The primary purpose of this study is to evaluate the pharmacodynamics of single oral doses of PF-05175157 in healthy volunteers

Inclusion Criteria:

• Healthy male and/or female subjects between the ages of 18 and 55 years, inclusive.
• Healthy is defined as no clinically relevant abnormalities identified by a detailed medical history, full physical examination, including blood pressure and pulse rate measurement, 12 lead ECG and clinical laboratory tests.
• In addition, subjects must have normal pulmonary function tests and normal ocular examination.
• Body Mass Index of 20.0 35.0 kg/m2; and a total body weight >50 kg (110 lbs).

Exclusion Criteria:

• Evidence or history of clinically significant hematological, renal, endocrine, gastrointestinal, cardiovascular, hepatic, psychiatric, neurologic, or allergic disease (including drug allergies, but excluding untreated, asymptomatic, seasonal allergies at time of dosing).
• Evidence or history of any chronic ongoing or current pulmonary disease.
• History of smoking in the past 5 years or history or evidence of habitual use of other (non smoked) tobacco or nicotine-containing products within 3 months of Screening or positive cotinine test at Screening or Day 0.
• Active ocular disease including infection, glaucoma, seasonal allergies, dry eye symptoms or retinal/optic nerve disease.