Randomised, Double-Blind, Placebo-Controlled, Parallel Group Study to Assess the Efficacy and Safety of 4 Weeks of Treatment of Orally Inhaled BI 1744 CL (3 - 4 Doses) Delivered by the Respimat® Inhaler in Patients With COPD

Study start date: March 1, 2007

Inclusion Criteria: 1. All patients must sign an informed consent consistent with ICH-GCP guidelines prior to participation in the trial, which includes medication washout and restrictions 2. All patients must have a diagnosis of chronic obstructive pulmonary disease and must meet the following spirometric criteria: Patients must have relatively stable, moderate to severe airway obstruction with a post-bronchodilator FEV1 \&#61619; 30% of predicted normal and \< 80% of predicted normal and a post-bronchodilator FEV1 / FVC \< 70% at Visit 1 3. Male or female patients, 40 years of age or older 4. Patients must be current or ex-smokers with a smoking history of more than 10 pack years. Patients who have never smoked cigarettes must be excluded 5. Patients must be able to perform technically acceptable pulmonary function tests and PEFR measurements, and must be able to maintain records (Patient Daily e-Diary) during the study period as required in the protocol 6. Patients must be able to inhale medication in a competent manner from the Respimat® inhaler and from a metered dose inhaler (MDI). Exclusion Criteria: Selection of relevant exclusion criteria: 1. Patients with a history of asthma or a total blood eosinophil count 600/mm3. 2. Patients with any of the following conditions: * a diagnosis of thyrotoxicosis * a diagnosis of paroxysmal tachycardia (\>100 beats per minute) * a marked baseline prolongation of QT/QTc interval (e.g. repeated demonstration of a QTc interval \> 450 ms). * a history of additional risk factors for Torsade de Pointes (TdP) (e.g. heart failure, hypokalemia, family history of Long QT Syndrome) 3. Patients with any of the following conditions: * a history of myocardial infarction within 1 year of screening visit (Visit 1) * a diagnosis of clinically relevant cardiac arrhythmia * known active tuberculosis * a malignancy for which patient has undergone resection, radiation therapy or chemotherapy within last five years (patients with treated basal cell carcinoma are allowed) * a history of life-threatening pulmonary obstruction * a history of cystic fibrosis * clinically evident bronchiectasis * a history of significant alcohol or drug abuse 4. Patients who have undergone thoracotomy with pulmonary resection 5. Patients who regularly use daytime oxygen therapy for more than one hour per day and in the investigator's opinion will be unable to abstain from the use of oxygen therapy during clinic visits 6. Patients who have completed a pulmonary rehabilitation program in the six weeks prior to the Screening Visit (Visit 1) or patients who are currently in a pulmonary rehabilitation program 7. Patients who have taken an investigational drug within one month or six half lives (whichever is greater) prior to Screening Visit (Visit 1) 8. Pregnant or nursing women 9. Women of childbearing potential not using a highly effective method of birth control 10. Patients who have previously been randomized in this study or are currently participating in another study 11. Patients who are unable to comply with medication restrictions.