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Epilepsy Ireland welcomes American decision to licence Epidiolex

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Yesterday's decision by the US Food and Drug Administration (FDA) to approve Epidiolex for the treatment of two rare and severe forms of epilepsy is a landmark moment not just for people with epilepsy in the US, but in Ireland and around the world as well.

Epidiolex is a liquid formulation of purified, plant-derived cannabidiol (CBD), a non-psychoactive component of the cannabis plant.

It becomes the first FDA-approved drug that contains a purified drug substance derived from cannabis and is to be licenced for Lennox-Gastaut syndrome and Dravet syndrome, in patients two years of age and older.

The decision follows a number of randomized, double-blind, placebo-controlled clinical trials involving over 500 patients which found Epidiolex to be effective in reducing the frequency of seizures when taken with other epilepsy medications compared with placebo. The drug is currently being reviewed in Europe by the European Medicines Agency and is expected to be approved later in 2018 or early 2019.

Up to 30% of all epilepsy cannot be managed by existing treatments and Epidiolex represents an invaluable new option for some of those individuals in achieving better seizure control. It is especially welcome as the mechanism of action of Epidiolex is completely different to all other epilepsy drugs and gives patients and doctors a new weapon in the ongoing battle against seizures. It may also generate much needed research into other potential cannabis-based treatments (including those containing THC, the psycho-active component in cannabis) in future as well as studies on its effectiveness in more common forms of epilepsy.

In the meantime, we hope that Epidiolex will be made available in Ireland as part of the Government's Medicinal Cannabis Access Scheme. An expert group to establish the Scheme was announced in March 2017 but the Scheme has not yet been established. Yesterday's developments provide a reminder that properly studied, standardised cannabis-based treatments can have a significant impact on improving the quality of life of people currently living with uncontrolled seizures and we urge the Minister or Health to make the long-promised Access programme operational as soon as possible.

While the approval of Epidiolex in the US is a very positive development, there are a number of important points that must be noted.

Firstly, as with any other epilepsy drug, Epidiolex is not a 'magic bullet' and is likely to be an immediate option in only a small number of patients.

Secondly, the approval of Epidiolex in the US does not mean that other formulations of CBD oils and products can be assumed to be effective. The strength of these products can vary from batch to batch and some products purporting to be CBD have been found to contain no CBD at all. As the FDA Commissioner Scott Gottlieb said yesterday, "Because of the adequate and well-controlled clinical studies that supported this approval, prescribers can have confidence in the drug's uniform strength and consistent delivery that support appropriate dosing needed for treating patients with these complex and serious epilepsy syndromes. We'll continue to support rigorous scientific research on the potential medical uses of marijuana-derived products and work with product developers who are interested in bringing patients safe and effective, high quality products. But, at the same time, we are prepared to take action when we see the illegal marketing of CBD-containing products with serious, unproven medical claims".

Similarly, the approval of Epidiolex cannot be taken to mean that THC-containing products are effective in epilepsy. There are currently no studies of comparable scientific rigour on the role of THC and considerable concerns exist about potential side effects and even potential pro-convulsant effects. The role of THC needs further study to evaluate its role in epilepsy.

Epilepsy Ireland will continue to support the need for further research into cannabis-based treatments and the issue of Medicinal Cannabis will be one of the key themes in our National Conference on September 29th in Dublin.