Marseille's Timone University Hospital to experiment with synthetic cannabis for Parkinson's patients

The Dhune Center of Excellence at Marseille's Timone University Hospital intends to experiment with synthetic cannabis on Parkinson's patients. The hospital was one of the first in France to obtain authorization to experiment with the effects of synthetic cannabinoids, in particular to reproduce the effects of cannabis on alertness, cognition and driving. We spoke to Professor Olivier Blin, Director of the Center for Clinical Pharmacology and Therapeutic Evaluations, to find out more about this new study.

A study in its infancy

The project is not a direct follow-up to the ANSM's decision to launch an experiment on medical cannabis but is indeed part of a growing interest, in France and internationally, in the potential therapeutic virtues of cannabis. Patients being increasingly inclined to self-administer cannabis with no control, no follow-up and products of unknown composition, it is the Professor's opinion that research must take the lead in providing patients with a safe and verified treatment option.

The study is funded in part by the France Parkinson association and in part by the Dhune neuropôle. It will be conducted by Jean-Philippe Azoulay of the Neurology and Movement Pathology Department, Alexandre Eusebio and Christelle Baunez of the CNRS and La Timone Neuroscience Institute, and the Pharmacology Department of Prof. Olivier Blin.

For the moment, the study is only in the experimental phase: the Professor's clinical pharmacology department is trying to determine the optimal composition of the products to be administered to Parkinson's patients, so as to be able to submit a request for authorization of a clinical trial on patients to the Comité de Protection des Personnes and the ANSM.

Recruitment has not yet begun, but the researchers hope to launch the study before the end of 2019. In general, the committee for the protection of individuals requires that volunteers have already consumed cannabis spontaneously. The researchers plan to recruit around 30 people and administer synthetic cannabinoids (THC and CBD).

Why synthetic cannabinoids?

In addition to the concern for precision, the Professor emphasizes a concern for supply: «the idea is to ensure supply, to be sure that at any time we can have several suppliers in Europe capable of producing the necessary quantities, should it ever become a medicine». Synthetic cannabinoids, whose formula does not differ from natural cannabinoids, can in fact be produced in the laboratory without having to go through the stages of cultivation, harvesting, extraction and processing.

A precise understanding of the interaction between cannabis and Parkinson's disease

Parkinson's disease corresponds to a degeneration of dopaminergic neurons, leading to a lack of dopamine, which in turn causes a loss of plasticity and motivation. We already know that the encannabinoid system and its receptors interact with the dopaminergic system. A cannabinoid-based treatment could therefore potentially stem the degeneration of these neurons, or at least alleviate certain symptoms.

Some testimonials suggest that this is the case. Cannabis has also been shown to combat the loss of plasticity in multiple sclerosis. However, for the professor, it's a question of studying the precise action of cannabinoids on Parkinson's patients, which has probably never been done under rigorous conditions: «We need to reassure patients and be able to give them concrete, measured, objective, controlled elements to determine whether or not it's of interest», he explains.

The aim of this study is therefore to carry out a genuine risk-benefit analysis of Parkinson's symptoms, by determining which motor and non-motor symptoms, for example, are likely to improve with cannabis. This will involve the precise measurement of cannabis concentrations in the blood, so as to establish a link between the product and its effects. The study should also define whether a generic concentration ratio is sufficient, or whether a case-by-case approach is required.

Science versus superstition

Clinical trials of this kind are designed to allay the fears surrounding the use of cannabis in medicine, and to provide a clear-sighted response to the hopes and concerns of patients and healthcare professionals. The aim is to «reassure all those involved by providing irrefutable evidence of the properties and, once again, the benefit/risk ratio», explains Prof. Blin.

«It's good that France is a driving force in this type of study, that beyond the fears sometimes expressed by society or certain people in society about cannabis derivatives or, more generally, molecules with a psychotropic action, we're able to answer questions from patients, government agencies and academics, but above all to know what we can do for patients, which, in my opinion, is the most important thing», he adds.

In 2016, a clinical trial of a synthetic inhibitor of the FAAH enzyme, designed to enhance the action of the endocannabinoid system, caused 1 death and several injuries. Another synthetic inhibitor used to treat obesity was launched by Sanofi in 2008, but withdrawn after a year.