Safety of BTDS in Subjects With Osteoarthritic (OA) Pain of Hip or Knee: A 6-Month Open-label Extension Phase

Inclusion Criteria: * Subjects with moderate to severe osteoarthritic (OA) pain who completed all visits of the double-blind phase on study drug, or who discontinued study drug due to lack of therapeutic effect in the double-blind phase, but still completed all visits of the double-blind phase off study drug, are eligible to enroll in the extension phase. Exclusion Criteria: * Excluded from the study are subjects who ingest \> 2500 mg/day acetaminophen as part of their current stable nonopioid analgesic regimen. * Subjects requiring long-acting opioid analgesics \[once- or twice-daily dosing with an every (q) 24 hour (h) or q12h drug\] or transdermal fentanyl during the extension phase should be discontinued from the study. Refer to core study for additional inclusion/exclusion information.