Opioid analgesics such as morphine continue to play a critical role in chronic cancer and non-cancer pain control. Despite their effectiveness, opioids have significant drawbacks, notably the development of analgesic tolerance and physical dependence, sedation, respiratory depression and bowel dysfunction.
Opioid-induced constipation (OIC) is common, affecting up to 80% of patients receiving opioids for chronic non-cancer pain.
TD-1211 is an investigational, peripherally selective, mu-opioid receptor antagonist designed to alleviate gastrointestinal side effects of opioid therapy without affecting analgesia.
Safety and efficacy results, including the primary and key secondary endpoints, from a 5-week, Phase 2b study in chronic non-cancer pain OIC patients have been previously reported.
Additional assessments on daily pain score, opioid dose, and central opioid withdrawal are reported here to demonstrate that TD-1211 is peripherally selective and does not impact centrally-mediated analgesia.