Naloxone, a medication for opioid addiction, works by blocking the effects of opioid receptors on the body. While it has been shown to protect against infection, its safety under conditions of abuse has been unknown. The researchers sought to determine strengths in the oral naloxone dose-finding regimen to minimize potentially unsafe doses.
During this double-blinded placebo-controlled trial, participants were exposed to varying doses of either naloxone or placebo by mouth, injecting either 1 or 6 times daily. This dose was increased following each dose, and then decreased, the next day. Study investigators also evaluated the effect of naloxone in terms of sexual dysfunction of non-habitual users, and CGI scores. On the study’s seventh day, patients were evaluated for soreness, nausea, and gastrointestinal disorders in a proportion of each group capacity based on their global assessment of sexual dysfunction.
Three weeks after the first dose of naloxone, oral naloxone dose-finding showed little difference in the pain principle at one, six, and one-month follow-ups compared with placebo in the sexual dysfunction test and CGI score, and there was no difference in the non-sexual dysfunctions score. No clinically significant differences were seen in the placebo-naloxone dosing regimen at any of the time points compared with naloxone in the oral naloxone dose-finding trial.
The study findings suggest that oral naloxone may be a safe option for the treatment of opioid addiction in humans, including patients who have an opioid dependence. The findings may also apply to translational projects meant to modify current opioid dependence in case of safe and effective oral naloxone formulations.
“We have been implementing naloxone randomised clinical trials to address opioid addiction in humans and have no experience of safety risks for a major part of the population,” said Rishi Sahni, principal investigator from Therapeutics Research & Development Ltd, a Nusrati consortium lead for the study. “Because naloxone is taken by mouth, it appears that naloxone may have a role in treatment of opioid addiction.”