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RSVCHIRP02NCT07713628

Immune Reponses to RSV B Challenge in Older Adults (A Controlled Human Infection Study With RSV in Older People-02)

A study testing RSV B in people with RSV, run by Imperial College London.

Not yet recruiting

Opening soon. The study is approved but enrolment has not started yet. Sites may already take enquiries.

Sites and contacts
Official record
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Trial summary

This is a human challenge sequential cohort study involving healthy, non-smoking older adults aged 65-75 years. We aim to enrol 20 participants. There will be a sentinel cohort of 6 participants at the beginning of the study (Group 1). Read more about this study

Who is it for?
Ages 65 to 75 yearsHealthy volunteers can take part
Conditions the study is for
RSV
What is being tested?
RSV B
Could I receive a placebo?
No, everyone receives an active treatment
How many people
20 participants
Where
No sites listed yet
Study dates
1 Aug 2026to 30 May 2028
Phase
Interventional
Are there results?
Not yet: the study is under way

Key requirements

Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.

  • Ages 65 to 75 years
  • All sexes
  • Healthy volunteers accepted
  • Older adult

Who may be able to join

  • Aged between 65 to 75years (inclusive) at Day 0.
  • Willing and able to commit to participation in the study.
  • Adequate understanding of the study, the procedures involved, and able to provide written informed consent prior to any study procedures.
  • In good health with no history of clinically significant medical conditions (as described in exclusion criteria) that would interfere with participant safety. A forced expiratory volume in 1 second (FEV1) and a forced vital capacity (FVC) <80% of predicted value calculated using ATS/ERS guidance.

