Bronchial thermoplasty (BT) with the Alair System is safe for patients with moderate to severe asthma, a new study has found.

According to the five-year Asthma Intervention Research (AIR) trial, no clinical complications occurred over a five-year period post-BT in patients with moderate to severe asthma.

BT, the first device-based asthma treatment approved by the US Food and Drug Administration (FDA), is a new outpatient procedure that delivers controlled thermal energy to reduce excess airway smooth muscle, which is associated with airway constriction in patients with asthma.

The Alair BT system is for patients aged 18 years and older, whose asthma is not well controlled with inhaled corticosteroids and long-acting beta agonists.

The report showed that immediately after BT, there was an expected temporary increase in the frequency and worsening of respiratory-related symptoms but these were resolved on average within seven days of standard care.

The AIR trial data was published in the New England Journal of Medicine (NEJM) in March 2007.