Major trial to establish if cannabis drug shrinks brain tumours
Uasin Gishu Deputy County Police Commander Zacchaeus Ng’eno (in uniform), during display of bhang, at Eldoret Police Station. The weed was uprooted by police from a bungalow in the posh Elgon View Estate, Eldoret town of Uasin Gishu County on July 06, 2022. Trial is ongoing to establish if cannabis-based drug Sativex can be used to treat the most aggressive form of brain tumour.
A new major trial of cannabis-based drug Sativex in treating the most aggressive form of brain tumour is ongoing in the United Kingdom across 15 national hospitals.
This comes after medicinal cannabis was legalised in the UK in 2018 and since then, campaigners, researchers, and scientists have been working hard to understand the potential benefits of medicinal cannabis as research has been held back for decades due to the war on narcotic drugs.
Scientists conducting the phase II trials at the University of Leeds seek to assess whether adding Sativex – an oral spray containing cannabinoids THC (Delta-9-tetrahydrocannabinol) and CBD (cannabidiol) – to chemotherapy, could extend life for thousands diagnosed with a recurrent glioblastoma (the most common and most aggressive form of brain cancer, with around 2,200 people diagnosed each year in England alone).
They explain that almost all glioblastomas recur even after intensive treatment, including surgery, radiotherapy and chemotherapy, and average survival is just 12-18 months from first diagnosis.
The researchers further add that 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 – but to date, clinical evidence that they could treat brain tumours has been limited.
“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.
“Having recently shown that a specific cannabinoid combination given by oral spray could be safely added to temozolomide chemotherapy, we’re really excited to build on these findings to assess whether this drug could help glioblastoma patients live longer in a major randomised trial,” said Prof Susan Short, the principal investigator on the trial and professor of Clinical Oncology and Neuro-Oncology at the University of Leeds, adding that 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.”
Average survival
The new three year-phase II trial, led by the professor and coordinated by the Cancer Research UK Clinical Trials Unit at the University of Birmingham, is recruiting more than 230 patients across the UK this year.
After promising results from a phase one study in 27 patients, experts at University of Birmingham say that their phase two trial will “assess whether adding Sativex to chemotherapy could extend life for thousands diagnosed with a recurrent glioblastoma, which currently has an average survival of less than 10 months”.
Sativex, which is already being used in treating multiple sclerosis, was found to be tolerable in combination with chemotherapy, with the potential to extend survival in a phase one trial last year.
The trial observed that more patients who were given Sativex were alive after one year compared to those taking a placebo.
But in this new phase II trial, researchers will assess whether adding Sativex to the current standard chemotherapy treatment (temozolomide) could offer extra time to live for adults diagnosed with a recurrence of their glioblastoma after initial treatment.
The researchers plan to recruit 232 participants across a minimum of 15 hospitals with two thirds of the participants being given temozolomide plus Sativex while one third will be given temozolomide plus placebo.
The drug which was manufactured by GW Pharma, is an oromucosal spray containing 1:1 THC and CBD with the active ingredients being absorbed in the lining of the mouth, either under the tongue or inside the cheek according to the makers of the drug.
Regular follow-up
“Participants will be asked to administer up to 12 sprays per day (or to the maximum dose they can tolerate if fewer than 12) of Sativex or placebo oral sprays.
They will then undergo regular follow-up including clinical assessment (every four weeks), blood tests, MRI scans (every eight weeks), and they will complete quality of life questionnaires,” they observe, adding that potential side effects as noted during phase one trials include fatigue, headache, vomiting and nausea.
In January 2019, the World Health Organisation (WHO) Director General Tedros Ghebreyesus made a series of recommendations to the United Nations to update the scope of control of cannabis and cannabis-related substances.
The global health regulator pointed out that these new recommendations reflect the emerging therapeutic role of cannabis-based medicines whilst continuing to prevent diversion, misuse, and other public health-related harms that may arise from cannabis use.