Who cannot join

  • Any significant medical condition or prescribed drug deemed by the Investigator to deem the participant unsuitable for the study.
  • History or evidence of any clinically significant or currently active:
  • Cardiovascular, thromboembolic or cerebrovascular disease.
  • Chronic respiratory disease (e.g. asthma, COPD, rhinitis, sinusitis, reactive airway disease, pulmonary hypertension or a chronic lung condition) in adulthood (a history of childhood asthma without respiratory disease in adulthood may be accepted at the PIs discretion).
  • Significant or severe wheeze, or respiratory symptoms (including wheeze) which has ever resulted in hospitalisation.
  • Known bronchial hyperactivity to viruses.
Show all 50Show fewer
  • Diabetes mellitus.
  • Migraine with associated neurological symptoms such as hemiplegia or vision loss. Cluster headache/migraine or prophylactic treatment for migraine.
  • History or evidence of autoimmune disease or known/suspected immunodeficiency of any cause, including asplenia or history of recurrent severe infections.
  • Immunosuppression of any type.
  • Known IgA deficiency, immotile cilia syndrome, or Kartagener's syndrome.
  • Known coagulation disorder or anticoagulant therapy.
  • Psychiatric illness including participants with a history of depression and/or anxiety with associated severe psychiatric comorbidities, for example psychosis. Consider exclusion in the following cases: Participants with history of anxiety-related symptoms of any severity within the last 2 years if the Generalized Anxiety Disorder-7 score is ≥4; Participants with a history of depression of any severity within the last 2 years if the Patient Health Questionnaire-9 score is ≥4; . Severe claustrophobia
  • Other major disease that, in the opinion of the Investigator, could interfere with a participant completing the study and necessary investigations.
  • Concurrent serious illness including history of malignancy that could interfere with the aims of the study or a participant completing the study.
  • Permissible stable conditions that are well controlled might not be exclusionary and will be assessed by the PI on a case-by-case basis. These include, but will not be limited to: well controlled Hypertension, Sensitive Bladder, Hiatus Hernia, Vitamin D Deficiency, Diverticulitis, Renal Calculi, Depression (well managed), Perioral Dermatitis, Hypercholesterolemia (diet or well medically controlled), Macular Degeneration, Mild Arthritis.
  • Any significant abnormality altering the anatomy or function of the nose or nasopharynx in a substantial way, including nasopharyngeal malignancy, arterio-venous malformation, or undiagnosed nasopharyngeal mass.
  • A history of clinically significant epistaxis (large nosebleeds) within 3 months of Day 0.
  • Nasal or sinus surgery within 3 months of Day 0.
  • Any anatomic or neurologic abnormality impairing the gag reflex or associated with increased risk of aspiration.
  • 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 Day 0.
  • A history of inhaled bronchodilator or inhaled steroid use within the prior 12 months to Day -14.
  • Receipt of any vaccine within 30 days of Day -14 or planned during the study period, until the last follow-up visit (Day 90).
  • Participation in an investigational drug or device study within 3 months prior to Day 0.
  • Receipt of blood or blood products, or loss (including blood donations) of 550 mL or more of blood during the 6 months prior to Day -14.
  • History of difficult blood draw, syncope or poor tolerance of sampling procedures as assessed by clinical study team.
  • History of anaphylaxis and/or a history of severe allergic reaction or significant intolerance to any food or drug, as assessed by the PI.
  • Allergic symptoms present at baseline (at screening, day -14 or day 0).
  • Clinically active rhinitis (including hay fever) or history of moderate to severe rhinitis, or history of seasonal allergic rhinitis likely to be active at the time of inclusion into the study and/or requiring regular nasal corticosteroids on an at least weekly basis, within 30 days of enrolment.
  • Habitual use of any medication or other product (prescription or over the counter) for symptoms of rhinitis or nasal congestion the 3 months prior to Day -14.
  • Receipt of RSV vaccine at any time or planned RSV vaccination in the 3 months following inoculation.
  • Virologically confirmed RSV infection within 6 months of Day 0.
  • Prior inoculation with a virus from the same virus family (Pneumoviridiae) as the challenge virus.
  • Prior participation in another controlled human infection study with a respiratory virus in the preceding 6 months taken from the date of viral challenge in the previous study to the date of expected viral challenge in this study.
  • Acute upper respiratory infection (URI or sinusitis) in the 6 weeks prior to Day-14 baseline visit.
  • Presence of cold-like symptoms and/or fever (defined as participant presenting with a temperature reading of >37.9ºC) on Day -14, Day -1 or Day 0.
  • A respiratory PCR test that is indicative of Influenza, RSV or other respiratory virus infection, including asymptomatic infections, determined by a test on admission to quarantine (Day -1).
  • Clinically relevant abnormality on chest X-ray.
  • A total body weight of ≤ 50kg and a Body Mass Index (BMI) ≤18 kg/m2 or ≥28 kg/m2.
  • The upper limit of BMI may be increased to ≤ 30kg/m2 at the PI's discretion, in the case of physically fit muscular individual or other variation of normal).
  • Any abnormal finding on screening safety blood tests deemed to be clinically significant by the Investigator including positive HIV, active/chronic hepatitis B or C test.
  • Any ECG abnormality deemed to be clinically significant by the Investigator.
  • Significant history or presence of drug or alcohol misuse.
  • Participants will be required to have a negative urine drug test at screening. If positive, this will be exclusionary.
  • Current use of more than 21 units alcohol per week, drug abuse, or regular use of sedatives, hypnotics, tranquilisers or any other addictive agent are exclusionary.
  • Current use of any recreational drugs, including injected, taken through the nose or inhaled route.
  • Regular smoking and/or vaping and/or using other nicotine-containing products in the past 3 months OR:
  • >5 pack-year lifetime history by self-report (5 pack years is equivalent to one pack of 20 cigarettes per day for 5 years).
  • Participants will be required to have a negative urine cotinine test at screening. If positive, this will be exclusionary.
  • Those in close domestic contact (i.e. sharing a household with, caring for, or daily face to face contact) with children under 4 years, clinically vulnerable and/or immunosuppressed persons, or those with chronic respiratory disease for 30 days after RSV B inoculation.

Trial locations and contacts

No sites are listed yet. Contact the study team or a site near you to ask about taking part.

Polly Fox-Sheehan, BSc, MSc contact

02033131282

polly.fox@imperial.ac.uk

About this study

Official title: CHIRP02 - Immune Reponses to RSV B Challenge in Older Adults (A Controlled Human Infection Study With RSV in Older People-02)

This is a human challenge sequential cohort study involving healthy, non-smoking older adults aged 65-75 years. We aim to enrol 20 participants. There will be a sentinel cohort of 6 participants at the beginning of the study (Group 1). If no pausing rules are met, the remaining 14 participants will be enrolled for a total of 20 enrolled participants (Group 2).

