Oxycodone/naloxone PR versus oxycodone PR in advanced cancer: A multi-centre randomised trial (ENhANCE trial)

Area of Science:

• Oncology
• Pharmacology
• Pain Management

Background:

• Opioid-induced constipation is a frequent adverse effect of oxycodone, impacting patient quality of life.
• While Oxycodone/Naloxone Prolonged Release (OXN PR) is effective for non-cancer pain, its efficacy in advanced cancer patients remains under-investigated.

Purpose of the Study:

• To establish the non-inferiority of OXN PR compared to Oxycodone Prolonged Release (Oxy PR) in terms of analgesic effectiveness.
• To determine the superiority of OXN PR in alleviating constipation among patients with advanced cancer pain.

Main Methods:

• A multi-centre, open-label, randomized controlled trial was conducted over 5 weeks.
• Participants with moderate-to-severe pain (≥4/10) from advanced cancer were enrolled.
• The study compared OXN PR against Oxy PR, assessing pain reduction and bowel function.

Main Results:

• The study, though stopped early due to COVID-19 enrollment challenges, demonstrated analgesic non-inferiority for OXN PR versus Oxy PR.
• The OXN PR group showed a statistically significant reduction in constipation, evidenced by a lower Bowel Function Index score (p=0.03).
• The safety profile of OXN PR was more favorable compared to Oxy PR.

Conclusions:

• OXN PR is a viable alternative to Oxy PR for managing advanced cancer pain, offering equivalent pain relief.
• OXN PR demonstrates superior efficacy in mitigating opioid-induced constipation.
• These findings support OXN PR as a recommended opioid preparation for advanced cancer patients, with potential for naloxone combination in other opioid formulations.