Fentanyl, Heroin Vaccines to Enter Phase 1 Trials Soon

MISSOULA, MT — Researchers at the University of Montana (UM) and their partners are nearing human trials for vaccines to prevent fentanyl and heroin drug overdoses. The vaccines would protect people struggling with drug addiction or those at risk of accidental overdose. According to the National Institutes of Health, more than 106,000 US drug overdose deaths were reported in 2021. Of those, 71,000 can be attributed to synthetic opioids like fentanyl.

Researcher Jay Evans, PhD, director of the UM Center for Translational Medicine and co-founder of an MT-based biotech company, Inimmune, said, “We anticipate testing our vaccines in humans in early 2024.” 

“The first vaccine will target heroin, followed shortly thereafter with a fentanyl vaccine in Phase 1 clinical trials. Once we establish safety and early efficacy in these first clinical trials, we hope to advance a combined multivalent vaccine targeting both heroin and fentanyl,” Evans said.

Marco Pravetoni, PhD, professor of psychiatry and behavioral sciences at the University of Washington and director of the Center for Medication Development for Substance Use Disorders, and his research team design haptens and drug conjugate vaccines that can elicit the production of antibodies against target opioids. “Our vaccines are designed to neutralize the target opioid while sparing critical medications such as methadone, buprenorphine, naltrexone, and naloxone, which are used in the treatment of opioid addiction and reversal of overdose,” Pravetoni said.

The UM team contributes a patented adjuvant, called INI-4001, to the vaccine cocktails. Adjuvants are substances that boost the effectiveness of vaccines. “Our adjuvants improve the vaccine response, providing a stronger and more durable immunity,” said Evans. “We have worked closely with researchers from Inimmune, the University of Minnesota, the University of Washington, Hennepin Healthcare Research Institute and Columbia University over the past few years to design and optimize anti-opioid vaccines for advancement to human clinical trials.”

When will the vaccines enter clinical trials?

The vaccines were tested with animal models to support their advancement to human clinical trials. Papers demonstrating how the TLR7/8 adjuvant increased the effectiveness of the fentanyl vaccine among animals were published recently in NPJ Vaccines. Publications on the success of the heroin vaccine are forthcoming.

There are many moving pieces in vaccine development, and Evans expects the heroin vaccine human trials to begin before the fentanyl, even though the fentanyl papers were published first. The team expects to finalize their Investigational New Drug applications to the FDA later this year. “The human clinical trials will include a drug challenge to evaluate both safety and efficacy of the vaccines in early clinical development,” he said. “We will also follow the patients to evaluate how long the antibodies against opioids will last.”

The Phase 1 human trials will be conducted with Sandra Comer, PhD, at Columbia University, NY. Evans said it could take six months or longer to recruit and enroll the required subjects: people who are using fentanyl or heroin. The Phase 1 trials will involve gradual dose escalation. “We start with the lowest dose—a dose that may not be effective,” Evans said. “Phase 1 clinical trials are focused on safety. When the first dose cohort is complete, a data safety monitoring board reviews the data and approves testing at the next dose level if the vaccine is safe. The process takes time until you reach dose levels that are both safe and effective.”

The road ahead

After that, Phase 2 human trials determine things like the number of doses needed to be effective and the amount of time required between doses. Phase 3 is the all-important efficacy study that involves many participants that the FDA uses to determine whether the benefits of the vaccine outweigh the potential risks.

Evans said Inimmune and the University of Washington are working on the process development and scale-up manufacturing of GMPs to produce the volumes and quality of vaccine products necessary for Phase 1 human trials.  

In addition to the anti-opioid vaccines, the UM team is working on vaccines targeting SARS-CoV-2, the influenza virus, tuberculosis, monkeypox, pertussis, pseudomonas, Lyme disease, valley fever, malaria, E. coli, allergy, and cancer. “We expect to see other vaccine candidates advance to Phase 1 clinical trials in the coming years,” Evans said. “Some are new vaccines, and others are improved versions of current vaccines with adjuvants added to increase vaccine safety, durability, and efficacy in vulnerable populations.”

- This press release was originally published on the University of Montana website