Research in Severe Asthma (RISA) Trial

Multicenter, randomized, clinical trial conducted at 8 Investigational Sites in 3 countries. Subjects in the Alair group to be administered the Alair treatment in 3 separate bronchoscopy sessions, while subjects in the Control group will complete 3 "Control Visits" to the Physicians office, timed to coincide with the 3 treatment bronchoscopy sessions. Following completion of all three procedures or Control Visits subjects will be evaluated at 6 weeks and 12 weeks. All subjects to remain on their maintenance asthma medications until they are evaluated again at 22 weeks after the last procedure or Control Visit. This phase from the last procedure or Control Visit out to 22 Weeks after the last procedure or Control Visit is termed the Steroid Stable Phase. Subjects will undergo a 14 week period from 22 Weeks to 36 Weeks (termed the Steroid Wean Phase) during which an attempt will be made to wean them off either their maintenance inhaled corticosteroids (ICS) or, if taking maintenance oral corticosteroids (OCS), their oral steroids. If a subject cannot tolerate the steroid reduction at a particular level (as evidenced by loss of asthma control), they will be stabilized on their last tolerable dose of steroid. All subjects will maintain their reduced steroid dosage from the end of the Steroid Wean Phase at 36 weeks to their final evaluations at the end of the Study at 52 weeks (termed the Reduced Steroid Phase). All subjects will be exited from the study following completion of the 52 week evaluations.