Oxytrex: an oxycodone and ultra-low-dose naltrexone formulation.

Abstract

Oxytrex (Pain Therapeutics, Inc.) is an oral opioid that combines a therapeutic amount of oxycodone with an ultra-low dose of the antagonist naltrexone. Animal data indicate that this combination minimizes the development of physical dependence and analgesic tolerance while prolonging analgesia. Oxytrex is in late-stage clinical development by Pain Therapeutics for the treatment of moderate-to-severe chronic pain. To evaluate the safety and efficacy of the oxycodone/naltrexone combination, three clinical studies have been conducted, one in healthy volunteers and the other two in patients with chronic pain. The putative mechanism of ultra-low-dose naltrexone is to prevent an alteration in G-protein coupling by opioid receptors that is associated with opioid tolerance and dependence. Opioid agonists are initially inhibitory but become excitatory through constant opioid receptor activity. The agonist/antagonist combination of Oxytrex may reduce the conversion from an inhibitory to an excitatory receptor, thereby decreasing the development of tolerance and physical dependence.

• Authors: Lynn R Webster
• Journal: Expert opinion on investigational drugs (Expert Opin Investig Drugs) Vol. 16 Issue 8 Pg. 1277-83 (Aug 2007) ISSN: 1744-7658 [Electronic] England
• PMID: 17685875 (Publication Type: Journal Article, Review)

Chemical References

• Oxytrex
• Naltrexone
• Oxycodone

Topics

• Animals
• Chemistry, Pharmaceutical
• Dose-Response Relationship, Drug
• Drug Administration Schedule
• Humans
• Naltrexone (administration & dosage, chemistry)
• Oxycodone (administration & dosage, chemistry)