Scientists from the Scripps Research Institute have just published the results of a study done on a special kind of vaccine in the journal Angewandte Chemie. This vaccine does not guard against a virus. Instead, it blocks the effects of synthetic designer drugs. Fentanyl is an opioid that moves from the blood to the brain, where it binds to opiate receptors. The immediate result is pain relief, but fentanyl also increases the brain's dopamine level, which brings on a feeling of euphoria. Fentanyl often gets mixed in with illegal drugs to increase their effects; it also increases the chances that someone will overdose and die. And because fentanyl is popular, a number of different fentanyl derivatives have sprung up around the world. The new vaccine may block them all.
The vaccine contains molecules that are structurally like fentanyl -- and invites the immune system to take them down. Eventually, the body's immune system recognises fentanyl and its derivatives as an invader, and antibodies bind to the drug as soon as it enters the bloodstream -- preventing it from getting to the brain. If fentanyl can't get to the brain, it can't get people high. The vaccine seems to be selective, causing the immune system to block variations on fentanyl, but not oxycodone. While that still leaves the user open to oxycodone abuse, it also gives them an option if, sometime after the vaccination, they need pain relief.
The vaccine is meant to reduce overdoses due to fentanyl derivatives by blocking the high that people get, and therefore stopping them from seeking out the drug in the first place. Naturally, this raised concerns about someone taking fentanyl, not feeling high, and taking more -- which would lead to an overdose.
In this case, however, the antibodies blocking the drug from getting to the brain also prevent lethal overdoses. "To the best of our knowledge," said Atsushi Kimishima, a co-author of the study, "our active vaccine is the first to ablate lethal doses of any drug of abuse."
The researchers hope to expand their vaccine so it will block the effects of heroin as well.