Buprenorphine Transdermal System (BTDS) in Subjects w/Mod-sev Osteoarthritis (OA) Chronic Pain of Knee

Inclusion Criteria: * subjects with moderate to severe chronic osteoarthritis (OA) pain of the knee (lasting several hours daily) as their predominant pain condition, * clinical diagnosis of OA of the knee 1 year or longer, * subjects treated within the 14 days prior to screening with nonopioid therapy only, or with therapy including opioids at a dose of \< 5 mg oxycodone (or equivalent) per day, * subjects whose OA knee pain is not adequately controlled with nonopioid analgesic medication and who the investigator feels are appropriate candidates for around-the-clock opioid therapy. Exclusion Criteria: * subjects who have had arthroscopy on either knee or hip within 6 months of entering the study or open surgery on either knee or hip within 9 months of entering the study, * subjects who are allergic to buprenorphine or who have a history of allergies to other opioids, * subjects who have allergies or other contraindications to transdermal delivery systems or patch adhesives. Other protocol-specific inclusion/exclusion criteria may apply.