A new class of epilepsy drugs based on a marijuana ingredient could be become available in the United States as early as the second half of 2018 pending approval from the Food and Drug Administration.

Epidiolex

GW Pharmaceuticals, the maker of the drug called Epidiolex, announced on Wednesday the promising results of a clinical study of the drug.

A group of 171 individuals were randomly assigned to either receive Epidiolex treatment or placebo. The participants were between 2 and 55 years old with a condition called Lennox-Gastaut syndrome. They were also suffering from seizures existing drugs cannot efficiently control.

The participants on average had tried and discontinued use of six anti-seizure treatments and were experiencing 74 "drop" seizures per month. This particular seizure involves the entire body, head and trunk, and often leads to fall and other injuries.

LGS Patients Taking Epidiolex Sees Significant Reduction Seizures

Results of the study, which was reported in the journal Lancet,  showed that over a period of 14 weeks, 44 percent of the patients taking the drug saw significant reduction in seizures. The rate is significantly higher compared with the 22 percent in the placebo group. More of those who were given the experimental drug also experienced a 50 percent or greater reduction in drop seizures.

"LGS is one of the most difficult types of epilepsy to treat and the majority of patients do not have an adequate response to existing therapies," said Elizabeth Thiele, from Harvard Medical School. "These results show that Epidiolex may provide clinically meaningful benefits for patients with LGS."

Epidiolex is based on pure marijuana-derived cannabidiol or CBD. The cannabis compound has been known for its medical benefits sans making people feeling "stoned."

Adverse Events Linked To Use Of Epidiolex

Adverse events associated with use of the drug include diarrhea, decreased appetite, sleepiness, vomiting, and fever. Once given the go-signal to be marketed in the United States, the drug is intended to be used as a prescription drug to be dispensed by doctors.

"Add-on cannabidiol is efficacious for the treatment of patients with drop seizures associated with Lennox-Gastaut syndrome and is generally well tolerated. The long-term efficacy and safety of cannabidiol is currently being assessed in the open-label extension of this trial," investigators wrote in their report.

GW Pharmaceuticals has not yet disclosed the pricing of the drug, but Justin Gover, GW's chief executive officer, said that the company is already in talks with health insurers about coverage.