARY Frequency of T Cells in Blood by Flow Cytometry	0.79; 3.81; 4.13; 0.49; 0.985; 1.18	—
SECONDARY Frequency of T Cells in Respiratory Tract by Flow Cytometry	2.21; 81.15; 4.36; 0.65; 0.412	—
SECONDARY Viral Load	18.24; 5.85; 26.40; 0; 0; 0	—
SECONDARY Frequency of T Cells in Blood by Enzyme-linked Immunospot (ELISpot)	778.30; 161; 159.20; 29	—

Summary

Respiratory viruses including influenza and respiratory syncytial virus (RSV) are among the most important causes of severe disease globally, infecting everyone repeatedly throughout life. Understanding of how to prevent infection is incomplete but boosting immunity with vaccines remains the best strategy. T cells have been shown in animals to be essential for clearing respiratory viral infection and are likely to be helpful if stimulated by vaccines. However, where these cells originate from and how they develop in the human lung are still unclear. The investigators will inoculate volunteers with influenza or RSV to examine the relationship between T cells in their blood and lungs and the outcome of infection. By tracking these specialised cells, the investigators aim to develop a better understanding of how they are generated in order to harness them with future vaccines.

Eligibility Criteria

Inclusion Criteria

Healthy persons aged 18 to 55 years, able to give informed consent

Exclusion Criteria

Chronic respiratory disease (asthma, chronic obstructive pulmonary disease, rhinitis, sinusitis) in adulthood
Inhaled bronchodilator or steroid use within the last 12 months
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
Smoking in the past 6 months OR >5 pack-year lifetime history
Subjects with allergic symptoms present at baseline
Clinically relevant abnormality on chest X-ray
Any ECG abnormality
Those in close domestic contact (i.e. sharing a household with, caring for, or daily face to face contact) with children under 3 years, the elderly (>65 years), immunosuppressed persons, or those with chronic respiratory disease
Subjects 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 deficiency, immotile cilia syndrome, or Kartagener's syndrome
History of frequent nose bleeds
Any significant medical condition or prescribed drug deemed by the study doctor to make the participant unsuitable for the study
Pregnant or breastfeeding women
Positive urine drug screen
Detectable baseline haemagglutination inhibition titres against influenza challenge strains
Influenza arm only: history of hypersensitivity to eggs, egg proteins, gentamicin, gelatin or arginine, or with life-threatening reactions to previous influenza vaccinations

View full record on ClinicalTrials.gov →

Data sourced from ClinicalTrials.gov (NCT02755948). 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.