The Long-Held Hope for an Opioid Vaccine

As overdose deaths climb during the pandemic, vaccine makers seek a treatment

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COVID-19 is the public health emergency that dominates the headlines, but it isn’t the only one. The opioid epidemic was raging for several years before COVID and is still going strong. Despite numerous years spent addressing the problem, this public health crisis is now worse than ever.

Opioid deaths have risen steadily over the past 20 years. And since the emergence of COVID, abuse and fatalities have only grown faster. Data indicates 93,000 opioid overdose deaths in 2020 compared to 70,000 deaths a year earlier—a 30 percent increase.

This widespread and often deadly addiction may also share something else with COVID: a vaccine may soon be used to treat it.

In September 2021, researchers began the first human trials for an opioid vaccine. It works like a traditional vaccine, in that it prompts the body’s immune system to make antibodies. However, these antibodies aren’t used to block a virus. Instead, they’re designed to block opioid molecules from reaching the brain.

What makes this trial special is that many failed attempts have preceded it. Hopes for an opioid vaccine have been around since the 1970s, although trials until recently have fallen short. Most never made it out of the discovery phase.

But support for the idea has persisted. A 2019 U.S. Government Accountability Office (GAO) report discussing opioid vaccines notes at least three early-stage clinical trials then in development, including one from the Walter Reed Army Institute of Research testing a heroin vaccine. In August 2020, The National Institute of Allergies and Infectious Diseases began funding these projects.

Hopes remain high that an approved opioid vaccine lies just around the corner. However, one of the limitations involved in this strategy is the specificity built into each shot. The one now in human trials, for example, only blocks oxycodone molecules. It doesn’t interfere with other opioids, such as fentanyl or heroin. Proponents of these vaccines say this feature is a benefit, because it leaves the door open for other treatment options in the event a patient might require pain management in the future. However, it also means that multiple vaccines are necessary if patients turn to other opioids when they can no longer get a fix from their favorite.

And there’s a wide spectrum of choices when it comes to opioids, which originated from the opium poppy—a plant at the center of two major wars between Great Britain and China in the 1800s. Since then, the humble poppy has spawned many opium derivatives that are stronger and far more addictive, including OxyContin, morphine, and heroin.

Perhaps the most potent opioid drugs are called fentanyls—a family of synthetics said to be 80 to 100 times stronger than morphine.

Fentanyl’s potential for abuse and fatality is greater as well. According to an analysis of data from the U.S. Centers for Disease Control, fentanyl fatalities have skyrocketed under COVID. From April 2020 to April 2021, more than 64,000 overdose deaths were attributed to fentanyl poisoning—nearly double the same period in 2019. According to Families Against Fentanyl (FAF), the drug has become the No. 1 cause of death for Americans between the ages of 18 and 45.

Due to fentanyl’s capacity to kill, and the enormous quantities that have been smuggled across the U.S. borders in recent years from China and Mexico, some believe it must be taken more seriously. In July, FAF sent a letter to President Joe Biden, urging him to classify fentanyls as weapons of mass destruction.

“The Department of Homeland Security seizes only a fraction of the fentanyls that traffickers attempt to bring into the U.S. Sadly, it is estimated that more than 40,000 Americans died last year from these dangerous chemicals,” the letter states. “The significant presence of illicitly manufactured fentanyls in our cities and neighborhoods places all of us in danger.”

Vaccines for Every Ill

An opioid vaccine may sound strange, because we typically think of vaccines as treatments that provide protection against contagious diseases. But the injection format has expanded to address a range of issues. Vaccines are now in development to fight Alzheimer’s, Parkinson’s, heart disease, allergies, autoimmune disease, and more.

In fact, two companies currently known for creating vaccines for COVID—BioNTech and Moderna—were originally set up to develop vaccines to fight cancer.

Vaccination has been around for more than 200 years, but today, it’s more popular than ever. From the constant messaging urging everyone to get their COVID shot and follow-up boosters, to the slightly less persistent messages to get flu, shingles, and other shots available at your local drug store.

Vaccines are already a major part of modern health care, and their influence is expected to grow even larger. Some see the future treatment of all diseases one day taking the form of a jab. As of April 2020, there were nearly 260 vaccines in development by U.S. drug companies, both to prevent and treat disease.

But will a shot solve the opioid crisis? It isn’t likely. Even the most ardent supporters of the treatment admit it’s no magic bullet. If and when an opioid jab does finally make it to market, it’s at best expected to fill a few gaps left by the other three medications to treat opioid abuse that are already approved by the U.S. Food and Drug Administration: methadone, buprenorphine, and naltrexone. Ideally, the shot would provide some preventative protection when drugs to address overdoses aren’t readily available.

According to the GAO, the protection of a single shot could perhaps last months or even years, and would require little medical supervision.

However, even larger gaps in the strategy to end opioid addiction would still remain. For example, a shot won’t stop the shipments of illegal fentanyl that continue to flood the country, nor can one undo the damage caused by drug companies that aggressively promoted opioid drugs in the 1990s and early 2000s, and misrepresented their potential for abuse. A jab also is unlikely to address the pain and trauma that are typically found behind an addiction.

One question about what the regulatory framework will be for any opioid vaccine that does get approved, since vaccine makers currently enjoy unique protection from financial liability for vaccine injury claims. While a drug maker can be sued and subjected to a class action lawsuit for problems associated with their products, in the United States vaccine makers can’t, due to the National Childhood Vaccine Injury Act passed in 1986 and more recent legislation approved in response to COVID-19.