Efficacy and Safety of Roflumilast in Patients With Asthma (BY217/M2-012)

Main Inclusion Criteria: Persistent bronchial asthma No change in asthma treatment within 4 weeks prior to visit 1 Non-smoker or ex-smoker (for 12 months or longer) Main Exclusion Criteria: Poorly controlled asthma or seasonal asthma History of lower airway infection four weeks prior to visit 1 Chronic obstructive pulmonary disease (COPD) and/or other relevant lung disease Patients using > 8-puffs/day-short-acting bronchodilator (beta-agonists) (more than 3 days per week on average) prior to visit 1 Clinically relevant abnormal laboratory values suggesting an undiagnosed disease, severe renal insufficiency, active hepatitis or an HIV infection Diagnosis, treatment or remission of any cancer (other than basal cell carcinoma) within two years prior to visit 1 Patients with chronic heart failure Suspected hypersensitivity and/or contraindication to roflumilast or albuterol/salbutamol Female patients of childbearing potential not using adequate means of birth control or pregnant or breast-feeding females Patients who have received any investigational medication or device in the month prior to visit 1 or who plan to use another investigational medication during the study