Clinical trial NCT04514913: Study of Focal Airway Disease in Asthma Using Image Guided Bronchoscopy
Official title: Study of Focal Airway Disease in Asthma Using Image Guided Bronchoscopy
Study type: OBSERVATIONAL
Overall status: WITHDRAWN
Conditions: Asthma
Mucus; Plug, Tracheobronchial
Keywords: Asthma
Mucus Plug
Bronchoscopy
CT Scan
Lead sponsor: University of California, San Francisco
Sponsor class: OTHER
Collaborators: name: National Institutes of Health (NIH)
name: National Heart, Lung, and Blood Institute (NHLBI)
First posted: 2020-08-17
Enrollment: 0
Sex: ALL
Minimum age (years): 18
Maximum age (years): 70
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Observational model: COHORT
Time perspective: CROSS_SECTIONAL
Sampling method: NON_PROBABILITY_SAMPLE
Study population: Participants with asthma who present with or without mucus plugs, as well as healthy controls, all between the ages of 18 and 70.

Brief summary: This is a single center study of 60 subjects including those with asthma and mucus plugging, those with asthma and without mucus plugging, and healthy controls. Screening data will be reviewed to determine participant eligibility. Participants who meet all inclusion criteria will participate in image-guided bronchoscopy ("virtual navigation bronchoscopy" \[VNB\]) to sample airway biospecimens in mucus plugged and control airways.

Detailed description: This is a single center study of 60 subjects. The investigators will enroll 30 subjects with asthma who demonstrate mucus plugging on a screening CT lung scan, 15 subjects with asthma without mucus plugging, and 15 healthy controls. The healthy controls and subjects with asthma but without mucus plugging with also undergo CT scans to confirm that their lungs aren't obstructed by mucus.

Screening data will be reviewed to determine participant eligibility. Participants who meet all inclusion criteria will participate in image-guided bronchoscopy ("virtual navigation bronchoscopy" \[VNB\]) to sample airway biospecimens in mucus plugged and control airways. Subjects will participate in up to 5 study visits at the Airway Clinical Research Center.

Eligibility criteria: Group 1: Healthy Controls

Inclusion Criteria:

* Male or female between the ages of 18 and 70 years at Visit 1 and at least 50% whose age is \> 40 years (to ensure age balance among groups and anticipating that group 3 subjects will be older).
* Written informed consent obtained from subject and ability for subject to comply with the requirements of the study.
* Able to perform reproducible spirometry according to ATS criteria.

Exclusion Criteria:

* Upper respiratory tract infection (URI) within the previous 6 weeks.
* History of lung disease.
* Smoking of tobacco or other recreational inhalants in last month and/or \>10 pack-year smoking history.
* Currently pregnant.
* History of allergic rhinitis.
* Laboratory evidence of atopy (blood eosinophils \> 0.4 cells/dL, IgE \> 165 IU/mL)
* History of unstable cardiovascular disease.
* BMI \> 45
* Currently taking anticoagulants.

Group 2: Asthmatic Subjects without Mucus Plugs

Inclusion Criteria:

* Male or female between the ages of 18 and 70 years at Visit 1 and at least 50% whose age is \> 40 years (to ensure age balance among groups and anticipating that group 3 subjects will be older).
* Written informed consent obtained from subject and ability for subject to comply with the requirements of the study.
* Able to perform reproducible spirometry according to ATS criteria.
* Physiological evidence of airflow obstruction (FEV1 bronchodilator reversibility of ≥ 12% or hyperreactivity to methacholine reflected by a methacholine PC20 ≤ 16 mg/mL). Historical methacholine data from previous studies conducted in the past 5 years at the UCSF ACRC will be allowed.
* Clinical history of asthma per patient report or medical record.
* Asthma requiring treatment with inhaled corticosteroids (ICS) for 3 months or greater.

Exclusion Criteria:

* Asthma exacerbation or URI within the previous 6 weeks.
* Currently pregnant.
* Smoking of tobacco or other recreational inhalants in last month and/or \>10 pack-year smoking history.
* Other chronic pulmonary disorders, including cystic fibrosis and chronic obstructive pulmonary disease.
* History of unstable cardiovascular disease.
* BMI \> 45.
* Currently taking anticoagulants.

Group 3: Asthmatic Subjects with Mucus Plugs

Inclusion:

* Male or female between the ages of 18 and 70 years at Visit 1.
* Written informed consent obtained from subject and ability for subject to comply with the requirements of the study.
* Able to perform reproducible spirometry according to ATS criteria.
* Physiological evidence of airflow obstruction (FEV1 bronchodilator reversibility of ≥ 12% or hyperreactivity to methacholine reflected by a methacholine PC20 ≤ 16 mg/mL). Historical methacholine data from previous studies conducted in the past 5 years at the UCSF ACRC will be allowed.
* Clinical history of asthma per patient report or medical record.
* Asthma requiring treatment with inhaled corticosteroids (ICS) for 3 months or greater.
* A MDCT lung scan indicating a mucus plug accessible by bronchoscopy in at least one airway.

Exclusion Criteria:

* Asthma exacerbation or URI within the previous 6 weeks.
* Currently pregnant.
* Smoking of tobacco or other recreational inhalants in last month and/or \>10 pack-year smoking history.
* Other chronic pulmonary disorders, including cystic fibrosis and chronic obstructive pulmonary disease.
* History of unstable cardiovascular disease.
* BMI \> 45.
* Currently taking anticoagulants.
* Mucus plugs inaccessible by bronchoscope.

Primary outcomes:
measure: Difference in eosinophil percentage in broncheoalveolar biospecimens between asthmatic and non-asthmatic airways
timeFrame: 6 months
measure: Difference in gene expression of genes that mark IL-13 activation between asthmatic and non-asthmatic airways
timeFrame: 6 months
Secondary outcomes:
Other outcomes:
Locations:
city: San Francisco
country: United States
facility: UCSF Airway Clinical Research Center
state: California
Study officials:
affiliation: University of California, San Francisco
name: John Fahy, MD, MSc
role: PRINCIPAL_INVESTIGATOR
References: