WASHINGTON -- Cannabidiol oral solution (Epidiolex) won approval for a new indication and can be used to (TSC) age 1 year and older, the FDA announced late Friday.
Epidiolex is a pharmaceutical formulation of a highly purified oral solution form of cannabidiol (CBD), a component of cannabis that does not cause the high associated with tetrahydrocannabinol (THC). In 2018, drugmaker GW Pharmaceuticals won FDA approval for Epidiolex to treat two other rare epilepsies, Dravet syndrome and Lennox-Gastaut syndrome.
"The FDA continues to believe the drug approval process represents the best way to make new medicines, including any drugs derived from cannabis, available to patients in need of appropriate medical therapy such as the treatment of seizures associated with these rare conditions," Douglas Throckmorton, MD, deputy center director for regulatory programs in the FDA's Center for Drug Evaluation and Research, said in a statement.
"This paradigm ensures new therapies are safe, effective, and manufactured to a high quality that provides uniform and reliable dosing for patients," he added.
TSC is a that affects about 1 in 6,000 people, characterized by benign tumors that can occur in the skin, brain, kidneys, and other organs. About 80% to 90% of people with TSC have .
The FDA decision was based on a in which 148 patients with TSC who received purified CBD as adjunctive treatment experienced a significantly greater reduction in seizure frequency from baseline than patients who received placebo. This effect was seen within 8 weeks and remained consistent throughout the 16-week treatment period.
When the trial results were presented at the American Epilepsy Society meeting in December 2019, Daniel Friedman, MD, of NYU Langone in New York City, noted that purified oral CBD may help a range of epilepsy syndromes and seizure types.
"Open-label prospective studies have suggested it may be an effective treatment for other epilepsy syndromes and etiologies," Friedman told 鶹ý. "This suggests that the mechanisms of CBD's anti-seizure activity do not depend on epilepsy etiology and this drug may help other types of more common intractable epilepsies."
The most common side effects in CBD-treated patients in the trial were diarrhea, elevated liver enzymes, decreased appetite, sleepiness, fever, and vomiting. Patients with Dravet syndrome, Lennox-Gastaut syndrome, or TSC who have used the drug also have experienced liver injury, decreased weight, anemia, and increased creatinine, the FDA said.
"As is true for all drugs that currently treat epilepsy, including Epidiolex, the most serious risks may include an increase in suicidal thoughts and behavior, or thoughts of self-harm," the agency pointed out. "Patients, their caregivers, and their families should be advised to monitor for any unusual changes in mood or behavior, such as worsening depression, suicidal thoughts or behavior."
Epidiolex is the only FDA-approved drug with a purified drug substance derived from cannabis. It is the second drug approved for TSC seizures, the first being (Afinitor), approved in 2018.