Safety and Efficacy of Buprenorphine Transdermal System in Subjects With Moderate to Severe Osteoarthritis of Hip or Knee

The Time (Days) From First Administration of Double-blind Treatment to the Development of Inadequate Analgesia at the Primary Osteoarthritis Pain Site.

Inadequate analgesia: * "average pain over the last 24 hours" score for pain at primary osteoarthritis (OA) site ≥ 5 on any 2 days of any 7-day dosing period, on a scale from 0 - 10 (0 = no pain to 10 = pain as bad as you can imagine)or; * \>1000 mg/day acetaminophen for pain at primary OA site for ≥ 2 days in any 7-day dosing period, or; * ingested nonstudy opioid analgesic medication for pain at primary OA site. Score: lowest score = shortest time to inadequate analgesia; highest score = longest time to inadequate analgesia.

Time frame: Double-blind phase ( 28 days): reaching "inadequate analgesia" on any 2 days of the 7-day dosing periods