Human trials move a step closer for opioid overdose vaccine

They will begin human trials soon

“We anticipate testing our vaccines in humans in early 2024,” said Dr. Jay Evans, director at the UM Center for Translational Medicine at UMT, in a press statement.

“The first vaccine will target heroin, followed shortly thereafter with a fentanyl vaccine in Phase I 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.”

Fentanyl and other opioid drugs are causing one of the worst drug crises in countries like the U.S. Fentanyl is a synthetic opioid that is up to 50 times stronger than heroin and 100 times stronger than morphine.

In the U.S., over 106,000 deaths were reported due to drug overdose in 2021, according to the National Institutes of Health. Of those, 71,000 can be attributed to synthetic opioids like fentanyl.

“Our vaccines are designed to neutralize the target opioid, while sparing critical medications such as methadone, buprenorphine, naltrexone, and naloxone, which are used in treatment of opioid addiction and reversal of overdose,” said Dr. Marco Pravetoni, a professor of psychiatry and behavioral sciences at the University of Washington.

Pravetoni’s team has been working on opioid vaccines for the last 10 years and designs haptens, which, when combined with a larger carrier such as a protein, can elicit the production of opioid antibodies.

The University of Montana’s contribution comes in the form of a patented adjuvant called INI-4001, which, when added to the vaccine cocktails, boosts the effectiveness of vaccines.

“Our adjuvants improve the vaccine response, providing a stronger and more durable immunity,” added 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.”

Heroin vaccine trials to begin before fentanyl

The vaccines were tested using the animal model, which was successful. Mice were tested at UMT, and rats and pigs at the University of Minnesota. Additionally, a paper demonstrating the success of the fentanyl vaccine was published in July this year. However, the publication on the success of the heroin vaccine is forthcoming.

That said, even though the Fentanyl paper was published first, Dr. Evans believes that the heroin vaccine trials will begin first.

“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 researchers highlighted that the Phase 1 human trials will be conducted at Columbia University in New York City. It could take up to six months to recruit people who use fentanyl or heroin.

“We start with the lowest dose – a dose that may not be effective,” said Dr. Evans. “Phase I 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.”

A vaccine for an opioid overdose would be beneficial not only to the people who partake in opioid consumption, medically or recreationally but also to its silent victims. Especially in cases of opioid drug misuse, it gravely affects the families of those who are addicted. Non-medical usage can result in social exclusion, stigma, and mental stress.