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Study on Epidyolex use in treatment resistant epilepsy reports positive findings.

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A two year open-label study from the USA on the use of Epidyolex in treatment resistant epilepsy has reported positive findings. 

An open-label study is one where both the researchers and the patients in the study are aware of the drug or treatment being given. There is no placebo control that is a key feature of "blinded" clinical trials. Instead, the aim is to compare results among different patient sub-groups. The design of open-label studies can mean that the risk of bias is higher.

Epidyolex is a purified CBD medication which currently has strong clinical trial evidence supporting it's use in two rare & severe types of epilepsy - Lennox Gastuat Syndrome & Dravet Syndrome. CBD is an abbreviation of cannabidiol - a non-psychoactive component of the cannabis plant.

This study from the University of Alabama investigated the use of Epidyolex in "general" treatment-resistant epilepsy. The findings were recently featured in leading epilepsy medical journal, Epilepsy & Behaviour.

Over the course of 2 years, the use of Epidyolex was investigated and monitored in 196 patients (80 adults & 89 children). When compared to baseline (the moment treatment with Epidyolex began), the findings reported that:

1) Children with treatment resistant epilepsy

  • 44% of children saw their seizures reduce by at least 50% at month 1 *
  • 41% of children saw their seizures reduce by at least 50% at year 1 *
  • 61% of children saw their seizures reduce by at least 50% at year 2 *
  • Reduction in seizure frequency of 52% at point of follow up at month 1
  • Reduction in seizure frequency of 51% at point of follow up at year 1
  • Reduction in seizure frequency of 75% at point of follow up at year 2

2) Adults with treatment resistant epilepsy

  • 34% of adults saw their seizures reduce by at least 50% at month 1 *
  • 53% of adults saw their seizures reduce by at least 50% at year 1 *
  • 71% of adults saw their seizures reduce by at least 50% at year 2 *
  • Reduction in seizure frequency of 60% at point of follow up at month 1
  • Reduction in seizure frequency of 81% at point of follow up at year 1
  • Reduction in seizure frequency of 85% at point of follow up at year 2

* Note that a 50% reduction in seizures is typically used as a barometer of how well a medication works in treating epilepsy. Generally, if 50% of patients experience a 50% reduction in seizures, that is considered to be a successful outcome.

The study results are very positive over a sustained period of time and suggest that treatment with purified CBD could be a viable treatement option for both adults and children living with treatment resistant epilepsy. However we would note that the study groups are quite small and as an open label study that relied on participants providing seizure data to the research team, the data is not as reliable as that gathered from a double-blind, placebo-controlled study. Nonetheless, this is very encouraging news about the role that CBD may have in treating a wider range of epilepsy types in future.

You can read more on this study by visiting the Epilepsy and Behaviour website. 

Regarding the availability of Epidyolex in Ireland, the medication is currently going through the reimbursement process. The medication is currently indicated for use in Lennox Gastaut Syndrome & Dravet Syndrome. You can read the latest update on this process by reading the associated article by visiting the 'News' section of our website. 

You can also find further details on Medicinal Cannabis & Epilepsy in general by visiting the 'Medicinal Cannabis & Epilepsy' section of our website. 

As we highlight in discussions about any emerging products or medications, please talk to your doctor or epilepsy specialist nurse if you are using or considering using any cannabis-based product.