Established long-term effectiveness and safety:
5 years of clinical trial follow-up data
12+ years of clinical experience
Asthma Intervention Research 2 (AIR2) Trial: At 1 year, patients with severe asthma showed significant improvement in their asthma-related quality of life after treatment with Bronchial Thermoplasty (BT) delivered by the Alair™ System:
- Quality of life improvement: 79% of patients who were treated with BT reported a significant improvement in their asthma-related quality of life1
- Fewer absences: 66% fewer asthma-related days lost from work, school, and other activities, compared with sham-controlled patients1
AIR2 Trial 5-Year Extension Study: This study evaluated the sustained effectiveness of BT beyond 1 year, and the safety of BT out to 5 years in the BT-treated patients from the AIR2 Trial.2
Fewer exacerbations, with effectiveness maintained out to 5 years
- 32% decrease in severe asthma exacerbations (requiring systemic corticosteroids) at 1 year, compared with sham-controlled patients1
- Reduction in exacerbations seen at 1 year maintained out to 5 years2
44% average decrease over 5 years in the percentage of patients having severe exacerbations, compared with 1 year prior to BT treatment2
5-year reduction in severe exacerbations requiring systemic corticosteroids
- The decrease in severe exacerbations over 5 years included a substantial reduction in the use of systemic corticosteroids associated with those exacerbations2
- Fewer asthma exacerbations means reduced need for the associated oral steroid treatment and its side effects
Fewer emergency room visits, with reduction maintained out to 5 years
- 84% reduction in emergency room visits for respiratory symptoms at 1 year, compared to sham-controlled patients1
- Reduction in ER visits seen at 1 year maintained out to 5 years2
78% average decrease over 5 years in the percentage of patients experiencing ER visits for respiratory symptoms, compared with 1 year prior to BT treatment2
Safety maintained over 5 years
- No increase was seen in hospitalizations, asthma symptoms, or respiratory adverse events over the course of 5 years2
- No structural changes due to BT in the airways (based on HRCT review) at 5 years that were clinically significant2
- No clinically significant deterioration in lung function (FEV1) at 5 years2
As with any procedure, there are risks, and individual results may vary. The most common adverse event of BT is a temporary worsening of respiratory-related symptoms. These events typically occur within one day of the BT procedure and usually resolve within a week with standard care. There is a small risk (3.4% per procedure) that symptoms may require hospitalization.
Clinical studies for BT
BT has been studied in a rigorous, stepwise fashion beginning with animal studies, followed by 4 clinical studies in asthma patients, 3 of which were randomized, controlled clinical trials, and all with 5 years of follow-up. Two clinical studies focused on the severe asthma patient population.
The Asthma Intervention Research 2 (AIR2) Trial is one of the largest sham-controlled medical device trials in pulmonary medicine. At 1 year, patients with severe asthma treated with BT showed significant improvement compared to sham-controlled patients.1,2
‡ Asthma Intervention Research (AIR)
§ Research in Severe Asthma (RISA)
Selected studies are shown below. Click on the individual trial name below for additional information on each clinical study.
1. Castro M, et al, for the AIR2 Trial Study Group. Am J Respir Crit Care Med. 2010;181:116-124.
2. Wechsler M, et al; for the AIR2 Trial Study Group [published ahead of print September, 2013].
J Allergy Clin Immunol. doi:10.1016/j.jaci.2013.08.009.
3. Cox G, et al. Am J Respir Crit Care Med. 2006;173:965-969.
4. Cox G, et al. N Engl J Med. 2007;356:1327-1337.
5. Thomson N, et al, for the AIR Trial Study Group. BMC Pulm Med. 2011;1-9.
6. Pavord I, et al, and the RISA Trial Study Group. Am J Respir Care Med. 2007;176:1185-1191.
7. Castro M, et al, for the AIR2 Trial Study Group. Ann Allergy Asthma Immunol. 2011;107:65-70.