Dr Wai Liu is a Senior Research Fellow at St George’s, University of London, who has been investigating medical cannabinoids and their potential anticancer properties.
Dr Liu led a small research group at St Bartholomew’s Hospital investigating the anticancer properties in 2001. Anecdotal evidence presented to him suggested that cannabis could improve the responses to some therapies in patients with cancer. This led to more research studying the anticancer effects of cannabidiol (better known as CBD) in a variety of cancer types used both alone and in combination with other treatment modalities.
According to the research at St George’s, cannabinoids – the active chemicals in cannabis – have been confirmed to contain anticancer properties and are the most beneficial when combined with chemotherapy drugs.
I caught up with Dr Liu at event on medical cannabinoids and brain tumours in London, organised by our Member Charity brainstrust, and asked him a few questions so we could bring some more useful information to our community on this topical subject.
Does the research point towards CBD needing THC (tetrahydrocannabinol – the psychoactive constituent of cannabis) element in order to be effective for brain tumours?
Dr Liu: This is not so clear. There is no doubt that in the lab, THC has anticancer action. In a similar way, CBD has too. Using the two together seems to result in good activity, but the level of action is not necessarily synergistic, thus I suspect the two compounds do not actually require each other to work effectively.
You suggested in your research that it will never be the case of CBD alone - brain tumour trials need to allow for multiple agents in combination (such as chemotherapy drugs) ... which is so hard to design in terms of a trial. Is that correct?
Dr Liu: Depending on the questions asked, combination trials can be relatively straightforward. For example, if you test only two drugs – the arms of the trials may be something like Drug A without CBD and Drug A with CBD.
What clinical trials are currently taking place, any plans linked to brain tumours?
Dr Liu: Very few – an up-to-date list will be on the Clinical Trials website.
Are clinicians prescribing CBD as part of the treatment for brain tumours? What are the barriers for brain tumour patients accessing CBD?
Dr Liu: Some clinicians are prescribing CBD, but this would not be on the NHS and so would be quite expensive. Apart from this way, it can be difficult to get official CBD from doctors.
The fundamental barrier for patients is the lack of full clinical trials confirming activity in patients. Without this ‘badge’, clinicians will rarely prescribe something that has no official clinical value. Once the trials in the UK are completed, depending upon results, access will almost certainly improve.
We know that some clinicians are advocating for medical cannabinoids to be prescribed as a standard for brain tumour patients to treat headaches and seizures, as well any cancer-related side effects – are there plans to expand guidelines so patients can readily access medical cannabinoids?
Dr Liu: Not sure; but it seems sensible that a drug that can help should be made available to patients that could benefit from using it. I understand there has to be legislation to ensure safety, but time is of the essence!
We thank Dr Liu for his time and answering my questions.
The research priorities at our Centres of Excellence are based on finding ways to innovate new curative treatments for brain tumours which will likely have the best outcomes for patients.
We are not currently funding any research into cannabinoids but recognise that the use of these for the management of brain tumours is an important topic and we will continue to closely monitor the ongoing developments in this area, including contributing to governmental Inquiries and consultations where possible.
Image credit: St George’s, University of London