 - with a documented diagnosis of mild, moderate or severe chronic obstructive pulmonary disease COPD according to Global Initiative for Chronic Obstructive Lung Disease GOLD criteria and 20-pack year history of smoking, a post-bronchodilator 40 FEV1 80 of predicted normal and post-bronchodilator FEV1FVC 70 who have signed an informed consent form ICF prior to the initiation of any study-related procedure Post bronchodilator refers to 30 minutes after the inhalation of 400 μg of salbutamol 