Around 45,000 Kiwis receive support to reduce their alcohol and drug use each year - and that's estimated to be just a third of those having problems. Photo / 123RF
A New Zealand scientist is exploring a new vaccine for drug addiction, which would teach our immune system to reject specific drugs before they could trigger highs.
Researchers have been trying, unsuccessfully, to create such an intervention since the 1970s.
Dr Benjamin Compton believed the failures didn't owe to the concept itself, but to the design of the actual vaccines.
The Victoria University chemistry researcher - who has already helped developed immunotherapy treatments for cancer, asthma, influenza and malaria - aims to create a synthetic vaccine that works in a completely different way to others so far trialled.
The New Zealand Drug Foundation reports 45,000 New Zealanders receive support to reduce their alcohol and drug use each year – and that is estimated to be just a third of those experiencing problems with their use.
The Ministry of Health puts the cost of drug harm and interventions at $1.8 billion.
Working with immunologist Dr Lisa Connor, Compton plans to pioneer a vaccine platform capable of generating an immune response to small drug-like compounds. If successful, the vaccine would avoid the need to rely on using protein to activate the immune system.
The ultimate goal is to be able to instruct the immune system to recognise a specific drug when it enters the bloodstream and to treat it like a toxin.
This means antibodies would bind to the targeted drug in the periphery and prevent it from crossing the blood-brain barrier where it would normally interact with receptors and cause a high.
"Achieving this would herald a new paradigm in immunopharmacotherapy," said Compton, who just received a $150,000 grant from the Health Research Council for the work.
"And importantly, we're aiming to design a vaccine that can be manufactured en masse, at low cost."
Vaccines were one of the most cost-effective and powerful health interventions available, Compton said, and he believed it should be possible to vaccinate against drug addiction.
"Ultimately what we're trying to do is generate a robust B-cell response - an antibody response - to specific drug targets."
Traditionally, this was done by first generating a response from T-cells - those white cells that defend us against infection and disease - which in turn enhanced the B-cell response.
However, because of the complexity of the human body, generating the desired T-cell response could be tricky.
Cellular processing and presentation of proteins varied from person to person which, in part, might have been responsible for past failures to develop vaccines for drugs of abuse.
Compton expects his novel vaccine should improve the T-cell response or, even better, directly activate B-cells independent of a T-cell response.
But even if his vaccine can activate B-cells directly, that in itself might not be enough – and the key to making this kind of vaccine effective is to ensure it also drives a memory response to the drug.
"We are trying to understand the simplest way to activate B cells so that we can invoke a memory response to compounds which would otherwise not be recognised by the immune system."
Compton would initially test his vaccine on mice, and, if he could prove the concept worked, it could be revolutionary.
"This technology will be really helpful for those addicts who want to break free of their addiction. Should that person come into contact with the drug, a vaccine will ensure there is no reward from the drug-taking behaviour."
Health Research Council chief executive Professor Kath McPherson said the research addressed a major issue of concern for individual and public health.
"Drug addiction is a serious problem worldwide, which not only results in personal harm, death and reduced quality of life, but also costs our health system hugely in hospital admissions and emergency attendances, treatment and counselling," she said.
"A vaccine could well be the way of the future. If Dr Compton can deliver proof of concept, it could be a ground-breaking step towards developing a vaccine in the future."
Meanwhile, another of the council's 15 Explorer Grants has gone to a top cancer researcher who hopes to pioneer an implanted device that could routinely detect early-stage cancer.
Professor Parry Guilford, a cancer genetics and biology expert at the University of Otago, has proposed an "indwelling device" which carries the potential to transform cancer survival.
The device would be inserted into the body and left there for a period of time, so it could pick up a new generation of tell-tale cancer "biomarkers" called circulating tumour DNA, or ctDNA.
These markers are not only able to reveal traces of cancer with incredible specificity, but can also pick up most cancer types.
However, its sensitivity is modest for early stage disease, due to the small number of ctDNA molecules that can be purified from a standard 8ml blood draw.
"It works well for late-stage disease, but lacks the sensitivity to find cancer at an early stage, when cure by surgery is still possible," Guilford explains.
"We propose to develop an indwelling device that will capture greater than 36 fold more ctDNA over a 30-minute period enabling this technology to routinely detect early-stage cancer.
"We think it will allow the majority of tumours to be diagnosed while they are still small enough to be cured by surgery."