Researchers at the U.S. Military HIV Research Program at the Walter Reed Army Institute of Research announced Monday some success with an experimental vaccine to block heroin's addictive effects on the brain.
The drug works by inducing the immune system to create antibodies which will bind with heroin, blocking it from crossing the blood-brain barrier, EurekaAlert reports. The experimental results have shown some success with mice and rats, according to a study published in the Journal of Medical Chemistry.
"By eliciting antibodies that bind with heroin in the blood, the vaccine aims to block the euphoria and addictive effects," said Dr. Gary Matyas, Chief of Adjuvants and Formulations for the program. "We hope to give people a window so they can overcome their addiction."
The vaccine also showed some success binding with other frequently abused opioids, like hydrocodone, oxycodone, hydromorphone, oxymorphone and codeine. It may further dampen the impact of of high doses of heroin, meaning it could act to prevent overdoses.
Importantly, the vaccine's antibodies did not interact with drugs like methadone, buprenorphine, and naltrexone, which are used to prevent the symptoms of opioid withdrawal as part of treatment for detoxing opioid addicts. They also did not interact with naloxone (a.k.a. Narcan), a drug commonly administered by emergency medical professionals to reverse the effects of heroin overdose.
Notably, the antibodies did not bind to fentanyl or its analog sufentanil, both of which are substantially more powerful than heroin. Fentanyl was the leading cause of drug overdose deaths in 2016. The antibodies also did not bind to non-narcotic pain relievers like aspirin or ibuprofen.
Although the study is far from conclusive, Matyas was positive about the possible future application of the vaccine for fighting the opioid epidemic, helping to mitigate symptoms of addiction and withdrawal.
"Although we are still in the early phase, this study suggests that vaccination can be used together with standard therapies to prevent the withdrawal and craving symptoms associated with opioid withdrawal," he said.
This is not the first time that a vaccine for opioids has been explored by researchers. In June, Newsweek highlighted a similar vaccine from the Scripps Research Institute, where scientists found success after eight years of research on rats and rhesus monkeys.