Researchers find anti-gout drug that lessens pain of opioid withdrawal in mice

Opioid withdrawal eased in mice by anti-gout drug

CALGARY — A study identifying one of the underlying causes of opioid withdrawal has singled out an anti-gout drug as possibly easing the suffering associated with overcoming addiction.

Scientists at the University of Calgary published research in the journal Nature Medicine on Monday showing that the medication probenecid is effective at reducing the severity of withdrawal symptoms in mice that are addicted to morphine or fentanyl.

Lead researcher Tuan Trang at the Hotchkiss Brain Institute and the university’s school of veterinary medicine said the findings could eventually help people overcome an addiction to opioids by alleviating the “adverse and debilitating” experience of withdrawal.

While the “million-dollar question” remains how well the findings will translate from mice to humans, Trang said the study enhances researchers’ understanding of the mechanism of withdrawal and establishes a good starting point to identify candidate drugs to treat the condition in people.

The research focused on microglia, a type of immune cell located in the brain and spinal cord that was found to be associated with withdrawal.

“It gives us a new potential therapeutic target,” said Trang.

The study found that suppressing microglia cells in rodents experiencing opioid withdrawal significantly reduces their negative symptoms.

“So it could be another drug that we could use in combination with some of the existing therapies to help an individual get past this episode of withdrawal and maybe help them get off of opioids,” Trang said.

Gout is a type of arthritis caused by increased levels of uric acid in the bloodstream, which produces acute joint pain, often in the base of the big toe.

Health Canada has already approved the drug to treat gout, which he said could be an advantage.

“It makes it easier for us then to gain approval for a new use for treating opioid withdrawal as opposed to a brand new compound that we then have to go through all the testing for how it works and the safety of it.”

Still, expanding the use of a pre-approved drug requires additional regulatory approval, which could take years, Trang said

Preparation is underway for a clinical trial involving a small group of human patients to be conducted in collaboration with the Calgary Pain Clinic.

“Right now we’re at the very, very early stages in terms of assembling the team, in terms of making sure that the trial is very stringent, that it’s safe,” Trang said.

The University of Toronto, the University of Laval in Quebec and the University of California, Irvine, all contributed to the research, he said.

— By Geordon Omand in Vancouver

The Canadian Press

Canadian Press