The Scripps Research Institute of La Jolla announced Tuesday that a vaccine it developed effectively blocks the “high” of heroin in nonhuman primates, based on testing by scientists in Virginia.
The TSRI vaccine is the first targeting an opioid to pass the stage of pre-clinical testing.
“This validates our previous rodent data and positions our vaccine in a favorable light for anticipated clinical evaluation,” said study leader Kim Janda, a professor of chemistry and member of the Skaggs Institute for Chemical Biology at TSRI. He said the vaccine should be safe for human trials.
This research was published recently in the Journal of the American Chemical Society. The primate experiments were led by researchers at Virginia Commonwealth University.
The vaccine works by exposing the immune system to a part of the heroin molecule’s structure, which teaches the immune system to produce antibodies against heroin and its psychoactive products. The antibodies neutralize heroin molecules, blocking them from reaching the brain to cause a feeling of euphoria.
Researchers believe that blocking the high of heroin will help eliminate the motivation for many recovering addicts to relapse into drug use. In recent years, public health officials around the world have labeled heroin use as an epidemic.
The researchers at Virginia Commonwealth, in Richmond, gave three doses each, of varying levels, to four rhesus monkeys. They said the vaccine was effective at each dose level and didn’t produce apparent negative side effects.
Two of the monkeys had received the same vaccine seven months prior, part of an earlier study. The scientists said that paid showed a higher level of response this time around, showing a sort of immune system memory.
If the same effect occurs in humans, addicts would have a long-term immunity against heroin addiction.
The vaccine candidate works only against heroin and not other opioid-based painkillers or medications for treating opioid addiction or overdose, leaving those open for use in emergency medical situations, and for prescription medicines and substance use disorders, the scientists said.
The next step in this research will be to license the vaccine to an outside company for partnering in clinical trials.
The study was funded by the National Institutes of Health and Skaggs Institute for Chemical Biology.
— City News Service