FDA Approves of First Marijuana-Based Drug to Treat Rare Forms of Epilepsy

The FDA recently approved Epidiolex (cannabidiol [CBD]) oral solution for treating seizures associated with 2 rare forms of epilepsy—Lennox-Gastaut syndrome and Dravet syndrome. The approval is for patients 2 years of age or older and marks the first FDA-approved drug that contains a purified drug substance from marijuana.

“This approval serves as a reminder that advancing sound development programs that properly evaluate active ingredients contained in marijuana can lead to important medical therapies. And, the FDA is committed to this kind of careful scientific research and drug development,” FDA Commissioner Scott Gottlieb, MD, said in a statement. “Controlled clinical trials testing the safety and efficacy of a drug, along with careful review through the FDA’s drug approval process, is the most appropriate way to bring marijuana-derived treatments to patients.”

CBD, a chemical component of the Cannabis sativa plant, does not cause intoxication or euphoria that tetrahydrocannabinol (THC) does. THC is the primary psychoactive component of marijuana, not CBD.

The approval of Epidolex marks the first FDA approval of a drug for the treatment of patients with Dravet syndrome. Dravet syndrome is a rare genetic condition that appears with frequent fever-related seizures (febrile seizures) during the first year of life. Over time, additional types of seizures, such as myoclonic seizures (involuntary muscle spasms) will often occur. Also, there is also a chance that status epilepticus—a potentially life-threatening state of continual seizure activity that requires medical care—may occur with Dravet syndrome.

“The difficult-to-control seizures that patients with Dravet syndrome and Lennox-Gastaut syndrome experience have a profound impact on these patients’ quality of life,” said Billy Dunn, MD, director of the Division of Neurology Products in the FDA’s Center for Drug Evaluation and Research. “In addition to another important treatment option for Lennox-Gastaut patients, this first-ever approval of a drug specifically for Dravet patients will provide a significant and needed improvement in the therapeutic approach to caring for people with this condition.”

The other rare form of epilepsy, Lennox Gastaut syndrome begins in childhood involves multiple types of seizures, starting between ages 3 and 5. The majority of children with this syndrome develop learning problems, intellectual disability, and delayed development of motor skills.

The efficacy of the drug was evaluated in 3 randomized clinical trials involving 516 patients with either Lennox-Gastaut syndrome or Dravet syndrome. Epidiolex when taken with other medication was found to be effective in decreasing the frequency of seizures.

The most common side effects included sleepiness, sedation and lethargy, elevated liver enzymes, decreased appetite, diarrhea, rash, fatigue, malaise and weakness, insomnia, sleep disorder, and infections.