Oxytrex: an oxycodone and ultra-low-dose naltrexone formulation.
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.
Webster
Lynn R
LR
Lifetree Clinical Research and Pain Clinic, Salt Lake City, Utah, USA. lynnw@lifetreepain.com
D000818:Animals; D002626:Chemistry, Pharmaceutical; D004305:Dose-Response Relationship, Drug; D004334:Drug Administration Schedule; D006801:Humans; D009271:Naltrexone / Q000008:administration & dosage* / Q000737:chemistry*; D010098:Oxycodone / Q000008:administration & dosage* / Q000737:chemistry*
C503788:Oxytrex; D009271:Naltrexone; D010098:Oxycodone