A study to investigate the underlying molecular characteristics of allergic asthma
- Conditions
- Mild to moderate asthmaSevere allergic asthmaRespiratory - AsthmaInflammatory and Immune System - Allergies
- Registration Number
- ACTRN12614001109695
- Lead Sponsor
- John Hunter Hospital
- Brief Summary
Not available
- Detailed Description
Not available
Recruitment & Eligibility
- Status
- Recruiting
- Sex
- All
- Target Recruitment
- 50
Participants:
This is a prospective case control study; we will recruit the following subjects:
1.Stable allergic asthma. Subjects aged 6 – 75 years with mild-to-moderate asthma (control of asthma symptoms (Asthma control questionnaire (ACQ6) score <1.5), and who have evidence of AHR to hypertonic saline and allergic sensitization to common inhalant allergens. On less than 1000mcg/d beclomethasone equivalent.
2.Severe uncontrolled allergic asthma, suitable for Omalizumab. Participants with severe refractory asthma, 18 years and older who have persistent poor asthma control (ACQ6 >1.5) despite treatment with greater than 1000mcg/d beclomethasone equivalent per day and a history of an acute exacerbation in the last 12 months requiring systemic corticosteroids for 3 days or more, and who are suitable for commencement of treatment with omalizumab.
3.Healthy controls. Non-asthmatic subjects aged 6 – 75 years with normal lung function and no allergic sensitization.
Key inclusion criteria
Cases with severe allergic asthma
*Asthma diagnosis, and who have evidence of AHR to hypertonic saline or change in FEV1 following bronchodilator >12% and at least 200mls.
*Age: 18 years and older and determined to be suitable for omalizumab treatment
*Regular maintenance treatment with inhaled corticosteroid and long acting beta agonist (dose of ICS >1000mcg/d fluticasone or 1600mcg/d of budesonide)
*Evidence of atopy, defined by positive skin prick test or RAST.
*Total serum IgE >75 IU/ml
*Persistent poor symptom control (ACQ6 >1.5).
*Oral corticosteroid use of at least 10mg/d of prednisone for at least 6 weeks in the last 12 months.
*Current non-smoker with <10 pack year history of smoking
Cases with controlled mild to moderate allergic asthma
*Asthma diagnosis, and who have evidence of AHR to hypertonic saline or change in FEV1 following bronchodilator >12% and at least 200mls.
*Age 6 -75 years
*Regular maintenance treatment with inhaled corticosteroid (dose of ICS <1000mcg/d fluticasone or 1600mcg/d of budesonide)
*Evidence of atopy, defined by positive skin prick test or RAST.
*Good asthma symptom control (ACQ6 <1.5)
*Current non-smoker with <10 pack year history of smoking
Healthy controls
*Normal lung function; FEV1 >80% predicted, FER >70% predicted and no evidence of AHR to hypertonic saline or change in FEV1 following bronchodilator >12% and at least 200mls.
*Age 6 -75 years
*No previous history of chronic cardiac or respiratory disease
*Non-atopic, negative skin prick test or RAST
*Current non-smoker with <10 pack year history of smoking
*Acute exacerbation of asthma within the last 4 weeks that required a change in treatment
*History of a viral respiratory tract infection within the last 4 weeks.
*Current smoker or former smoker with >10 pack year history of smoking.
*Inability to understand or comply with the study requirements
Study & Design
- Study Type
- Interventional
- Study Design
- Not specified
- Primary Outcome Measures
Name Time Method To determine if individuals with poorly controlled allergic asthma who have persistent eosinophilic airway inflammation, also have impaired antiviral responses to RV. Characterised by impaired TLR7 signaling and increased CCL7 at baseline. These analyses will be determined using ELISA and FACscan.[Loss of asthma control (within the ICS withdrawal period (i.e. 8 weeks) for mild asthmatics; or within 6 months for the severe athma group; or, in healthy controls, the contraction of a cold during the 6 months following baseline assessment.]
- Secondary Outcome Measures
Name Time Method il[Nil]