A fentanyl vaccine may be on the horizon

There may soon be a new way to prevent deaths from fentanyl. A preventative vaccine for fentanyl exposure that could prevent the symptoms of overdose is set to begin human trials and could change the landscape of drug overdoses in the U.S.

A stab at a solution

Exposure to even small amounts of the synthetic opioid fentanyl can be deadly, and action to stop an overdose can only happen after the drug has been consumed. Now ARMR Sciences, a New York-based biotechnology company, may have designed a vaccine to counteract fentanyl overdose. “It became very apparent to me that as I assessed the treatment landscape, everything that exists is reactionary,” Collin Gage, the cofounder and CEO of ARMR Sciences, said to Wired. “I thought, why are we not preventing this?”

The new vaccine works differently from naloxone, which is currently used to reverse the effects of drug overdoses. Instead, the vaccine is “similar to a suit of armor,” said The Independent. “Receiving it first will, in theory, protect an individual from danger if they encounter fentanyl.” The shot “pairs a fentanyl-like compound with a deactivated diphtheria protein that kicks the immune system into high gear,” said The Tech Buzz. “When antibodies latch onto fentanyl, they make the drug molecules too large to cross the blood-brain barrier.”

Because the drug would not reach the brain, the vaccine would “prevent the drug from causing respiratory failure and death,” as well as “prevent the extreme highs that come from using fentanyl,” said The Independent. If effective, the vaccine would offer protection for approximately a year.

ARMR Sciences is launching a human trial of the vaccine in the Netherlands next year using 40 healthy adults. It will be conducted in two phases. In the first, volunteers will “receive a series of two shots in varying doses, and researchers will measure their blood antibody levels,” said Wired. In the second, a “small group of participants will receive a medical dose of fentanyl so that investigators can study how well the vaccine blocks its effects.”

A point of contention

This is not the first attempt at an opioid vaccine. One was proposed in the 1970s as a way to combat heroin overdoses. However, that vaccine largely failed, and the research was abandoned. The recent opioid crisis “led to a resurgence of interest, with backing from the U.S. government,” said Wired. In 2023, researchers developed an anti-fentanyl vaccine that worked positively on rats, according to a study published in the journal Pharmaceutics. The ARMR Sciences vaccine is based on this previous vaccine iteration.

Fentanyl is the number one cause of overdose deaths in the U.S., accounting for just over 48,000 deaths in 2024, according to the CDC. Most exposure is accidental, with the synthetic opioid being added to other substances. A vaccine could help the most vulnerable populations, including adolescents and teens, but many are concerned about the safety and effectiveness.

When parents were asked about whether they would get their kids a potential fentanyl vaccine, many were worried it might “interfere with the brain’s natural ‘pleasure and reward’ center and negatively impact mood or the developing adolescent brain,” said a study published in the journal Vaccine. However, “parents who had lost kids to overdose were especially enthusiastic,” Elissa Weitzman, the director of research for Boston Children’s Division of Addiction Medicine and lead author of the study, said in a statement.

Though even if an effective vaccine is made available, it alone will not end the opioid epidemic or stop people from seeking out the drugs. But it could save some lives. “What we’re trying to do is put some innovation and new, newfound technology behind this problem,” Gage said. “I think we’re in desperate need of it.”