An implant to blunt opioid effects

A slow-release naltrexone implant helps HIV patients with opioid dependence adhere to medications and prevent relapse.

When patients with HIV who are also battling opioid dependence go without addiction treatment, they are more likely to stop taking their HIV medications than drug-free patients. While the daily oral form of naltrexone—a drug that blunts the effects of opioids—is one option to treat opioid dependence, medication adherence among drug users is known to be low. A new study, published in Lancet HIV by Penn Medicine researchers, shows that a naltrexone implant placed under the skin, which slowly releases the drug over three months, was more effective at helping HIV-positive patients with an opioid addiction reduce relapse and have better HIV-related outcomes compared to the oral drug.

gloved hand holding naltrexone implant

The study was conducted in Russia where oral, extended-release injectable and implantable naltrexone products are approved, but medications such as methadone or buprenorphine are against the law. Those medications activate the same neurological receptors as opioids, and some critics view the approach as exchanging one drug addiction for another. Naltrexone has been approved by the U.S. Food and Drug Administration since the 1970s, however the only commercially available forms are the 50 mg tablet and an extended-release injectable product that blocks opioid effects for a month.

“The findings have implications for treatment of opioid dependence among patients that do not want agonist maintenance or who live in places where options are more limited,” says senior author George E. Woody, an emeritus professor of psychiatry at the Perelman School of Medicine. “Further development and formal approval of these implants in a wider range of cultural settings has the potential to provide an effective and meaningful HIV and opioid treatment option for these patients.”

Read more at Penn Medicine News.