Evaluation of GW406381 in Treating Adults With Osteoarthritis Of The Knee

Inclusion criteria: * Subjects have a primary diagnosis of osteoarthritis of the knee with symptom duration of at least 3 months. * Use pain medication, such as a COX-2 inhibitor or NSAID (non-steroidal anti-inflammatory drug) at least 5 days per week. Exclusion criteria: * History of hypersensitivity or intolerance to pain medications. * History of gastroduodenal perforations and/or obstructions. * History of upper GI (gastrointestinal) ulceration within the previous 6 months. * History of upper or lower GI bleeding within the previous year. * History of inflammatory bowel disease. * Currently take sucralfate or misoprostol. * Currently taking aspirin daily for the heart. * Other restrictions around the use medications apply and would need to be discussed. * History of coronary artery disease, (angina, MI) or surgery. * History of congestive heart failure or renal artery stenosis. * History of stroke or transient ischemic attack. * History of uncontrolled hypertension.