Effectiveness and Safety of Bronchial Thermoplasty in the Treatment of Severe Asthma: A Multicenter, Randomized, Double-Blind, Sham-Controlled Clinical Trial.

Author(s): Castro M, Rubin AS, Laviolette M, Fiterman J, De Andrade Lima M, Shah PL, Fiss E, Olivenstein R, Thomson NC, Niven RM, Pavord ID, Simoff M, Duhamel DR, McEvoy C, Barbers R, Ten Hacken NH, Wechsler ME, Holmes M, Phillips MJ, Erzurum S, Lunn W, Israel E, Jarjour N, Kraft M, Berry SM, Quiring J, Shargill NS, Cox G

Affiliation(s): Division of Pulmonary and Critical Care Medicine, Washington University School of Medicine, St Louis, Missouri, United States.

Publication date & source: 2009-10-08, Am J Respir Crit Care Med., [Epub ahead of print]

Publication type:

BACKGROUND: Bronchial thermoplasty (BT) is a bronchoscopic procedure in which controlled thermal energy is applied to the airway wall to decrease smooth muscle. OBJECTIVE: Evaluate the effectiveness and safety of BT versus sham procedure in subjects with severe asthma who remain symptomatic despite treatment with high-dose inhaled corticosteroids and long-acting beta2-agonists. METHODS: 288 adult subjects (Intent-to-Treat (ITT)) randomized to BT or sham control underwent three bronchoscopy procedures. Primary outcome was the difference in Asthma Quality of Life Questionnaire (AQLQ) scores from baseline to average of 6-, 9-, and 12-months (integrated AQLQ). Adverse events and healthcare utilization were collected to assess safety. Statistical design and analysis of the primary endpoint was Bayesian. Target posterior probability of superiority (ppsuperiority) of BT over sham was 95%, except for the primary endpoint (96.4%). RESULTS: The improvement from baseline in the integrated AQLQ score was superior in the BT group compared to sham (BT: 1.35+/-1.10; sham: 1.16+/-1.23 (ppsuperiority 96.0% (ITT) and 97.9% (per protocol)). 79% of BT and 64% of sham subjects achieved changes in AQLQ of >/=0.5 (ppsuperiority 99.6%). 6% more BT subjects were hospitalized in the treatment period (up to 6 weeks after BT). In the post-treatment period (6a52 weeks after BT), the BT group experienced fewer severe exacerbations, emergency department (ED) visits and days missed from work/school compared to sham (ppsuperiority: 95.5%, 99.9%, and 99.3%, respectively). CONCLUSIONS: BT in subjects with severe asthma improves asthma-specific quality of life with a reduction in severe exacerbations and healthcare utilization in the post-treatment period.