Inclusion Criteria:  Male or female adults aged ≥40 years; Signed informed consent; Current or ex-smokers with a smoking history of at least 10 pack years. An ex smoker will be defined as a subject who has not smoked for ≥ 6months at screening; Diagnosis of COPD according to the International Statement; COPD patients with a forced expiratory volume in the 1st second (FEV1) between 30% and 80% of predicted post-bronchodilator (salbutamol 400 µg) at baseline visit; COPD patients with lung hyperinflation with residual volume (RV) ≥ 120% predicted; COPD patients treated with ICS/LABA or LABA/LAMA or ICS/LAMA therapy from at least one month before baseline visit; COPD patients with elevated impact of disease and/or symptoms defined by a CAT≥ 10 score and/or a mMRC ≥ 2 score and an history of exacerbation (≥ 1 exacerbation in the previous year).  Exclusion Criteria:  Patients with COPD exacerbation that required treatment with antibiotics, systemic steroids (oral or intravenous) or hospitalization in the 4 weeks prior to enrolment; Patients with concomitant other lung disease (e.g. asthma, lung fibrosis, primary bronchiectasis, sarcoidosis, interstitial lung disorder, pulmonary hypertension); Patients requiring long-term oxygen therapy (LTOT) ≥12 h a day on a daily basis for chronic hypoxemia; Patients with severe comorbidities associated to COPD, such as unstable cardiovascular diseases or cancer; Patients with narrow-angle glaucoma, symptomatic benign prostatic hyperplasia (BPH), bladder-neck obstruction, moderate to severe renal impairment or urinary retention. BPH patients who are stable on treatment will be considered for enrolment; Patients with clinically significant renal, cardiovascular (such as but not limited to unstable ischemic heart disease, New York Heart Association (NYHA) Class III/IV left ventricular failure, myocardial infarction), neurological, endocrine, immunological, psychiatric, gastrointestinal, hepatic, or haematological abnormalities which could interfere with the assessment of the efficacy and safety of the study treatment; COPD patients treated with triple LABA/LAMA/ICS therapy; Pregnant women; Subjects unable to meet the criteria of acceptability and repeatability of pulmonary function tests, according to the American Thoracic Society/European Respiratory Society (ATS/ERS) document.