Unraveling Targets of Therapy in Bronchial Thermoplasty in Severe Asthma (TASMA) Extension Study

Study Overview
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Brief Summary
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This study evaluates the longterm clinical outcomes, including safety and efficacy parameters after Bronchial Thermoplasty (BT) treatment over a period of 5 years. All patients included in de TASMA trial in the Netherlands will be asked to participate in the TASMA extension study.

Official Title
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TASMA Extension Study: Long Term Efficacy and Safety of Bronchial Thermoplasty in Severe

Conditions
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Severe Asthma

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Subject participation in the TASMA study Ability and willingness to provide informed consent. Ability to comply with the study protocol Exclusion Criteria: Subject participating in another clinical trial involving respiratory intervention which in the opinion of the investigator might interfere with the study.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 65 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Severe exacerbations rate | exacerbations / subject / year measured yearly over 5 years will be compared to the health care utilization pre- and 6 months post BT-treatment. | measured yearly over 5 years | 
| Emergency room visit for respiratory symptoms rate | emergency room visits for respiratory symptoms/subject/year measured yearly over 5 years will be compared to the health care utilization pre- and 6 months post BT-treatment. | measured yearly over 5 years | 
| Hospitalization for respiratory symptoms rate | hospitalizations for respiratory symptoms/subject/year measured yearly over 5 years will be compared to the health care utilization pre- and 6 months post BT-treatment. | measured yearly over 5 years | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Pre-and post bronchodilator forced expiratory volume at one second (FEV1) and related FEV1 % reversibility | measured yearly over 5 years compared to the parameters measured pre- and 6 months post-BT treatment | measured yearly over 5 years | 
| provocative concentration causing a 20% fall (PC20 ) methacholine test | measured yearly over 5 years compared to the parameters measured pre- and 6 months post-BT treatment | measured yearly over 5 years | 
| Fractional exhaled nitric oxide (FeNO) | measured yearly over 5 years compared to the parameters measured pre- and 6 months post-BT treatment | measured yearly over 5 years | 
| Airway-resistance (sRaw) mechanics | measured yearly over 5 years compared to the parameters measured pre- and 6 months post-BT treatment | measured yearly over 5 years | 
| Airway-conductance(sGaw) mechanics | measured yearly over 5 years compared to the parameters measured pre- and 6 months post-BT treatment | measured yearly over 5 years | 
| forced oscillation technique (FOT) | measured yearly over 5 years compared to the parameters measured pre- and 6 months post-BT treatment | measured over 5 years | 
| Asthma Control Questionnaire (ACQ) scores | measured yearly over 5 years compared to the parameters measured pre- and 6 months post-BT treatment | measured yearly over 5 years | 
| Asthma Quality of Life Questionnaire (AQLQ) scores | measured yearly over 5 years compared to the parameters measured pre- and 6 months post-BT treatment | measured yearly over 5 years | 
| Maintenance dose of oral steroids | measured yearly over 5 years compared to the parameters measured pre- and 6 months post-BT treatment | measured yearly over 5 years | 
| Maintenance dose of inhaled steroids | measured yearly over 5 years compared to the parameters measured pre- and 6 months post-BT treatment | measured yearly over 5 years | 
| Rescue medication use | measured yearly over 5 years compared to the parameters measured pre- and 6 months post-BT treatment | measured yearly over 5 years | 
| Airway smooth muscle (ASM) mass | ASM mass as determined by percentage/absolute ASM surface area and distance of reticular basement membrane (RBM) to ASM layer in endobronchial biopsies | 2 years after inclusion, 2,5 years after BT | 
| optical coherence tomography (OCT) determined changes | OCT determined changes in structural airway remodelling as measured by changes in lumen area (Ai) and airway wall thickness (Aaw). | 2 years after inclusion, 2,5 years after BT | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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bronchial thermoplasty, long term, interventional bronchoscopy