GW Research’s Epidiolex, which treats two forms of epilepsy, receives FDA’s approval; spurs FDA reminders about unapproved products.
FDA announced on June 25, 2018 the approval of Epidiolex (cannabidiol) [CBD] oral solution, which contains a purified drug substance derived from marijuana, for the treatment of seizures associated with two rare forms of epilepsy, Lennox-Gastaut syndrome and Dravet syndrome, in patients two years of age and older.
The drug, which will be marketed in the United States by Greenwich Biosciences, the US subsidiary of GW Pharmaceuticals plc, is the first FDA approval of a drug for the treatment of patients with Dravet syndrome. FDA granted Priority Review designation for the application and Fast-Track designation for Dravet syndrome. Both Dravet syndrome and Lennox-Gastaut syndrome indications received Orphan Drug designation.
CBD, a chemical component of the Cannabis sativa plant, does not cause intoxication or euphoria, and is a Schedule I substance under the Controlled Substances Act. The company conducted nonclinical and clinical studies to assess the abuse potential of CBD, FDA reported in a press statement.
The drug must be rescheduled from its current Schedule I before it can be made available to patients, the company reported in a press statement. Rescheduling is expected to occur within 90 days and the drug is expected to be available to patients by Fall 2018.
The drug is under review by the European Medicines Agency for the treatment of seizures associated with Lennox-Gastaut syndrome and Dravet syndrome; the company expects a decision in the first quarter of 2019.
Epidiolex’s effectiveness was studied in three randomized, double-blind, placebo-controlled clinical trials involving 516 patients with either Lennox-Gastaut syndrome or Dravet syndrome. Taken along with other medications, the drug was shown to be effective in reducing the frequency of seizures when compared with placebo, FDA reported.
“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,” said FDA Commissioner Scott Gottlieb, 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. Because of the adequate and well-controlled clinical studies that supported this approval, prescribers can have confidence in the drug’s uniform strength and consistent delivery that support appropriate dosing needed for treating patients with these complex and serious epilepsy syndromes.
“We’ll continue to support rigorous scientific research on the potential medical uses of marijuana-derived products and work with product developers who are interested in bringing patients safe and effective, high quality products. But, at the same time, we are prepared to take action when we see the illegal marketing of CBD-containing products with serious, unproven medical claims. Marketing unapproved products, with uncertain dosages and formulations, can keep patients from accessing appropriate, recognized therapies to treat serious and even fatal diseases,” Gottlieb said.
In a separate statement, Gottlieb outlined FDA’s steps in the drug review and approval process and clarified differences between the purified form of the drug cannabidiol and unapproved uses of medical marijuana.
Dravet syndrome is a rare genetic condition that appears during the first year of life with frequent fever-related seizures. Other types of seizures can arise including myoclonic seizures and status epilepticus. Children with Dravet syndrome typically experience poor development of language and motor skills, hyperactivity, and difficulty relating to others.
Lennox-Gastaut syndrome begins in childhood and is characterized by multiple types of seizures including tonic seizures, which cause the muscles to contract uncontrollably. Children with the syndrome develop learning problems, intellectual disability, and have delayed development of motor skills.
Sources: FDA and GW Pharmaceuticals