It feels like we’re living in a golden age of vaccine science at the moment. There are the frankly incredible achievements that are the COVID-19 vaccines – from “hmm there’s this new disease going around in Wuhan, you think we should keep an eye on it?” to over three billion people at least partially vaccinated in less than two years – but there are also a few HIV vaccines on the horizon, and even one for the plague being trialed in the UK.
But one vaccine, now being trialed at Columbia University, is a little different. It doesn’t guard against a virus or bacteria, but addiction: opioid addiction, to be exact. Instead of treating opioid use disorders with medication or therapy alone, future opioid users may be able to take a simple – albeit temporary – vaccine to help kick the habit.
“We have good medications to treat opioid use disorder, but about half of the people who use these medications relapse after about six months,” explained Sandra Comer, professor of neurobiology and principal investigator of the trial. “A vaccine that lasts for several months, given in combination with any of these medications, could help many more people beat their addiction and potentially protect them from an overdose death if a patient relapses.”
The vaccine works like any vaccine: by triggering the body’s immune system to create antibodies. But instead of attacking a virus protein like with many other vaccines, these antibodies go for oxycodone, the prescription opioid painkiller abused by more than 13 million Americans. Put simply, the antibodies attach themselves to the oxycodone molecules and stop them from crossing the blood-brain barrier. No drug getting into the brain means no high – and no high means no addiction.
“Vaccine development has been a tremendous [boon] to humanity,” Columbia University Psychiatry chair Jeffrey A. Lieberman said. “This innovative work brings it to bear on the scourge of addiction with the hope of having a great impact.”
For now, the vaccine is in the phase 1a/1b clinical trial stage; administering the treatment to a small number of human participants to evaluate its safety and efficacy. But it’s already shown promise in pre-clinical trials, where vaccinated animals reduced their opioid intake voluntarily and were protected against toxicity and overdosing. While the study is ongoing, another team at the University of Minnesota will be monitoring blood samples from participants to better understand how the vaccine works.
The US has long been in the clutches of an opioid addiction epidemic, with approximately 100,000 hospitalizations every year stemming from painkiller misuse. Opioid overdoses accounted for nearly 50,000 deaths in 2019 alone, prompting researchers to try everything from weed to brain implants to combat the crisis. This new experimental vaccine isn’t the first to be designed against the epidemic, but it is the first to reach human trials in the US, according to the researchers.
There’s just one problem – or, depending on how you look at it, an advantage. Different opioids have different chemical structures, so unlike vaccines that combat viruses, this particular vaccine won’t help against anything except oxycodone abuse. Other opioids, like heroin or the fatally popular fentanyl, will need separate vaccines. While that sounds bad, it does come with a big benefit: it means that opioid-based medications such as naloxone, which is used to resuscitate patients who have overdosed, won’t be affected by the vaccine.
“Clinicians would be able to give the oxycodone vaccine to individuals who mainly use that particular drug but could also administer additional opioid vaccines for … other opioids,” explained Comer. “A fentanyl vaccine could also be used to protect first responders, law enforcement, or soldiers if they inadvertently inhale carfentanil, which can be fatal in very small doses.”