Effect of Switching From Cigarette Smoking to THS on Disease Progression in Mild to Moderate COPD Subjects With Chronic Bronchitis Symptoms.

Main Inclusion Criteria: * Subjects have read, understood, and signed the written informed consent form (ICF) * Diagnosis of COPD GOLD Stage 1 or 2 (FEV1/FVC \<0.70 \& FEV1 ≥60% predicted \[post-BD\]) * Current symptoms of chronic bronchitis (sputum and cough) based on CAT questionnaire scores for CAT1 (cough) item ≥ 3 and CAT2 (sputum) item ≥ 3 * Body mass index (BMI) 17.6-40.0 kg/m2 and body weight \> 50 kg (male) or 40 kg (female). * Subject has a smoking history of at least 10 years. * Subject has been smoking ≥ 10 commercially available cigarettes/day on average (no brand restriction) for at least 1 year prior to V1 (based on self-reporting). * Subject has not used other tobacco and nicotine products apart from cigarettes on a daily basis over the past year prior to V1. * For subjects not willing to quit smoking only: have been advised to quit smoking, informed of smoking risks and of cessation programs and is still not willing to quit during the study duration. * Subjects willing to quit smoking only: willing to set a target quit date (TQD) within the next 28 days at V1 as assessed by self-reported questions. Main Exclusion Criteria: * Subjects with any (mild, moderate or severe) COPD exacerbation that has not resolved at least four weeks prior to V1 * Subjects with active cancer or history of any cancer * Subjects with pneumonia or other lower respiratory tract infections that have not resolved at least four weeks prior to V1 * Subjects with other active systemic in…