Comparison of 24 Hour Bronchodilator Efficacy of Tiotropium 18 mcg Delivered Via DISCAIR Versus SPIRIVA 18 µg Delivered Via HANDIHALER® in Patients With Moderate to Severe COPD

Inclusion Criteria: * Patients aged 40 years and older with moderate to severe COPD diagnosis * Current/former smokers with at least a 10 pack-year history of cigarette smoking * Patients with established clinical COPD and severity defined as a post-broncodilator FEV1/FVC ratio of ≤0.70 and FEV1 ≤80 % of predicted normal at screening * Females of non-child bearing potential or females of child bearing potential with negative pregnancy test; and acceptable contraceptive methods * Have no excacerbation within last 4 weeks * Hava capability of communicate with investigator * Accept to adapt the procedures of study protocol * Signed and dated informed consent Exclusion Criteria: * History of hypersensitivity to anticholinergics * Diagnosis of asthma * History of alergic rinit and athopy * Current or history of lung cancer * Known symptomatic prostatic hypertrophy requiring drug therapy * Known narrow-angle glaucoma requiring drug therapy * Have experienced exacerbation of COPD or lower respiratory inflammatory disease requiring use of antibiotics, oral or parenteral corticosteroids (CS) within 4 weeks prior to screening visit and/or during run-in period * Patients vaccinated with poored virüs vaccinate within 2 weeks prior to screening visit and/or during run-in period * Patients with a recent history of myocardial infarction, acute ischemic cardiac disease or severe cardiac arrhythmia requiring drug therapy * Women who are pregnant or lactating or are planning on becoming pregnant during the study