Cannabis helps prevent seizures in childhood epilepsy

CANNABIDOL (CBD), a type of cannabinoid, has come into focus as a potential therapy for various conditions, including epilepsy.

CBD is looking promising for children with treatment-resistant forms of epilepsy, such as Lennox-Gastaut Syndrome (LGS) and Dravet Syndrome (DS).

Epidiolex, a pharmaceutical liquid formulation of CBD developed by GW Pharmaceuticals, is currently undergoing phase 3 clinical trials in the United States (US), authorized by the US Food and Drug Administration (FDA).

Three studies highlighting the efficacy and safety of CBD were presented at the conference; a fourth discussed its possible interactions with existing anti-epileptic drugs (AEDs).

The largest study presented efficacy and safety data on Epidiolex over a 12-week period.

The 261 participants, mostly children with an average age of 11 years, had severe epilepsy that had not responded adequately to other treatments.

Epidiolex was given in gradually increasing doses, alongside current AED treatment regimes, of which patients were taking an average of three.

Participants and their families/caregivers recorded the number of seizures before taking CBD and during the treatment.

Clinicians also tested hematologic, liver and kidney function as well as AED levels before treatment and then at 4, 8 and 12 weeks during the study.

After three months, the frequency of all seizures was a median of 45 per cent lower in all participants; 47 per cent experienced a 50 per cent or greater reduction in seizures, and nine per cent of patients were seizure-free. Patients with DS experienced a 62 per cent reduction in seizures, and 13 per cent were seizure-free. Those with LGS saw a 71 per cent reduction in atonic seizures.

More than 10 per cent of participants experienced adverse effects, mainly sleepiness, diarrhea and fatigue, causing four per cent of patients to discontinue treatment. Serious adverse events were reported in 34 per cent of patients, of which five per cent were considered treatment-related. These included altered liver enzymes, status epilepticus, diarrhea and others. Lack of efficacy led 12 per cent to withdraw from the study.

Lead author Dr. Orrin Devinsky, of New York University Langone Medical Center’s Comprehensive Epilepsy Center, says: “We are pleased to report these promising data on significant numbers of children. These data reinforce and support the safety and efficacy we have shared in previous studies. Most importantly it is providing hope to the children and their families who have been living with debilitating seizures.”

He notes, however, that as this was an uncontrolled study, further investigations are needed to confirm results. Randomized controlled studies, currently underway, should give a better understanding of the drug’s effectiveness.

In a related study, Dr. Michael Oldham, of the University of Louisville in Kentucky, explored the long-term efficacy of Epidiolex by following 25 people from the previous study, with an average age of nine years, for one year. As before, the patients took CBD with their regular AED regimen.