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AsthmaNCT02703467

Exhaled Hydrogen Sulphide as a Biomarker of Airways Disease in Asthma

An observational study of Asthma, run by Imperial College London at 1 site in United Kingdom.

Completed

Finished. The study has ended and is not enrolling. Results may be posted on the official record.

Official record
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Trial summary

The purpose of this study will be to determine whether there is any role for measuring Hydrogen Sulphide (H2S) in the exhaled breath in terms of management of the patient with asthma. The investigators will recruit patients with a range of severity of asthma and health volunteers. Read more about this study

Who is it for?
Ages 18 years and olderHealthy volunteers can take part
Conditions the study is for
Asthma
How many people
70 participants
Where
1 siteUnited Kingdom
Study dates
1 Aug 2015to 30 Jun 2016
Phase
Observational
Are there results?
Yes, posted in the registrySummary in the doctors' view

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 18 years and older
  • All sexes
  • Healthy volunteers accepted
  • Adult, Older adult

Study population: The investigators will recruit a cohort healthy subjects by advertisement within the Hospital and within the general public (by newspaper advertisement). The investigators will also recruit subjects with asthma from paients attending Asthma Clinics at the Royal Brompton and Harefiled NHS Trust.

Who may be able to join

  • All patients must be able to give informed consent. The definition of the severity of their asthma will be according to the GINA (Global Initiative for Asthma) guidelines dependent on the amount of therapy needed to control asthma. The investigators will also include at least 45 patients with severe asthma defined on the basis of: Uncontrolled asthma: three or more of the following features present in any week in the previous 4 weeks:
  • Daytime symptoms more than twice per week
  • Any limitation of activities
  • Nocturnal symptoms once or more per week
  • Need for reliever treatment more than twice per week
  • Pre bronchodilator FEV1 <80% predicted or personal best OR
Show all 14Show fewer
  • Frequent severe exacerbations (≥2 per year) OR
  • Require prescription of daily or alternate day oral corticosteroids (OCS) to achieve asthma control despite the prescription of high dose inhaled corticosteroids (>1000mcg fluticasone propionate daily or equivalent) or maintenance oral corticosteroids plus a long acting beta agonist or one other controller medication (for example anti-cholinergics, leukotriene receptor antagonists or theophylline).
  • Diagnosis of asthma for the asthma cohort: Subjects must have asthma according to one or more of the following criteria documented in the last 12 months
  • improvement in FEV1 ≥ 12% and 200ml predicted after inhalation of 400 mcg salbutamol
  • airway hyper-responsiveness (PC20 <8mg/ml)
  • diurnal variation in PEF: amplitude % mean of twice daily PEF > 8%
  • decrease in pre bronchodilator FEV1 >12% and >200mls within 4 weeks after tapering treatment with one or more of the following drugs: inhaled corticosteroids, oral corticosteroids, long-acting beta-agonists, long-acting beta-agonists and short-acting beta-agonists.
  • PLUS a history of wheeze occurring spontaneously or on exertion

Who cannot join

  • Current smoker, or Ex-smoker with a >10 year pack history or having smoked within the past 6 months.
  • Significant alternative diagnoses that may mimic or complicate asthma, in particular dysfunctional breathing, panic attacks, and overt psychosocial problems (if these are thought to be the major problem rather than in addition to severe asthma)
  • Significant other primary pulmonary disorders in particular pulmonary embolism, pulmonary hypertension, interstitial lung disease and lung cancer
  • Subjects with emphysema and bronchiectasis should only be excluded if this is thought to be the major pulmonary disorder rather than in addition to severe asthma
  • Diagnosis or current investigation of occupational asthma
  • Any subjects currently participating, or having participated within 3 months of the first dose in a study using a new molecular entity, or the first dose in any other study investigating drugs.

Trial locations and contacts

1 site in 1 country.

United Kingdom1 site
  • Royal Brompton Hospital

    London, SW3 6HP

Other trials in United Kingdom

About this study

The purpose of this study will be to determine whether there is any role for measuring Hydrogen Sulphide (H2S) in the exhaled breath in terms of management of the patient with asthma.

The investigators will recruit patients with a range of severity of asthma and health volunteers. Levels of Hydrogen Sulphide will be measured in exhaled breath and blood. Also exhaled Nitric Oxide, Spirometry and asthma symptom scores will be measured at each study visit. Participants will attend either 2 or 4 separate visits.

The investigators will determine whether there is a relationship between exhaled Hydrogen Sulphide and asthma severity.

