The purpose of this study is to determine whether long term treatment with oral erythromycin is effective in the treatment of subjects with Chronic Obstructive Pulmonary Disease (COPD) by reducing the number of exacerbations and the degree of airway inflammation.

COPD is characterised by persisting airway inflammation which leads to a progressive and irreversible deterioration in lung function with the eventual development of respiratory symptoms which may become disabling. Periodic episodes of worsening symptoms or exacerbations are a major cause of additional morbidity, mortality and health care utilization. Currently available therapies have limited efficacy in reducing airway inflammation or preventing exacerbations.

Macrolides such as erythromycin have been shown to have potent anti-inflammatory effects in in vitro experiments and in other lung conditions such as cystic fibrosis and bronchiectasis as well as in open label studies in COPD. We hypothesised that long term therapy with oral erythromycin would reduce airway inflammation and reduce the frequency of exacerbations in patients with COPD. If these properties are demonstrated this therapy can have potentially important benefits if effective in this condition.

Inclusion Criteria:

• Clinical Diagnosis of COPD
• Clinically stable for 6 weeks
• Able to Swallow Tablets

Exclusion Criteria:

• Clinically significant respiratory disease other than COPD
• Women of child bearing age
• Patients receiving existing Medication which may interact adversely with trial drug
• History of clinically significant liver disease