Prednisolone will be used as a model medication to identify new clinical outcomes for future evaluation of new therapies in short-term studies (up to 4 weeks) in patients with Chronic Obstructive Pulmonary Disease (COPD).

Inclusion Criteria:

• An established clinical history of COPD
• Evidence of bronchitis
• Current or ex-smoker

Exclusion Criteria:

• COPD exacerbation requiring steroid and/or antibiotics in the last month
• Taking oral or inhaled steroids for more than 14 days in the last 6 months
• Unable to withhold salbutamol/albuterol for a 6 hour period
• History of alcohol, substance or drug abuse within the last year.
• Other significant medical condition e.g. diabetes
• Cancer that has not been in complete remission for at least 5 years
• As a result of the medical interview, physical examination or screening investigations, that the doctor considers the subject unfit for the study.