Placebo to match CHF6001 DPI

A 52-week, randomized, double-blind, placebo-controlled, parallel-group, study to evaluate the efficacy and safety of two doses of CHF6001 DPI add-on to maintenance triple therapy in subjects with Chronic Obstructive Pulmonary Disease (COPD) and Chronic Bronchitis.

A 52-week, randomized, double-blind, double-dummy, placebo- and active- controlled (Roflumilast, Daliresp® 500μg), parallel group, study to evaluate the efficacy and safety of two doses of CHF6001 DPI add-on to maintenance triple therapy in subjects with Chronic Obstructive Pulmonary Disease (COPD) and chronic bronchitis