Safety, Toleration and Efficacy of Single Inhaled Doses of PF-00610355 in Chronic Obstructive Pulmonary (COPD) Patients.

Inclusion Criteria: * Post-bronchodilator FEV1/ FVC ratio of \<0.7. * Post bronchodilator FEV1 of 50-80% (inclusive) of predicted. * Body Mass Index (BMI) of less than 35 kg/m2; and a total body weight greater that 40 kg. * Current smokers, or ex-smokers who have abstained from smoking for at least 6 months. Exclusion Criteria: * Subjects having more than 2 exacerbations requiring treatment with oral steroids or hospitalization for the treatment of COPD in the previous year. * History of lower respiratory tract infection or significant disease instability during the month preceding screening or during the period between screening and randomization.