Trending Clinical Topic: Fentanyl Vaccine

Ryan Syrek


December 23, 2022

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When it comes to the ongoing opioid epidemic, good news is hard to come by. Last year alone, the United States hit a record high with more than 107,000 drug overdose deaths, most involving fentanyl. Worldwide, about 500,000 deaths are attributed to drug use annually, with more than 70% related to opioids. That helps explain why recent news out of Texas was met with such enthusiasm and widespread interest (see Infographic).

Researchers say that the vaccine prevents fentanyl from entering the brain. "Thus, the individual will not feel the euphoric effects and can 'get back on the wagon' to sobriety," lead investigator Colin Haile, MD, PhD, said in a news release. "The anti-fentanyl antibodies were specific to fentanyl and a fentanyl derivative and did not cross-react with other opioids, such as morphine. That means a vaccinated person would still be able to be treated for pain relief with other opioids," said Haile. Also encouraging was the fact that no adverse effects were observed. Human trials are in the planning stages, as the research team intends to manufacture clinical-grade vaccine in the coming months.

This new tool can't come soon enough. A recent research letter explained that that drug overdose deaths in the United States among pregnant and postpartum women rose by around 81% from 2017 to 2020. In the study period, 1249 of the 7642 pregnancy-related deaths in the study period were overdose-related, leading to a cumulative overdose death rate of 8.35 per 100,000 population. From 2017 to 2020, pregnancy-related overdose deaths rose from 6.56 to 11.85 per 100,000. That translates to an absolute change rate of 5.30 per 100,000 and a relative increase of 81%. Researchers found substantial increases in deaths involving fentanyl. Pregnancy-associated overdose deaths involving benzodiazepines, heroin, and prescription opioids were mostly stable over the same period.

Making things more complicated, fentanyl now contaminates most of other drugs of misuse, with many individuals becoming addicted unknowingly. They may believe they are ingesting cocaine, oxycodone, or another drug and unknowingly find themselves exposed to fentanyl. This is particularly problematic given that the high potency of fentanyl can overcome the opioid blockade of methadone and buprenorphine. In one recent study, nearly half of overdose deaths involving fentanyl were found to have occurred before the body had a chance to produce norfentanyl, a process that only takes about 2-3 minutes. In the 48 fentanyl deaths studied, no appreciable norfentanyl concentrations were detected in 20 cases (42%); concentrations were less than 1 ng/mL in 25 cases (52%).

This contamination has led some authorities to legalize test strips designed to detect whether fentanyl is in an illicit drug. Pennsylvania recently joined around 30 other states in decriminalizing the test strips. The immunoassays cost around $1 each and give a simple positive or negative indication that fentanyl is in a powder, pill, or injectable. The tests have been considered illegal drug paraphernalia by the Drug Enforcement Administration. Harm-reduction advocates say that removing this restriction has the potential to help reduce overdoses and save lives.

Both inside and outside United States, clinicians continue to confront the ongoing opioid crisis. Although a fentanyl vaccine may still be months to years away from availability, the prospect of the new tool was enough to spark substantial interest. As more interventions and strategies are unveiled, they are likely to be met with equal zeal.

Learn more about opioid toxicity.


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