Impact of cannabis-based drug on aggressive brain tumours to be studied in UK trial

A British trial hopes to establish whether a cannabis-based drug could help extend the lives of those diagnosed with aggressive brain tumours.

Brain tumours are the biggest cancer killer of people under the age of 40, and around 2,200 people are told they have a glioblastoma – the most aggressive form – every year in England alone. The typical prognosis is 12 to 18 months from the date of first diagnosis.

The new trial hopes to look at whether using Sativex – an oral spray containing cannabinoids – in conjunction with chemotherapy could extend the overall length of glioblastoma patients’ lives, delay the progression of their disease, or improve their quality of life.

Some 232 patients at 15 hospitals across the UK are due to be recruited early next year if the trial goes ahead.

However, with the Brain Tumour Charity’s income having dropped by 25 per cent due to the pandemic, it has launched an appeal to help raise £450,000 needed to fund the three-year trial.

Sativex can currently only be prescribed on the NHS for people with multiple sclerosis-related spasticity. If the trial were to prove successful, researchers say it would represent one of the first new treatments for glioblastoma added to the NHS since temozolomide chemotherapy in 2007.

Almost all glioblastomas recur even after intensive treatment including surgery, radiotherapy and chemotherapy, with an average life expectancy of 10 months after the tumour first recurs following initial surgery or treatment.

Over the last decade, there has been significant global interest within both patient and scientific communities about the activity of cannabinoids in brain tumours, with patients sometimes seeking various forms of medical cannabis products illicitly.

While several pre-clinical laboratory studies have suggested that cannabinoids THC and CBD may reduce brain tumour cell growth and could disrupt the blood supply to tumours – there has so far been limited clinical evidence that they could treat brain tumours.

In phase one trials earlier this year, the drug was found to be tolerable in recurrent glioblastoma patients already receiving temozolomide.

While more patients who received Sativex were still alive after one year compared to those given placebos, that phase of the trial was not sufficiently geared towards establishing survival rates to draw firm conclusions. Ten out of 12 patients receiving Sativex survived the year, compared to 4 out of 9 patients in the placebo arm.

If phase two trials are able to go ahead, two-thirds of participants will be given Sativex, and a third given a placebo, up to 12 times per day, with regular check-ups. They will receive monthly clinical assessments, blood tests and MRI scans every eight weeks, and will also complete quality of life questionnaires.

Stephen Lee, 62 from Leyland in Lancashire, was first diagnosed with glioblastoma in 2010, just a few months after losing his older brother to the same disease. In 2015, he took part in the phase one trial after his cancer returned following initial treatment.

“My diagnosis was very sudden and was one of those days you never forget,” Mr Lee said. “Having had to leave work early with a severe headache and a stabbing pain in my right eye, my wife insisted that we go straight to hospital after what my brother had experienced.

“I was admitted that same day, had a scan and that’s when they identified it was a brain tumour. I had the operation the following week, and beforehand my wife and I agreed that we wanted to stay positive, to keep living our lives and to enjoy however much time we had together.”

Mr Lee joined the early trial of Sativex in the hope it could improve his quality of life, but said he “thought it only right and proper” that he followed in the footsteps of those who had taken part in the trials of the chemotherapy and radiotherapy he himself was receiving.

“I took the oral spray 10 times a day, and it was easy as I could take it wherever we were going, even while out for dinner. While I don’t know whether I had Sativex or the placebo, since the trial finished in 2016, all my MRI scans have been clear,” Mr Lee said.

"This new trial is so important as it will give people hope that there could be life beyond a glioblastoma diagnosis and that there are other treatments being trialled to support them to live their lives.”

The study will be led by an expert at the University of Leeds and coordinated by the Cancer Research UK Clinical Trials Unit at the University of Birmingham.

Dr David Jenkinson, interim chief executive at The Brain Tumour Charity, said: “We hope this trial could pave the way for a long-awaited new lifeline that could help offer glioblastoma patients precious extra months to live and make memories with their loved ones.

“We know there is significant interest among our community about the potential activity of cannabinoids in treating glioblastomas, and we’re really excited that this world-first trial here in the UK could help accelerate these answers.”

Pointing to the “really promising” early-stage findings, Dr Jenkinson added: “But we also know that for many, this trial won’t come soon enough.

“In the meantime, while other cannabis-based products may help alleviate symptoms, there is insufficient evidence to recommend their use to help treat brain tumours. For anyone considering using cannabis-based products or other complementary therapies, it’s vital that you discuss these with your medical team first, as they could interact with other treatments such as anti-epileptic medicines or steroids.”