A new, pot-based drug for the treatment of childhood epilepsy is one step closer to hitting the American market after British biotech company GW Pharmaceuticals revealed positive findings from late-stage clinical trials last week.
Epidiolex, a purified cannabinoid that comes in a liquid form containing no tetrahydrocannabinol (THC), has been shown to reduce the number of seizures associated with Lennox-Gastaut (LGS) and Dravet syndromes, both rare and severe forms of early-onset epilepsy. When combined with regular treatment, Epidiolex decreased the number of monthly seizures in young patients by up to 42 percent for those taking 20 mg a day.
Researchers had previously found that cannabidiol, or CBD, can be used as an anticonvulsant in animals, but testing on children has remained somewhat taboo. Parents whose kids suffer from childhood epilepsy have resorted to buying weed on the black market or moving their families to medical marijuana–friendly states.
But earlier this year, GW Pharmaceuticals, which is “focused on discovering, developing and commercializing novel therapeutics” derived from cannabis, announced initial findings from its first Phase 3 trial of Epidiolex that could, at least, alleviate harsh symptoms for kids with LGS or Dravet.
“The data … offers the prospect of an FDA-approved CBD medicine that shows both clinically meaningful seizure reduction and a consistent safety and tolerability profile,” says principal researcher Orrin Devinsky. “I believe Epidiolex has the potential to become an important new option within the field of treatment-resistant epilepsy.”
California researchers also have been experimenting with Epidiolex and released their findings at the beginning of the year. The University of California at San Francisco's Pediatric Epilepsy Center, in particular, has been at the forefront of studying cannabis-based medication for the treatment of childhood epilepsy since 2013. The Benioff Children’s Hospital was the first site to administer Epidiolex to one young patient after obtaining special approval from the FDA’s investigational new drug program.
“Better treatment for children with uncontrolled seizures is desperately needed,” says Maria Roberta Cilio, director of research at UCSF's epilepsy center. “It’s important to get seizure control at any age, but in children, uncontrolled seizures may impact brain and neurocognitive development, which can have an extraordinary effect on quality of life and contribute to progressive cognitive impairment.”
Cilio and her team evaluated 162 children and young adults across 11 independent epilepsy centers in the United States. These patients were between the ages of 1 and 30 years old and all suffered from medication-resistant epilepsy. They were treated with Epidiolex over the course of 12 weeks and experienced a median decrease of 36.5 percent in daily seizures. “This trial is pioneering a new treatment for children with the most severe epilepsies, for whom nothing else works,” Cilio says. “This open-label study found that CBD both reduces the frequency of seizures and has an adequate safety profile in children and young adults.”
The outcomes from UCSF's research highlights CBD's medicinal properties at a time when the Drug Enforcement Agency remains squeamish over legalizing recreational pot. Unlike cannabis containing THC, cannabidiol does not contain psychoactive properties and has been shown to have positive effects on people suffering from various ailments.
“Studies have been conducted in healthy adults who have shown CBD to be well tolerated and safe,” says UCSF's Dr. Joseph Sullivan.
“While we don’t know the full side-effect profile in children, this study will allow us to follow the children closely and determine if the side-effect profile differs from that in adults,” Sullivan says.
Epidiolex is considered a Schedule 1 substance with a high potential for abuse, UCSF says. It is closely monitored and restricted by the FDA. GW Pharmaceuticals supplied the cannabidiol for UCSF’s independent study but had no role in the execution of research or the writing of results.
The children who participated in GW Pharmaceutical’s trial had previously tried 10 other medications to help control their seizures. Most still experienced up to three per day, or 90 per month. Thanks to the positive outcomes, 99 percent of the patients have decided to continue participating in an extended trial of Epidiolex, the company says.
LGS, typically surfaces when children are between the ages of 2 and 8 years old and includes multiple types of seizures, such as tonic (stiffening) and atonic (drop). Intellectual development is often, but not always, impaired in patients suffering from LGS. Though causes can be hard to diagnose, LGS is most often associated with chromosomal disorders, cerebral malformations, infections and trauma.
Dravet Syndrome is also a rare genetic disorder that manifests in early childhood with frequent, disabling daily seizures that can number into the hundreds.
Young patients diagnosed with LGS or Davet have behavioral problems, mood swings and personality disorders that can haunt them later into adulthood.
GW Pharmaceuticals plans to submit the drug for approval by the Food and Drug Administration in the first half of 2017.