Friday, April 17, 2015

Cannabis-based drug to treat epilepsy

Epilepsy Society: The first ever formal placebo controlled clinical trial for the use of cannabis in treating two forms of childhood epilepsy has just begun in the US. Epidiolex, a medicinal liquid form of cannabis developed by GW Pharmaceuticals, is being trialled in Dravet syndrome, a rare, treatment resistant form of epilepsy. The pharmaceutical company also hopes to begin similar clinical trials of the medication soon for children with Lennox-Gestaut syndrome. Children affected by these syndromes can have as many as 100 seizures a day and cognitive disabilities.

Data supporting the use of cannabis in treating Dravet Syndrome and Lennox-Gestaut syndrome has already been released by the American Academy of Neurology, following an open-label study.  Two hundred and 13 people ranging from toddlers to adults, with an average age of 11 years, took part in the 12-week study, designed to determine whether the drug was safe and well tolerated. All participants were given cannabidiol, a component of cannabis that does not include the psychoactive part of the plant that creates a 'high'.

Out of the 137 people who completed the study, the number of seizures decreased by an average of 54 per cent. A total of 12 people stopped taking the drug due to side effects. The side effects that occurred in more than 10 per cent of participants included drowsiness, diarrhoea and loss of appetite.
Study author Orrin Devinsky of New York University Langone Comprehensive Epilepsy Center and a fellow of the American Academy of Neurology, stressed that these were early findings and that larger, more formal, placebo-controlled double-blind trials were now needed to measure the efficacy of the drug.
In the open label study all patients were aware that they were receiving cannabidiol and this can potentially affect responses with caregivers or patients being over optimistic or biased about outcomes.
Said Professor Devinsky: 'These results are of great interest, especially for the children and their parents who have been searching for an  answer for these debilitating seizures.'

Professor Helen Cross is the Prince of Wales chair of childhood epilepsy and deputy head of developmental neurosciences at University College of London Institute of Child Health. Speaking at the 5th London-Innsbruck Colloquium on status epilepticus and acute seizures, she stressed the need for accurate data about the long-term safety of medicinal cannabis.

'I am asked by parents on almost a daily basis as to why I cannot give it to children in my care' she told delegates. 'We need data about the safety and efficacy of cannabidiol and its possible benefits in treating the co-morbidities of these epilepsy syndromes such as anxiety and cognitive impairments.'