Read the detailed description

Objectives:

  1. Perform a cross-sectional study in non-asthmatic subjects and asthmatic subjects of varying severities of the levels of Hydrogen Sulphide in exhaled breath in relation to the severity and control of asthma
  2. Compare the levels of exhaled Hydrogen Sulphide with exhaled Nitric Oxide.

We will recruit 30 health volunteers and 90 patients with a range of severity of asthma.

Particpants will attend for either 2 or 4 visits. At these visits the following measurements will be taken:

  1. Exhaled Hydrogen Sulphide
  2. Serum Hydrogen Sulphide
  3. Exhaled Nitric Oxide 3. Spirometry 4. Asthma Symptom Score (ACQ)

The investigators will use a Hydrogen Sulphide UV fluorescent machine Model T101 (0-50 ppb to 0-20 ppm) (Cal-Bay Control Inc, USA) to measure directly on line exhaled breath Hydrogen Sulphide. This method has been used previously in normal people, but we will first determine whether there is an exhaled flow-dependence on the measurement of H2S levels. The investigators will use a hand-held Nitric Oxide machine (NO Breath) to measure Nitric Oxide in exhaled breath.

Subjects must have asthma according to one or more of the following criteria documented in the last 12 months:

  1. Improvement in FEV1 (forced expiratory volume at one second) ≥ 12% and 200ml predicted after inhalation of 400 mcg salbutamol
  2. Airway hyper-responsiveness (PC20 <8mg/ml)
  3. Diurnal variation in PEF (peak expiratory flow): amplitude % mean of twice daily PEF > 8%
  4. Decrease in pre-bronchodilator FEV1 >12% and >200mls within 4 weeks after tapering treatment with one or more of the following drugs: inhaled corticosteroids, oral corticosteroids, long-acting beta-agonists, long-acting beta-agonists and short-acting beta-agonists.

PLUS A history of wheeze occurring spontaneously or on exertion

Conditions
Asthma
Keywords
Exhaled hydrogen sulphide
Medical subject headings
Asthma

What participants receive

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

Study groups in NCT02703467
Study groupRoleWhat they receive
HealthyHealthy subjects will have no significant medical history and no previous history of asthma or other serious illnesses. They should be non-smokers. The investigators willl measure spirometry and ensure that the values lie within the normal predicted range.
AsthmaticsPatients diagnosed as having asthma will be recruited from Royal Brompton Hospital Asthma Clinics. These patients will have a range of severity of asthma ranging from mild-moderate to severe asthma patients. The diagnosis of asthma is ascertained as described in the inclusion criteria.

What is being measured

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

  1. Hydrogen Sulphide in Exhaled Breath

    Level of hydrogen sulphide in exhaled breath measured as parts per billion

    Measured: At baseline visit

Secondary outcomes (4)
  1. FEV1

    Forced expiratory volume in one second as percent of predicted value (%)

    Measured: At baseline visit

  2. FVC (Forced Vital Capacity)

    Forced vital capacity as per cent of predicted

    Measured: At 4 visits which occur during the study duration, up to 1 year

  3. Exhaled Nitric Oxide

    Levels of nitric oxide in exhaled breath in parts per billion

    Measured: At 4 visits which occur during the study duration, up to 1 year

  4. Blood Hydrogen Sulpide Level

    Hydrogen Sulpide level measurements from blood

    Measured: At 4 visits which occur during the study duration, up to 1 year

Timeline

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

  1. First posted9 Mar 2016 (estimated)
  2. Study start1 Aug 2015
  3. Primary completion30 Jun 2016
  4. Study completion30 Jun 2016

Resources

More details

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

Study design
Study type
Observational
Observational model
Cohort
Time perspective
Prospective
Enrolment
70 participants (actual)
IDs, dates and publications
ClinicalTrials.gov ID
NCT02703467
Sponsor's protocol ID
13/LO/1453
Status last verified
Oct 2019
First submitted
23 Feb 2016
Last updated
21 Oct 2019
Data monitoring committee
No
FDA-regulated drug
No
FDA-regulated device
No
Individual data sharing
No

Questions about this trial

What is this clinical trial studying?

An observational study of Asthma, run by Imperial College London at 1 site in United Kingdom.

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 14 inclusion and 6 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: finished, as of the sponsor's last update on 21 Oct 2019. Status can change between updates, so confirm with the study contact before making plans.

Where is the study taking place?

The record lists 1 site in United Kingdom. Whether a site is taking part right now should be confirmed with that site. See every site.

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?

Yes. Results are posted in the registry (first posted 21 Oct 2019). A summary is in the For doctors view, and the full results are on ClinicalTrials.gov.

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

The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.

What does the primary outcome measure?

Hydrogen Sulphide in Exhaled Breath (time frame: At baseline visit). 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 21 Oct 2019.

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