A new vaccine may be able to totally block the effects of fentanyl — potentially saving thousands of Americans from overdoses each year.
Researchers at the University of Houston, in Texas, developed a shot that was able to stop the extremely potent drug from entering the brains of rats.
Fentanyl binds to opioid receptors in areas of the brain that control pain and emotions. During an overdose, the brain is starved of oxygen, which kills off neurons.
The shot was able to block the drug from entering the brain without affecting other painkillers like morphine, meaning a vaccinated person could still be treated with other drugs if needed.
The vaccine works by stimulating T-cells in the immune system to create antibodies which bind to fentanyl in the bloodstream.
These immune proteins catch the drug as it enters the body and prevent it from spreading further and causing harm. It then gets processed in the kidney and flushed from the body.
Researchers told DailyMail.com the vaccine could be used by people suffering from opioid use disorder or college students who experiment with illicit substances.
Fentanyl was developed as a painkiller to be used in hospitals but its cheap manufacturing costs and high potency has made it a favorable cutting agent for drug dealers.
Meth, cocaine and street Xanax are just some of the drugs that are being laced with fentanyl. Just 2milligrams — the equivalent of five grains of salt — of fentanyl is enough to cause an overdose.
America is currently in the midst of a fentanyl epidemic, with around 200 Americans dying from the synthetic opioid every day. To put that in context, Covid is currently responsible for around 290 deaths per day, according to most recent official data.
Researchers developed a three-shot vaccine that leads to the formation of fentanyl antibodies in a person’s bloodstream. These antibodies can prevent the drug from reaching the brain and totally negate it. This, in turn, stops overdoses
Fentanyl has overrun some American communities, and was responsible for 71,000 drug overdose deaths in 2021. Pictured: A homeless man in Seattle, Washington, smokes fentanyl
Houston researchers hope their vaccine could severely tide the nation’s drug overdose crises and save the lives of thousands.
They are aiming to begin phase 1 human trials for the vaccine next year.
‘When you get a vaccine, we’re usually vaccinating people against [viruses], but here we are vaccinated a person against a chemical,’ Dr Colin Haile, lead researchers and professor at the University of Houston, told DailyMail.com.
Dr Haile notes the body creates antibodies to drugs like fentanyl on its own – though not enough to totally negate it.
Published last month in the journal Pharmaceuticals, researchers tested their vaccine in 60 rats, 28 of which were given the shots.
The rats were vaccinated with three doses – one every three weeks – before being exposed to fentanyl.
Dr Haile explained that the vaccine worked by targeting a molecule that serves as the backbone of the opioid.
The shot uses a fentanyl conjugate – an altered form of the drug’s molecule – as its base.
It then trains the body to generate antibodies capable of fighting off molecules that make up the drug.
‘When an individual gets the vaccine, they get antibodies against fentanyl,’ he said.
‘The antibodies will bind to the drug and keep it from getting to the brain. If you prevent fentanyl from entering the brain you prevent it from producing euphoric effects and effects that lead to overdose deaths.’
The vaccine uses an adjuvants – an ingredient used in some vaccines that helps create a stronger immune response.
They target specific components of the body’s immune response, so that protection against disease is stronger and lasts longer.
They slow the spread of foreign invaders in the body by reducing the rate at which they proliferate in the blood stream.
This vaccines uses dmLT as an adjuvant. The substance boosts the amount of mucous secreted by the immune system.
The above graph shows the CDC estimates for the number of deaths triggered by drug overdoses every year across the United States. It reveals figures have now reached a record high, and are surging on the last three years
Opioids including fentanyl (black line) were behind almost three in five fatalities from a drug overdose, CDC figures showed. The black opioids line includes deaths from synthetic opioids (brown) natural and semi-synthetic opioids (green), heroin (blue), and methadone (purple)
Drug overdose deaths in America are largely concentrated in the Appalachian region
The Houston researchers took blood samples from the rodents who were vaccinated to determine their antibody levels after each shot.
They found a significant jump in antibody levels between weeks four and six, and then consistent protection from the fourth week until the tenth and final week of the study.
‘If you prevent fentanyl from entering the brain you prevent it from producing euphoric effects and effects that lead to overdose deaths.’
Fentanyl binds to receptors in the brain, causing a feeling of numbness, euphoria and sedation.
Over time it diminishes the receptors sensitivity, eventually leading to the opioids being the only way a person can reach those feelings. This leads to addiction.
When a person overdoses their breathing may stop, depriving the brain and other parts of the body oxygen. As a result, a person will suffer severe brain injury.
This can often be deadly. Even survivors will often have permanent brain damage.
Naxolone, sold under the brand name Narcan, is the most effective tool doctors and first responders have against an overdose.
The fast-acting nasal spray quickly clears up the opioid receptors on a person’s brain and undoes the effects of the drug.
It can only be used in the time immediately after an overdose, though. This vaccine can prevent the overdose all together.
Scientists used experiments to gauge how the rats would react to pain to whether the fentanyl had been negated in their blood stream.
Opioids like fentanyl work by creating a feeling called analgesia – the inability to feel pain.
Each of the mice in both study groups were given doses of fentanyl – 0.05 milligrams for every kilogram of their weight (mg/kg or a smaller 0.1mg/kg dose.
If the vaccine is effective, then the pain-negating effects of fentanyl would not be present in rats who received the shots.
Researchers conducted two tests – one which involves applying heat to the rats’ tails to see if they reacted. The method is known as a the tail-flick test, and if the animal removes their tail from the heat, it indicates they can feel pain.
A second experiment saw the rats placed on a heating plate as it was warmed up. If a rodent lifted its legs off of the plate, then they judged to be in pain.
In both tests, the unvaccinated rats did not react to the pain, signaling the fentanyl had a numbing effect on the receptors in their brains.
Vaccinated rats reacted as expected to the pain stimulus, though, showing the painkiller was cancelled out.
Tests on brain samples also revealed that no traces of the drug.
‘It’s as if they never got fentanyl at all. Complete blockade,’ Dr Haile said.
When further tests were run using other painkillers like morphine and oxycodone, the vaccinated rats showed signs of pani.
‘The anti-fentanyl antibodies were specific to fentanyl and a fentanyl derivative and did not cross-react with other opioids, such as morphine,’ Dr Haile explained.
That means a vaccinated person would still be able to be treated for pain relief with other opioids.
Dr Haile’s team have high hopes for the vaccine, if it proves to be successful.
He said it could be used for people addicted to illicit drugs who run the risk of accidentally using fentanyl.
Dr Haile used the example of a parent forcing their child to get vaccinated before going off to college to protect them in case they ‘experiment’.
Some notable cases of fentanyl overdose include rapper Mac Miller, who died of an overdose in 2018, and pop singer Prince, who died in 2016.
Illicit versions of the drug are largely sourced from Mexico via China, with experts pointing out that the southern border crisis is the main way they are trafficked into America.
