Researchers at Oxford University are to lead a research programme into the antipsychotic properties of cannabidiol (CBD).
CBD is one of the chemicals found in marijuana but it is distinct from tetrahydrocannabinol (THC), the chemical in marijuana which produces the feeling of being high. £16.5 million has been awarded to the department of psychiatry at Oxford University by the Wellcome Trust. This money will be put towards a global clinical trial to see if CBD can treat people with psychosis.
Currently, the NHS only prescribes CBD for a few conditions such as severe epilepsy in children and vomiting and nausea in adults caused by chemotherapy.
Professor Philip McGuire of Oxford university will lead the Stratification and Treatment in Early Psychosis (Step) programme. It will involve 1000 people who are either at clinically high risk of psychosis, are undergoing a first psychotic episode or have psychosis and have not responded to conventional treatment.
Professor McGuire said: “Cannabidiol is one of the most promising new treatments for people with psychosis. Many people with psychosis are open to trying cannabidiol and previous smaller-scale studies have indicated that it has beneficial effects.
“As well as treating psychosis that is already established, the study will also investigate whether cannabidiol can prevent the onset of psychosis in people at high risk of developing it.”
Since they were developed in the 1950s, drugs such as quetiapine and olanzapine have often been used to treat psychosis by blocking dopamine receptors in the brain. However, these antipsychotics are ineffective for many that use them, and the side effects associated with them can be severe. But for most living with psychosis, there are no alternatives. Research into CBD as an antipsychotic would therefore be welcomed.
Lynsey Bilsland, head of mental health translation at Wellcome, said: “This exciting programme will help us to find out if cannabidiol is effective at treating psychosis at various stages by testing it at scale.
“While antipsychotics are commonly used to treat psychosis, they can have significant side effects, patients often stop taking them, and they don’t work for everyone. This means that it is important that we explore avenues such as this one for new therapies.
“In addition, as part of these trials the researchers are aiming to identify biomarkers – biological signposts – which would indicate that a patient might respond well to the treatment. This will allow for greater personalisation of treatment in the future.”
The programme will be coordinated from Oxford and will involve 35 centres across Europe and North America, with the CBD being provided by Jazz Pharmaceuticals at no extra cost.