To Evaluate Effectiveness of Aclidinium Bromide/Formoterol Fumarate Dihydrate in Chronic Obstructive Pulmonary Disease

Inclusion Criteria: Patient is aged 40 years or older; * Confirmed diagnosis of COPD; * Spirometry performed at study entry or within the last 3 months preceding study entry with a post-bronchodilator Forced Expiratory Volume in 1 Second/Forced Vital Capacity quotient less than 0.7; * Patient is a current smoker or an ex-smoker with a smoking history of ≥10 pack-years; * Patient belongs to any of these treatment groups: * Patient is treated by a monotherapy long-acting bronchodilator (Long-Acting Muscarinic Antagonist or Long-Acting Beta Agonist), or * Naïve COPD patient, defined as: * Patient is newly diagnosed, or * Patient is naïve to maintenance therapy, or * Patient is treated with short acting bronchodilators as rescue medication, or * Patient has not been treated with long acting bronchodilators in the last 3 months. Exclusion Criteria: \- Patients should not be included in the study if any of the following exclusion criteria applies: * Patient changed COPD treatment regimen over the preceding 3 months; * Patient treated or intended to be treated at the time of randomisation with a maintenance regimen of inhaled corticosteroids or inhaled corticosteroids-containing medications; * Patient treated or intended to be treated at the time of randomisation with aclidinium bromide/formoterol fumarate dihydrate inhalation powder; * Patient had a previous diagnosis of asthma or is suspected of having asthma, asthma-COPD overlap or any other chronic respiratory disease other than COPD (including severe ones, such as cystic fibrosis, pulmonary fibrosis, active neoplasm except adequately treated \[no evidence of recurrence within 5 years\], active tuberculosis); * Patient developed a respiratory tract infection or COPD exacerbation within 6 weeks (or 3 months if an exacerbation-related hospitalisation was required) before the randomisation visit; * Patient with a history of hypersensitivity reaction to inhaled anticholinergics, sympathomimetic amines, lactose monohydrate, inhaled medication, or any component thereof (including report of paradoxical bronchospasm); * Patient has been previously enrolled in the current study. * Any condition that in the Investigator's opinion, would limit a patient's ability to participate in the study.