Approved by the US Food and Drug Administration (FDA) this past June 2018, cannabidiol (Epidiolex) stands as the first FDA-approved plant-derived cannabinoid medicine in the United States.

The oral solution is now readily available for patients via prescription in the United States, with an intended use for patients with seizures associated with Lennox-Gastaut syndrome or Dravet syndrome who are aged 2 years or older.

“Cannabidiol is a much-needed new treatment option for patients with Lennox-Gastaut syndrome, a rare and severe form of childhood-onset epilepsy that typically persists into adulthood,” said Christina SanInocencio, executive director of the Lennox-Gastaut Syndrome Foundation, in a recent statement. “Despite the use of multiple epilepsy treatments, the majority of Lennox-Gastaut syndrome patients continue to have life-long, debilitating seizures and our community welcomes the availability of a new, first-in-class treatment option.”

The drug’s approval was determined by the results of 3 randomized, controlled phase 3 clinical trials and an open-label extension study, which indicated that cannabidiol significantly reduced the frequency of drop seizures when treated with other antiepileptic therapies in patients with Lennox-Gastaut syndrome or Dravet syndrome. The studies were published in the New England Journal of Medicine (NEJM) and the Lancet.

In the first phase 3 trial, published in NEJM, patients received either 2 doses of cannabidiol or placebo. The results revealed a 41.9% reduction in drop seizures in patients treated with a 20 mg/kg/day cannabidiol regimen, a 37.2% reduction in those on a 10 mg/kg/day cannabidiol regimen, and a 17.2% reduction in the group given placebo (P = .005 for the 20-mg cannabidiol group vs placebo group, and P = .002 for the 10-mg cannabidiol group vs placebo group).

The group who received 20 mg/kg/day of cannabidiol reported the greatest reduction from baseline in drop-seizure frequency during treatment.

Somnolence; decreased appetite; diarrhea; transaminase elevations; fatigue, malaise, and asthenia; rash; insomnia, sleep disorder and poor quality sleep; and infections included the most common adverse reactions that occurred in patients treated with cannabidiol.

“We are very pleased that cannabidiol—the first medication to be approved by the FDA for patients with Dravet syndrome—is now available,” added Mary Anne Meskis, executive director of the Dravet Syndrome Foundation, in a recent statement. “Our community has long desired a medication specifically approved for the treatment of seizures associated with Dravet syndrome, and the availability of cannabidiol is an important milestone for patients and caregivers whose lives are significantly impacted by this catastrophic, lifelong form of epilepsy.”