Medicinal cannabis reduces seizures in children with Dravet syndrome, clinical study shows
Medicinal cannabis has been found to reduce seizures by half in children with a rare form of drug-resistant epilepsy – bringing hope to a Kiwi family who deal with the condition daily.
The results mark the first scientific clinical evidence of plant-derived cannabinoid therapeutic medication on epilepsy, and mean the drug will come to market, a Kiwi researcher says.
In a double-blind trial, 120 children and young adults with Dravet syndrome and drug-resistant seizures received either cannabidiol oral solution (CBD) or a placebo.
One in 20 of the children on cannabidiol became totally seizure free over the three-month study.
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"We found that convulsive seizures in children on the cannabidiol decreased from 12 to six seizures per month, while those children taking placebo only decreased from 15 to 14 seizures per month," University of Otago, Wellington researcher Associate Professor Lynette Sadleir said.
While this was the first trial of its kind, Sadleir said the results were promising: "It means this will come to market".
The trials were carried out on people through Europe and the US, where researchers measured the change in convulsive-seizures over a 14 week trial period, when compared with a four-week baseline.
The medication used was a 97 per cent pure pharmaceutical grade CBD.
"It's important for people not to generalise too much. This isn't saying people with epilepsy should smoke cannabis," Sadleir said.
There was no requirement to trial it on New Zealand children specifically before it could be made available here.
It was: "fantastic to get another anti-epilepsy medication that is going to help these children," Sadleir said.
Dravet syndrome is a form of severe genetic childhood epilepsy associated with drug-resistant seizures, developmental delay, and a high mortality rate.
There were some adverse side effects including diarrhoea, vomiting, fatigue, fever, sleepiness and abnormal liver function.
"These were so significant that 13 per cent of the children taking cannabidiol withdrew from the study due to side effects."
The short span of the study meant it was unclear what the long term effects of this medication on a child's developing brain might be.
More trials regarding CBD and epilepsy are in the pipeline, with results due to be published shortly.
The CBD used in the trial is manufactured by GW Pharma – the same company which makes Sativex, which isn't suitable for children as it retains the chemical THC which creates the high from cannabis, Sadleir said.
Sadleir, an epilepsy researcher and paediatric neurologist, said previous reports of effects were anecdotal and it was previously unclear if these reflected a true effect for children in general with this type of epilepsy.
The results were published this week in a paper in the New England Journal of Medicine.
'THE HOPE – IT'S MASSIVE'
Kapiti Coast teen Quinne Ayson, 15, had her first seizure when she was 11 months old.
"It's been a rollercoaster ever since," mum Nicola Ayson said.
"Dravet's is one of those conditions where you enjoy the good times and just hold your breath."
Quinne is on four medications and a ketogenic diet, and the family walk a fine balance between managing seizures and managing side effects from the drugs.
Seizures usually strike in clusters. It's not uncommon for Quinne to have three or four "quite hard seizures" during the night.
Due to fatigue, Quinne can manage three hours of school each day, during a good week.
"Some days she doesn't get there – many days she doesn't get there. When she has a good week, we can live more of a normal life.
"We get huge pleasure out of seeing her do something completely normal," Nicola said.
The family have been tempted to try Quinne on cannabis before – medicinal or otherwise – but Nicola wanted it be under the guidance of medical professionals and through legal means.
She was keen to consider this particular CBD for her daughter but admitted that, after 15 years of Quinne's seizures, she had a degree of cynicism about each new drug.
"This is the life we live, and maybe you don't have huge hope another drug will give us this miraculous result – but she could make huge cognitive gains. The hope – it's massive."