Washington University Severe Asthma Research Program III (WU SARPIII)

Severe Asthma Research Program (SARP)-Washington University

The overall goal of this proposal is to better understand the basis of airway remodeling in severe asthma and how remodeling changes over time. The investigators propose to study a well-characterized cohort of adult and pediatric subjects with severe asthma using a multidisciplinary state-of-the-art approach.

Study Overview

• Status: Unknown
• Conditions: Asthma

Detailed Description

The overall goal of this proposal is to better understand the molecular basis and structural and physiologic consequences of airway remodeling in severe asthma and how remodeling changes over time. In that context, the investigators propose to study a well-characterized cohort of adult and pediatric subjects with severe asthma using a multidisciplinary approach that includes state-of-the-art morphometric, imaging, and physiologic measurements of airways. The investigators will contrast these findings to those in groups with well-controlled asthma, normal controls, and diseased controls (chronic bronchitis) to identify features that can provide biologic targets unique to severe asthma. The investigators have demonstrated that epithelial hyperplasia, goblet cell metaplasia and mucin production are features of airway remodeling in subjects with severe asthma, and that epithelial remodeling was due to increased epithelial proliferation and decreased cell death. The investigators propose that individuals with severe asthma, in comparison to well controlled asthma, have: (I) increased airway remodeling as evidenced by goblet cell metaplasia and mucin production, (II) greater airway thickness by multidetector-row CT of the chest (MDCT) leading to ventilation defects demonstrated by hyperpolarized helium (3He) MRI and air trapping demonstrated by MDCT, and (III) airway remodeling associated with more severe and progressive airflow obstruction. The investigators hypothesize that the goblet cell metaplasia and increased mucin The investigators have observed in severe asthma are being driven by an IL-13- and EGFR-dependent mechanism that inhibits epithelial cell apoptosis and allows IL-13 differentiation of the airway epithelium into goblet cells (Aim I). The investigators further hypothesize that this remodeling of segmental airways in severe asthma leads to distal ventilation defects and air trapping (Aim II). In an effort to define potential predictors of subsequent decline in lung function in severe asthma, the investigators hypothesize that baseline airway remodeling as reflected by MDCT airway wall area (AWA%) is predictive of FEV1 (post-corticosteroid/bronchodilator FEV1) decline (Aim III). The identification of potential variables associated with remodeling and severe asthma will help identify individuals at risk whom would benefit from specific targeted therapy. The concerted efforts of this project together with the SARP will lead to new insights on the mechanistic basis for severe asthma, further elucidate how it differs from mild-moderate asthma, identify potential targets for intervention, and will provide imaging metrics to objectively evaluate outcomes for new treatments.

• Study Type: Observational
• Enrollment (Actual): 121

Contacts and Locations

Study Locations

• United States
  • Missouri
    • Saint Louis, Missouri, United States, 63110
      • Washington University School of Medicine

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 6 years and older (Child, Adult, Older Adult)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: All

• Sampling Method: Non-Probability Sample

Study Population

Subjects with asthma (severe asthma, well controlled asthma) and healthy normal controls from St. Louis region

Description

Inclusion Criteria:

1. Physician diagnosis of asthma,
2. Age 6 years and older

3. Evidence of historical reversibility, including either:

   1. FEV1 bronchodilator reversibility ≥ 12%, or
   2. Airway hyperresponsiveness reflected by a methacholine PC20 ≤16 mg/mL.

Exclusion Criteria:

1. No primary medical caregiver,
2. Pregnancy (if undergoing methacholine challenge or bronchoscopy),
3. Current smoking
4. Smoking history > 10 pack years if ≥ 30 years of age or smoking history > 5 pack years if < 30 years of age (Note: If a subject has a smoking history, no smoking within the past year)
5. Other chronic pulmonary disorders associated with asthma-like symptoms,including (but not limited to) cystic fibrosis, chronic obstructive pulmonary disease, chronic bronchitis, vocal cord dysfunction that is the sole cause of asthma symptoms, severe scoliosis or chest wall deformities that affect lung function, or congenital disorders of the lungs or airways,
6. History of premature birth before 35 weeks gestation,
7. Evidence that the participant or family may be unreliable or poorly adherent to their asthma treatment or study procedures,
8. Planning to relocate from the clinical center area before study completion, or
9. Any other criteria that place the subject at unnecessary risk according to the judgment of the Principal Investigator and/or attending physician(s) of record.