The study will consist of three main phases: (1) screening and baseline, (2) inoculation and quarantine, and (3) follow up.

Read more

All participants will attend a screening visit for a comprehensive health assessment to confirm eligibility.

If eligible, participants will take part in an inpatient stay in a quarantine unit, where they will be inoculated with 105 plaque-forming units of RSV B-I54 by intranasal drops. The inoculation dose has been determined in the earlier mentioned outpatient study of the same virus strain, in healthy young adults.

Due to the older age range and potentially increased risk of more severe disease, participants will remain within the quarantine unit for 10-days post inoculation and will be closely monitored by clinical review and self-completed symptom diaries. Participants will undergo daily sample collection and will remain in quarantine until the discharge criteria are met at Day 10.

After discharge, participants will attend follow-up visits at Day 14, Day 28, and Day 90.

Participants in Group 2 will have an additional baseline visit at Day -14 where blood, respiratory (nose and throat) and lower airway (bronchoscopy) samples will be collected. Group 2 participants will also undergo a second bronchoscopy during the inpatient period and the third and final bronchoscopy at Day 28.

Clinical outcomes will be determined by symptomatology and viral detection in nasal lavage using quantitative PCR. Based on the first-in-human RSV B characterisation study and recent elderly RSV A challenge data, we anticipate approximately 74% attack rate, with a range of mild-moderate symptoms in the infected individuals. Symptoms typically commence 3 days post-inoculation and worsen to peak around days 5-9 before rapidly resolving without treatment. Timing of viral shedding is expected to correlate closely with symptoms.

Conditions
RSV
Being tested
RSV B

What participants receive

What participants receive. In a randomised study each person is assigned to one group by chance.

  • RSV BBiological

    RSV B challenge virus

Study groups in NCT07713628
Study groupRoleWhat they receive
Group 1 - SentinelExperimentalA sentinel group of n=6 will be enrolled and will not undergo bronchoscopies
Receives: Biological: RSV B
Group 2 - BronchoscopyExperimental14 participants will be enrolled and be given the same intervention and undergo the same sampling and assessement but with additional bronchoscopy sampling at 3 timepoints
Receives: Biological: RSV B

What is being measured

The primary outcome is the main question the study is designed to answer.

  1. Number, frequency and severity of Adverse Events (AEs) and Serious Adverse Events (SAEs) Adverse Events (AEs) from the viral challenge (Day 0) up to Day 28.

    AEs may pertain to:

    • Solicited symptoms when they are reported as 'severe' or when they last longer than 14 days.
    • Unsolicited symptoms.

    Measured: 28 Days

  2. Number, frequency and severity of Adverse Events (AEs) and Serious Adverse Events (SAEs) Adverse Events (AEs) relating to the bronchoscopy sampling in those undergoing bronchoscopy procedures (Group 2)

    • Solicited symptoms when they are reported as 'severe' or when they last longer than 14 days.
    • Unsolicited symptoms.

    Measured: 28 Days

  3. Occurrence of clinically significant abnormalities and changes from baseline in clinical laboratory tests up to and including Day

    Occurrence of clinically significant abnormalities and changes from baseline in clinical laboratory tests up to and including Day 7:

    • Haematology.
    • Biochemistry.

    Measured: 7 days

  4. Occurrence of clinically significant abnormalities and changes from baseline in clinical measurements and assessments (physical examination, vital signs, ECG or Spirometry) from viral challenge (Day 0) up to Day 28.

    Occurrence of clinically significant abnormalities and changes from baseline in clinical measurements and assessments (physical examination, vital signs, ECG or Spirometry) from viral challenge (Day 0) up to Day 28.

    Measured: 28 Days

  5. Infection rate in older adult participants after inoculation with a GMP wild-type RSV B

    Infection defined by:

    • RSV RNA detectable by qPCR in nasal swab on 2 or more consecutive measurements, the first occurring between 2-8 days (inclusive) post-inoculation.
    • Infection rate equalling the number of infected participants divided by the sum of all participants inoculated with the virus, expressed as a percentage.

    Measured: 8 Days

Secondary outcomes (11)
  1. RSV B viral dynamics in upper respiratory samples

    Viral load over time, determined by virus-specific qPCR:

    • Onset of viral shedding (tlag)

    Measured: 8 Days

  2. RSV B viral dynamics in upper respiratory samples

    Viral load over time, determined by virus-specific qPCR:

    • Peak of viral titer (Vmax)

    Measured: 8 Days

  3. RSV B viral dynamics in upper respiratory samples

    Viral load over time, determined by virus-specific qPCR:

    • Time-to-peak viral load (tmax)

    Measured: 8 Days

  4. RSV B viral dynamics in upper respiratory samples

    Viral load over time, determined by virus-specific qPCR:

    • Duration of viral shedding (viral load above detection limit)

    Measured: 8 Days

  5. RSV B viral dynamics in upper respiratory samples

    Viral load over time, determined by virus-specific qPCR:

    • Area under the curve (AUC) for RSV viral load (from Day 2 until Day 8).

    Measured: 8 Days

  6. RSV disease after inoculation with a GMP wild-type RSV B strain

    Self-reported solicited symptom scores as recorded by the Modified Jackson score and WURSS-24 questionnaire to establish:

    • Total symptom score.

    Measured: 14 Days

  7. RSV disease after inoculation with a GMP wild-type RSV B strain

    Self-reported solicited symptom scores as recorded by the Modified Jackson score and WURSS-24 questionnaire to establish:

    • Peak total daily symptom score.

    Measured: 14 Days

  8. RSV disease after inoculation with a GMP wild-type RSV B strain

    Self-reported solicited symptom scores as recorded by the Modified Jackson score and WURSS-24 questionnaire to establish:

    • Area Under the Curve of total daily symptom scores

    Measured: 14 Days

  9. RSV disease after inoculation with a GMP wild-type RSV B strain

    Occurrence of RSV B disease as number and proportion of inoculated participants who develop symptomatic RSV over total number of participants inoculated.

    Measured: 8 Days

  10. Systemic antibody response to challenge RSV B infection

    Serum neutralizing antibody titre at baseline (day -1) and 28 post-inoculation.

    Measured: 28 Days

  11. Systemic antibody response to challenge RSV B infection

    Frequency of seroconversion (defined as more than or equal to 4-fold rise in neutralizing antibody titre) in blood at day 28 compared with baseline

    Measured: 28 Days

Timeline

From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.

  1. First posted20 Jul 2026
  2. Study start1 Aug 2026 (estimated)
  3. Primary completion30 May 2028 (estimated)
  4. Study completion30 May 2028 (estimated)

Resources

More details

For doctors and researchers: how the study is designed, who runs it, and its registry IDs.

Study design
Study type
Interventional
Phase
Phase N/A
Primary purpose
Basic science
Allocation
Non-randomised
Intervention model
Sequential
Model description
Group 1 (Sentinel) Group 2 (Bronchoscopy)
Masking
None (open label)
Enrolment
20 participants (estimated)
IDs, dates and publications
ClinicalTrials.gov ID
NCT07713628
Sponsor's protocol ID
204808
Acronym
CHIRP02
Status last verified
Apr 2026
First submitted
14 Jul 2026
Last updated
20 Jul 2026
Results posted
No
Data monitoring committee
Yes
FDA-regulated drug
No
FDA-regulated device
No

Questions about this trial

What is this clinical trial studying?

A study testing RSV B in people with RSV, run by Imperial College London.

The full registered description is in the About this study section and the official record.

Who may be eligible to take part?

The sponsor lists 4 inclusion and 50 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.

Is this clinical trial currently recruiting?

The record says: opening soon, as of the sponsor's last update on 20 Jul 2026. Status can change between updates, so confirm with the study contact before making plans.

What are the possible benefits and risks?

They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.

Are results available for this study?

This study is still under way. Results are not available in the source record yet.

How can a doctor refer a patient or contact the research team?

Contact Polly Fox-Sheehan, BSc, MSc (02033131282, polly.fox@imperial.ac.uk), or a site near the patient. AzTrials does not enrol participants or take referrals.

What does the primary outcome measure?

Number, frequency and severity of Adverse Events (AEs) and Serious Adverse Events (SAEs) Adverse Events (AEs) from the viral challenge (Day 0) up to Day 28. (time frame: 28 Days). The study lists 5 primary outcomes in all. It is what the study was designed to measure, not a finding.

Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?

No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.

How often is this information updated?

AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 20 Jul 2026.

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