The University of Leeds is set to lead a new three-year Phase II clinical trial in the UK to evaluate the use of a cannabis-based drug, Sativex, to treat aggressive brain tumours.

An oromucosal spray, Sativex consists of two cannabinoids, namely tetrahydrocannabinol (THC) and cannabidiol (CBD). Produced by GW Pharma , the drug is currently used to treat multiple sclerosis.

To be coordinated by the University of Birmingham’s Cancer Research UK Clinical Trials Unit, the Phase II trial will be funded by the Brain Tumour Charity.

Named ARISTOCRAT, the trial will be conducted at 15 National Health Service (NHS) hospitals in more than 230 patients across the UK.

It will investigate the efficacy of Sativex plus temozolomide chemotherapy in extending life for patients with recurrent glioblastoma, which currently has an average survival of under ten months.

ARISTOCRAT is based on favourable results from a 27-patient Phase I trial conducted earlier this year. Data showed that the drug was tolerable when given with chemotherapy and has the potential to improve survival.

In the Phase I trial, more subjects in the Sativex group were alive after one year versus those in the placebo arm. However, the university noted that the study was not adequately powered to demonstrate survival impact.

The first-of-its-kind Phase II trial is scheduled to commence enrolment early next year, contingent on raising necessary funds.

If the trial is successful, Sativex can potentially be one of the first additions to NHS for treating glioblastoma patients since temozolomide in 2007.

University of Leeds clinical oncology and neuro-oncology professor Susan Short said: “The treatment of glioblastomas remains extremely challenging. Even with surgery, radiotherapy and chemotherapy, nearly all of these brain tumours re-grow within a year, and unfortunately, there are very few options for patients once this occurs.

“Glioblastoma brain tumours have been shown to have receptors to cannabinoids on their cell surfaces, and laboratory studies on glioblastoma cells have shown these drugs may slow tumour growth and work particularly well when used with temozolomide.”

Findings from multiple pre-clinical laboratory studies indicated that THC and CBD could decrease the growth of brain tumour cells and hinder the blood supply to tumours.

But clinical evidence on these cannabinoids’ ability to treat brain tumours has been minimal so far.