Study Plan

How is the study designed?

Number of groups / cohorts

3

Cohorts and Interventions

Group / Cohort
Well controlled asthma; Subjects with well controlled asthma
Normal control; Subjects that are healthy normals
Severe Asthma; Subjects with severe asthma (SARP protocol definition)

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Lung function	decline in lung function (FEV1) over 3 yrs	3 yrs

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Asthma Control Questionnaire	asthma control score (ACQ)	3 yrs
Health care utilization	Health care utilization including ED visits and hospitalizations.	3 yrs
Exacerbation	Exacerbations requiring systemic steroids	3 yrs
CT quantification	CT airway wall thickness, lung density	3 yrs
MRI	Ventilation defects on hyperpolarized gas MRI	3 yrs
Morphometric biopsy	Morphometric analysis of airway biopsies	3 yrs
Gene expression	Gene expression studies of airway epithelial cells	3 yrs

Collaborators and Investigators

• Sponsor: Washington University School of Medicine
• Investigators: Principal Investigator: Kaharu Sumino, MD, Washington University School of Medicine

Publications and helpful links

General Publications

• Dunican EM, Elicker BM, Gierada DS, Nagle SK, Schiebler ML, Newell JD, Raymond WW, Lachowicz-Scroggins ME, Di Maio S, Hoffman EA, Castro M, Fain SB, Jarjour NN, Israel E, Levy BD, Erzurum SC, Wenzel SE, Meyers DA, Bleecker ER, Phillips BR, Mauger DT, Gordon ED, Woodruff PG, Peters MC, Fahy JV; National Heart Lung and Blood Institute (NHLBI) Severe Asthma Research Program (SARP). Mucus plugs in patients with asthma linked to eosinophilia and airflow obstruction. J Clin Invest. 2018 Mar 1;128(3):997-1009. doi: 10.1172/JCI95693. Epub 2018 Feb 5.
• Witt CA, Sheshadri A, Carlstrom L, Tarsi J, Kozlowski J, Wilson B, Gierada DS, Hoffman E, Fain SB, Cook-Granroth J, Sajol G, Sierra O, Giri T, O'Neill M, Zheng J, Schechtman KB, Bacharier LB, Jarjour N, Busse W, Castro M; NHLBI Severe Asthma Research Program (SARP). Longitudinal changes in airway remodeling and air trapping in severe asthma. Acad Radiol. 2014 Aug;21(8):986-93. doi: 10.1016/j.acra.2014.05.001.

Helpful Links

• SARP website

Study record dates

Study Major Dates

• Study Start (Actual): October 1, 2012
• Primary Completion (Anticipated): March 1, 2021
• Study Completion (Anticipated): March 1, 2021

Study Registration Dates

• First Submitted: October 25, 2012
• First Submitted That Met QC Criteria: October 26, 2012
• First Posted (Estimate): October 29, 2012

Study Record Updates

• Last Update Posted (Actual): October 6, 2020
• Last Update Submitted That Met QC Criteria: October 5, 2020
• Last Verified: October 1, 2020

More Information

Terms related to this study

• Keywords: asthma
• Additional Relevant MeSH Terms: Respiratory Tract Diseases; Immune System Diseases; Lung Diseases; Hypersensitivity, Immediate; Bronchial Diseases; Lung Diseases, Obstructive; Respiratory Hypersensitivity; Hypersensitivity; Asthma
• Other Study ID Numbers: 201206102