The ongoing opioid epidemic in the United States
impacts lives on both a personal and national level.
More than 10 million people abused opioids in 2017,
with more than 47,000 opioid-related deaths — a
nearly six-fold increase since 1999. Opioid vaccines
could offer advantages over current treatment options.
When an opioid enters the bloodstream (top), it crosses into the brain, where it
can act on the target receptor to cause psychotropic effects, addiction, and overdose. Opioid
vaccines (bottom) trigger the body to create antibodies that bind to opioid molecules and
prevent them from entering the central nervous system, thus preventing negative effects
Opioid vaccines will likely have a wide range of social and economic effects that
could impact the individual.
Treat at-risk patients. Unlike some current treatment options,
opioid vaccines do not carry the risk of abuse. This could allow for
more effective treatment of patients at high risk of abusing another
medication, such as methadone.
■ Medical advantages. The vaccines have a long duration (months to
years) of action and require limited medical supervision.
■ Compatible with other therapies. Vaccines currently in
development are targeted to illicit use of opioids such as heroin and
fentanyl, and therefore do not interfere with most drug treatment or
pain management therapies.
■ Protection against accidental exposure. Vaccines could be
administered prophylactically to individuals at risk of accidental
exposure to opioids, such as law enforcement, military, and first
■ Lack of broad-based effect. Current opioid vaccines are designed
against the specific chemical structure of each opioid; therefore,
multiple vaccines would be needed to provide broad-spectrum
immunity. In addition, opioids such as fentanyl can be easily altered
into a series of similar molecules called analogs, further complicating
■ Less effective in immune-compromised patients. Patients with
opioid use disorders often have other infections and altered immune
responses that may limit the effectiveness of vaccines.
■ Mechanism not well understood. The current biological
mechanism of opioid vaccines is not as well understood as that of
vaccines for infectious diseases.
■ Patient consent. Consent issues could arise for people who might
receive an opioid vaccine. For example, some might question
a parent's right to compel their child to take a vaccine against a
non-infectious agent, or an addicted person's ability to understand
potential long-term effects of an opioid vaccine.
■ Interference with medical care. If vaccines were developed
against legal opioids that are used for pain management, vaccinated
individuals would have a reduced risk of addiction but would also be
unable to use those medications as effective treatments.
■ Insurance and payment. Recent refusals to provide insurance to
individuals who carry naloxone, used to counter opioid overdose,
highlight the insurance issues surrounding opioid-related treatments.
Would insurance cover an opioid vaccine? What might be the
What is it? Opioid vaccines are medical therapies designed to block
opioids, such as heroin and fentanyl, from entering the brain or spinal
cord, thus preventing addiction and other negative effects. While none are
approved for use yet, they could be useful for at-risk individuals, patients
in drug recovery programs, or first responders who might accidentally
come into contact with deadly opioids that can be absorbed through
the skin. This approach offers advantages over some current treatment
methods, including requiring minimal medical supervision and no
potential for abuse.
How does it work? When opioid molecules bind to receptors in the
central nervous system (the brain and spinal cord), they can cause
psychotropic effects (e.g., hallucination, euphoria), addiction, and
overdose. Opioid molecules have specific chemical structures. Opioid
vaccines are designed to trigger an immune response to these structures
when injected into a patient. Similar to vaccines for infectious diseases,
such as polio or measles, when a patient is treated with an opioid vaccine,
their immune system learns to identify the targeted opioid as a dangerous
foreign substance so it can respond if that opioid enters the bloodstream
in the future.
After the body has learned to target an opioid molecule, it naturally forms
antibodies that can bind to it. These opioid-specific antibodies stick to
opioid molecules in the bloodstream, forming a unit that is too large to
enter the central nervous system.
Without entering the central nervous system, the molecule is not able to
produce the negative effects associated with opioids. The antibody-bound
opioid will eventually be excreted via urine without harming the exposed
How mature is it? As of 2019, the Food and Drug Administration (FDA)
has not approved any opioid vaccines for use. While opioid vaccine
studies were initially proposed as early as the 1970s, clinical trials have
thus far been unsuccessful. Currently, at least three early-stage clinical
trials of potential opioid vaccines are underway, including one that the
Walter Reed Army Institute of Research is conducting on a heroin vaccine.
Recently the National Institutes of Health and the National Institute of
Allergy and Infectious Diseases released a broad agency announcement
to fund the development of opioid vaccines against heroin and fentanyl.
This funding is set to begin in August 2020. Other academic researchers
continue to publish studies focusing on development and preclinical
testing of opioid vaccines.