PURPOSE: The recently completed randomized, multicenter, double-blind, sham-controlled Asthma Intervention Research 2 (AIR2) Trial (2 BT:1 Sham) evaluated the safety and effectiveness of BT, a novel therapeutic bronchoscopic procedure for the treatment of severe persistent asthma. BT significantly reduced severe exacerbations and emergency department (ED) visits for respiratory symptoms at 1-year post-treatment. BT treated subjects are being followed out to 5 years.
METHODS: Long-term follow-up of BT group subjects in the AIR2 Trial (subjects with severe asthma defined as symptomatic despite taking high doses of ICS (>1000μg BDP equiv.) and LABA) includes quarterly phone calls and annual in-office evaluations to assess adverse events (AE) and use of healthcare resources for asthma symptoms. Durability of treatment effect is being assessed using a non-inferiority test for proportions of subjects experiencing severe exacerbations in post-treatment Years 2, 3, 4 and 5 compared to Year 1.
RESULTS: 181 subjects in the BT group completed follow-up at 12 months and 166 subjects completed the Year 2 follow-up. There was no significant difference in the event rate (events/subject/year) or the proportion of subjects experiencing severe exacerbations (23.0 v 30.9%), asthma (multiple symptoms) AE (26.5 v 28.7%), and ED visits (6.6 v 5.0%) or hospitalizations (4.2 v 3.3%) for asthma symptoms, Year 2 v. first 12 month post-treatment period (52 weeks beyond 6 weeks after last bronchoscopy) respectively.The corresponding data for the Sham group for the first 12 months post-procedure were: Proportion of subjects: 39.8% for severe exacerbations, 42.9% for asthma (multiple symptoms) AE, 15.3% for ER visits, and 4.1% for hospitalizations; Rates (events/subject/year): 0.70 for severe exacerbations, 0.73 for asthma (multiple symptoms) AE, 0.43 for ER visits, and 0.13 for hospitalizations.
CONCLUSION: 2 years post-BT treatment there is persistent benefit as demonstrated by no significant change in AE, severe exacerbations or healthcare utilization. Follow-up beyond Year 2 is ongoing.
CLINICAL IMPLICATIONS: BT provides long term asthma control in patients with severe asthma.
DISCLOSURE: Mario Castro, University grant monies NA; Grant monies (from sources other than industry) NA; Grant monies (from industry related sources) Asthmatx; Shareholder NA; Employee NA; Fiduciary position (of any organization, association, society, etc, other than ACCP NA; Consultant fee, speaker bureau, advisory committee, etc. Astra Zeneca, Asthmatx, Boehringer Ingelheim, Electrocore, Genentech, GSK, Merck, NKTT, Pfizer, Schering; Product/procedure/technique that is considered research and is NOT yet approved for any purpose. Alair Bronchial Thermoplasty System