A Study To Investigate Whether PF-04457845 Is Effective In Treating Pain, Is Safe And Tolerable In Patients With Osteoarthritis Of The Knee

A Phase 2a Randomized, Double-blinded, Double Dummy, Placebo And Active Controlled, Two-way Cross-over, Flare-enriched Multi-centre Clinical Trial To Examine The Pain Relief Produced By 2 Weeks Of Daily Oral Administration Of A Fatty Acid Amide Hydrolase (Faah) Inhibitor Pf-04457845 In Patients With Osteoarthritis Of The Knee.

Inactivation of the FAAH (Fatty Acid Amide Hydrolase) enzyme has been shown to relieve pain and inflammation in animal studies. PF-04457845 has been shown to inactivate the FAAH enzyme in animals and healthy human volunteers. The purpose of this study is to evaluate whether PF-04457845 can inactivate the FAAH enzyme in patients experiencing pain due to OA and whether this results in these patients experiencing less pain.

Inclusion Criteria:

• Subjects must have a diagnosis of Osteoarthritis (OA) of the knee confirmed by X-ray
• Subjects must be willing and able to stop all current pain therapy for the duration of study. (Limited and specific pain therapy will be available throughout the study)
• Subjects can be male or female between the ages of 18 and 75 years inclusive, but female subjects must not be able become pregnant

Exclusion Criteria:

• Subjects must not have any condition or medical history that might interfere with their ability to complete the study assessments