AIR2 Extension Study to Demonstrate Longer-term (> 1 Year) Durability of Effectiveness
Condition: Asthma
Study type: Observational

Summary: 
      The objective of this study is to evaluate durability of effectiveness (beyond one year) of
      the Alair System in patients with severe persistent asthma. The study will consist of
      Alair-group subjects who are currently in the follow-up phase (out to 5 years) of the AIR2
      Trial (Protocol #04-02, clinicaltrials.gov number NCT00231114).

      Durability of the treatment effect will be evaluated by comparing the proportion of subjects
      who experience severe exacerbations during the first year after Alair treatment with the
      proportion of subjects who experience severe exacerbations during subsequent 12 month periods
      out to 5 years.

      All Alair group subjects in the AIR2 Trial are being followed out to 5 years as per the AIR2
      Trial protocol. The data that are to be used to determine durability of effectiveness as
      described in the present protocol (Protocol #10-01) are being collected under the existing
      AIR2 Trial protocol (Protocol # 04-02).

      Study Hypothesis: An empirical demonstration of the durability of the treatment effect will
      be used to show that the proportion of subjects experiencing severe exacerbations for the
      first year compared with the proportions of subjects experiencing severe exacerbations in
      subsequent years do not get substantially worse.

      The primary statistical objective is to demonstrate that the proportion of subjects who
      experience severe exacerbations in the subsequent 12-month follow-up (for Year 2, Year 3,
      Year 4 and Year 5 [in 12-month periods]) is not statistically worse when compared with the
      proportion of first 12-months, which begins 6-weeks after the last Alair treatment. This
      objective will be met if the upper 95% confidence limit of the difference in proportions
      (i.e., the subsequent 12-month proportion minus the first 12-month proportion) is less than
      20%.
    

Detailed description: 
      This will be an open-label, single arm study designed to demonstrate the durability of
      effectiveness (beyond one year) of the Alair System in patients with severe persistent
      asthma.

      Durability of treatment effect will be evaluated by comparison of the proportion of subjects
      experiencing severe exacerbations during the first year after the Alair treatment to
      subsequent 12-month periods out to 5 years.

      The 12-month periods will begin 6 weeks post-last Alair bronchoscopy.
    

Intervention name(s): Bronchial Thermoplasty with the Alair System
Intervention type(s): Device
Intervention description(s): Bronchial Thermoplasty with the Alair System
Observational model: Cohort
Time perspective: Prospective
Sampling method: Non-Probability Sample
Study population: 
        All Alair group subjects who have participated in the AIR2 Trial (NCT00231114) and were not
        lost to follow-up at the end of the 12 month premarket visit, and those who are willing to
        comply with the study protocol and routine visits for the duration of the study will be
        included in the post-approval study.