First FDA Approved Drug Derived From Marijuana Used to Treat Two Rare Forms of Epilepsy

The FDA (Food and Drug Administration) approved the first oral cannabidiol solution called Epidiolex in June of 2018. This medicine was approved as a treatment for two forms of severe drug-resistant epilepsy. This is the first time that the federal government has approved a medication derived directly from the cannabis plant. 

LGS (Lennox-Gastaut Syndrome) and DS (Dravet Syndrome) are two rare and severe forms of epilepsy with onset in early childhood. "The syndromes are categorized as developmental and epileptic encephalopathies, in which the epileptic activity is thought to contribute to developmental delay and behavioral abnormalities beyond the pathology of the underlying disease," stated Teresa Buracchio, who is the Clinical Team Leader from the Division of Neurology Products at the FDA. These forms of refractory epilepsy syndromes are resistant to drugs that are typically used for the treatment of seizures. Buracchio further explains that "Both syndromes are associated with higher rates of mortality than in the general epilepsy population, primarily due to status epilepticus and sudden unexpected death in epilepsy patients." 

The FDA conducted three randomized, double-blind, placebo-controlled trials with patients who have LGS and DS. The results from the study performed with 225 patients with LGS showed significant improvement with the use of CBD, "The median number of "drop seizures" (which can cause falls) during a 28-day period fell from 85.5 to 44.9 in the high-dose group (a decrease of 49 percent), from 86.9 to 50 in the low-dose group (43 percent), and from 80.3 to 72.7 in the placebo group (21 percent)." In the study that was performed with 120 patients with DS also showed significant improvement with the use of CBD, "The median number of convulsive seizures over 28 days fell from 12.4 to 5.9 in the CBD group (a drop of 52 percent) and from 14.9 to 14.1 in the placebo group (5 percent)."

Epidiolex contains CBD, which is a cannabinoid found within the marijuana plant. It is known that cannabinoids interact with a multitude of neurotransmitters and neuromodulator systems and have the ability to interact with cellular pathways. By acting as ligands, they are able to modulate a receptor's behavior and their downstream biological pathways. According to GW Pharmaceuticals (the company that created the drug), CBD produces an anticonvulsant effect, it does this by, "...modulating a number of endogenous systems including, but not limited to neuronal inhibition (synaptic and extrasynaptic GABA channels, modulation of intracellular calcium (TRPV, VDAC, GPR55), and possible anti-inflammatory effects."

Both forms of seizures are difficult to control and with the treatment option of CBD for patients diagnosed it can dramatically improve their quality of life. The use of medical marijuana is approved in 30 states and Washington D.C., 25 out of these 30 states specifically recognize epilepsy as a qualifying condition. These states allow treatment of epilepsy with low dose THC or high dose CBD oil and are now making it easier to legally obtain the drug Epidiolex. The creation of this drug and its approval are a huge step in offering patients a safe, controlled, and tested medication. 

Sources: Reason, FDA Briefing Document, GWPharm Mechanism of Action