The purpose of this study is to determine whether inhalation of Bimosiamose is safe and effective in the treatment of patients with moderate to severe Chronic Obstructive Pulmonary Disease (COPD)

Inclusion Criteria:

• Male and postmenopausal or sterile female patients with a history of moderate to severe COPD defined as Global Initiative for Chronic Obstructive Lung Disease (GOLD) II-III for at least 1 year
• At least 40 years of age
• Current smoker or ex-smoker with at least 10 pack-year smoking history (Ten pack-years is defined as 20 cigarettes a day for 10 years, or 10 cigarettes a day for 20 years etc.)
• Postbronchodilator FEV1 between 30% and 80% predicted and FEV1/FVC ratio < 70%. Postbronchodilator refers to 30 min after inhalation of 400 µg Salbutamol. This criterion for FEV1 will have to be demonstrated after a washout period of at least 48 h during which no long acting anticholinergic medication (LAMA) or long acting β2-agonists (LABA) has been inhaled or a washout period of 6 h during which no short acting β2-agonists (SABA) or anticholinergic medication (SAMA) has been inhaled. For patients having been pretreated with an inhaled corticosteroid (ICS) and/or theophylline, this criterion needs to be demonstrated after a washout of at least 4 weeks.
• Able to produce sputum upon induction in a sufficient quality. This criterion will be checked by the responsible sputum lab prior to randomization of the patient.
• Time and ability to complete the study
• Able to communicate well with the investigator, to understand and comply with the requirements of the study. Understand and sign the written informed consent.

Exclusion Criteria:

• Patients with a history of chronic respiratory disorders other than COPD e.g. asthma, α1-Antitrypsin deficiency, mucoviscidosis, lung fibrosis
• Patients who experienced an exacerbation in the 4 weeks before the screening visit or between screening and randomization
• Patients who experienced an acute upper respiratory tract infection or broncho-pulmonary infection requiring antibiotic treatment during the 4 weeks before the screening visit or between screening and randomization
• Treatment with inhaled (ICS), topical or any systemic corticosteroids or theophylline within at least 4 weeks before the screening visit and throughout entire course of the study. Patients with ICS and/or theophylline treatment will undergo a washout of at least 4 weeks after signature of the informed consent and prior to the screening visit, where eligibility to enter the study will be assessed