A Phase II Randomised, Double-blind, Placebo Controlled, Cross-over Efficacy and Safety Comparison of Three Doses of Tiotropium Inhalation Solution Delivered Via Respimat Inhaler (1.25, 2.5 and 5.0 Mcg Once Daily) Versus Placebo in Patients With Moderate Persistent Asthma.

Rationale for the current trial is to evaluate the efficacy and safety of three doses (1.25 µg, 2.5 µg and 5.0 µg ex mouthpiece) of tiotropium inhalation solution in patients with moderate persistent asthma who are still symptomatic despite regular maintenance therapy with inhaled corticosteroids (ICS). The data collected in the present trial will provide useful information to health care providers and patients regarding the efficacy and safety of a once daily inhalation of three different doses of tiotropium solution delivered by the Respimat® inhaler in addition to inhaled corticosteroids in the treatment of not fully controlled moderate asthma in comparison to placebo. The Pharmacokinetics (PK) of tiotropium is well established in COPD patients. However, there is currently no PK data available for the 3 doses of tiotropium being tested in this trial in patients with moderate persistent asthma. Tiotropium is a once daily drug. Hence, the rationale for blood and urine sampling for PK analysis over 24 hours in a subset of patients is to confirm the PK of the 3 doses in moderate asthma patients. Rationale for the 24-hour pulmonary function test sub-investigation is to demonstrate that a once daily dosing of tiotropium inhalation solution is effective and safe in the treatment of moderate persistent asthma.