The Scottish Medicines Council (SMC) approved Epidyolex (cannabidiol), combined with the anti-epileptic medicine clobazam, as a treatment option for children and adults with Lennox-Gastaut or Dravet Syndrome.
Eligible patients, ages 2 and older, can now access oral Epidyolex, developed by GW Pharmaceuticals, cost-free from the country’s National Health Service (NHS).
“We are pleased that eligible children and adults in Scotland will now be able to access this treatment for free on the NHS, alongside the rest of the U.K.,” the patient group Epilepsy Scotland stated in a release on its website.
The cannabidiol was approved for these patients across Europe in 2019, and first approved in the U.S. (under the name Epidiolex) for with a similar indication in 2018. Epidiolex’s label was expanded to include 1-year-old patients in August, and to treat seizures associated with tuberous sclerosis complex, a rare genetic disease in which benign tumors can cause epilepsy.
The SMC has not approved Epidyolex as a treatment option for other types of epilepsy.
Lennox-Gastaut and Dravet syndrome are two rare forms of severe epilepsy associated with frequent, treatment-resistant seizures, and co-conditions, including learning disability, mobility problems, and developmental delays.
Epidyolex is a non-psychoactive cannabinoid compound called cannabidiol (CBD), derived from the cannabis plant and without the mind-altering effects characteristic of delta (9)-tetrahydrocannabinol (THC).
Its anti-epileptic mechanism of action is thought to be partly due to a two-way interaction with clobazam, which increases the metabolites of both cannabidiol and clobazam, along with uncharacterized addition effects independent of natural cannabinoid receptors in the brain.
Its approval was based on two Phase 3 clinical trials in patients 2 to 55 years old with Lennox-Gastaut syndrome: GWPCARE3 (NCT02224560), and GWPCARE4 (NCT02224690).
In both trials, eligible patients had a history of at least two types of generalized seizures that were inadequately controlled with one or more anti-epileptic medications.
GWPCARE3 compared the safety and efficacy of Epidyolex versus a placebo in 225 patients at sites in the U.S., France, Spain, and the U.K. Patients were randomly assigned to either 20 mg/kg or 10 mg/kg of Epidyolex, or to a placebo, daily for 14 weeks.
Seizure frequency was reduced in patients taking the highest dose of Epidyolex by a median (middle) of 41.9%, and by a median of 37.2% in those on the lower dose, compared with 17.2% in the placebo group, according to results published in the New England Journal of Medicine.
GWPCARE4 was conducted in the U.S., the Netherlands, and Poland. It evaluated the efficacy of Epidyolex as an add-on therapy for seizures in 171 patients who did not respond to other treatments. Patients were randomly assigned to 20 mg/kg of Epidyolex or a placebo daily for 14 weeks.
Its findings, published in the journal The Lancet, showed the treatment reduced seizure frequency by a median of 43.9% compared with 21.8% in the placebo group.
The most common side effects reported were sleepiness, diarrhea, decreased appetite, fever, and vomiting.
“It is clear the SMC have listened to families, charities, and clinicians about the profound impacts of these severe and difficult to treat epilepsy syndromes and the long-standing need for further treatment options,” Epilepsy Scotland said in its release.