A Phase III Randomised, Double-blind, Placebo-controlled, Parallel-group Trial to Evaluate Efficacy and Safety of Tiotropium Inhalation Solution Delivered Via Respimat® Inhaler (5 mcg/Day) Over 48 Weeks as add-on Controller Therapy on Top of Usual Care in Patients With Severe Persistent Asthma

The trial is a randomised, double-blind, placebo-controlled, parallel-group trial to evaluate the efficacy and safety of 5 µg tiotropium over a 48-week treatment period as compared to placebo. Tiotropium inhalation solution delivered by the Respimat® inhaler will be examined as add-on controller therapy on top of usual care in patients with severe persistent asthma. The primary objective of each trial is to evaluate the long term efficacy of tiotropium over placebo on top of usual care in patients with severe persistent asthma as determined by pulmonary function testing, effects on asthma exacerbations, effects on quality of life, on asthma control and health care resource utilisation. The secondary objective of each trial is to compare the long term safety of tiotropium with placebo in this patient population.