Bronchial thermoplasty is a new bronchoscopic procedure that delivers controlled thermal energy to the bronchial wall of conducting airways, with the intent to inhibit airway smooth muscle contractile function. This offers the potential to attenuate bronchoconstriction occurring during asthma exacerbations.
We studied bronchial thermoplasty with the Broncus™ Alair™ System in subjects with a range of asthma severity, from mild to moderately-severe. Baseline and post-treatment evaluations included spirometry, methacholine chloride (MCh) challenge, CT scan and daily diary recording of peak flow, symptoms and medication usage. Treatments of all accessible upper and lower lobe airways, of 3 - 10 mm diameter, were staged in up to four sessions, a minimum of three weeks apart.
Sixteen subjects with chronic stable asthma (no change in asthma medication or unscheduled visit to healthcare provider over ≥ 6 weeks) were enrolled and treated, without serious adverse effect. There was no evidence of airway narrowing in treated airways when examined at subsequent treatment sessions. Side effects were common but were transient and self-limited, the most frequent were cough (23%) and wheeze (12%). Subjects demonstrated improvement in MCh PC20, with a mean increase of 2.5 doubling doses.CONCLUSIONS: This early experience suggests that bronchial thermoplasty is well-tolerated in the short term in selected subjects with asthma.
The potential for bronchial thermoplasty to be effective treatment of asthma is now being studied in the randomized, multi-center AIR Trial.
G. Cox, Broncus Technologies Inc., Industry, Discussion of product research or unlabeled uses of Product.