Australian scientists have found a way to hinder the pleasurable effects of cocaine by targeting a receptor that also plays a role in heroin addiction.
A research team from Adelaide and the US has been testing a new medication, called plus naloxone, for the past eight years. In previous studies on mice, they found it could block the pleasurable properties of opioids, including morphine and heroin.
Now they have discovered it also works with cocaine.
"We are gradually working through the abused drugs," said professor Mark Hutchinson of the University of Adelaide. "We've now shown in animal studies that plus naloxone is able to stop the rewarding properties of morphine and heroin. We also know it reduces alcohol's rewarding effects, and it looks like it's doing the same thing with amphetamines and now cocaine.
"What that means is all of these drugs of abuse that we knew had multiple mechanisms to create rewarding properties, we now think we've found that one linchpin that holds them all together."
The study, published in the Nature journal Molecular Psychiatry, describes the role of the immune receptor known as toll-like receptor 4.
"Our previous studies have shown that TLR4 is responsible for amplifying addiction to opioid drugs, but this is the first time we've discovered it has a key role to play in cocaine addiction," Hutchinson said. "We've taken the data we've got from opioids to the US Department of Defense and they got excited. They're sponsoring it to go into clinical trials."
The team expects the treatment to undergo trials in the US. Hutchinson emphasised that addictions were complex and required both medical and psychological treatment. He added that the drugs showed the potential to take the edge off cravings and withdrawals.
"We don't know for cocaine, but what we do know for opioids is that it blunts the withdrawal."
Australia ranks fourth in the world for cocaine abuse.
Do you have an idea for a story?
Email [email protected]