The vaccine has been developed at The Scripps Research Institute (TSRI) and it works against the opioid drugs oxycodone (oxy) and hydrocodone (hydro), tested so far in animal models. Opioids are substances that act on opioid receptors in the brain to produce morphine-like effects. As well as blocking opioids the vaccine could lower the risk of opioid overdose.
Speaking with PharmaPro magazine, the lead researcher, Professor Kim D. Janda explains the action of the vaccine: “We saw both blunting of the drug’s effects and, remarkably, prevention of drug lethality. The protection against overdose death was unforeseen but clearly of enormous potential clinical benefit.”
Professor Janda goes onto explain that the vaccine works in relation to the body’s immune system acting to seek out and eliminate invaders. The basis of the vaccine is an opioid structure with a molecule designed to trigger an immune response. Once injected into the body, the vaccine ‘coaxes’ the immune system to bind to the drug molecule and to remove it from circulation. This action stops any opioid from reaching the brain.
By blocking the path of the opioids to the brain, the vaccine can address the problem of opioid-relate addiction by eliminating the feelings of ‘reward’ and ‘euphoria’ associated with consuming the medication. Unlike other anti-opioid related treatments, the developed vaccine does not alter brain chemistry. The effects of the vaccine lasted for 60 days.
The trials, using mice, also showed that rodents given the vaccine were less prone to a fatal overdose of opioids. Here opioids above a safe level took far longer to exert toxic effects.
The vaccine will need further clinical trials and testing on humans before it becomes available to patients. Some of the developmental work will focus on optimizing the dose level and administration schedule.
The research findings are published in the journal ACS Chemical Biology. The study is titled “An Advance in Prescription Opioid Vaccines: Overdose Mortality Reduction and Extraordinary Alteration of Drug Half-Life.”
