A marijuana-based drug has effectively treated children who suffer from a rare form of epilepsy known as Dravet syndrome in its first clinical trial, the drug's manufacturer GW Pharmaceuticals announced on Monday.

GW Pharmaceuticals - gwpharm.com

In a major victory for patients and legalization advocates, Epidiolex — a drug derived from a non-psychoactive component of marijuana known as cannabidiol (CBD) — successfully reduced the monthly number of convulsive seizures patients experienced by 39 percent. The placebo in the 120-patient clinical trial showed a 19 percent reduction.

This is the first of four clinical trials designed to demonstrate the medical benefits of cannabis for epilepsy patients that the drug company has planned this year, Reuters reports. Earlier studies of Epidiolex showed promising results, including one open label testing round that found more than 50 percent of 137 participants experienced reduced seizures, but researchers at the time said the findings couldn't be scientifically verified because the test didn't involve a control group or placebo.

What are the next steps?

GW Pharmaceuticals - gwpharm.com

GW Pharmaceuticals will now request a meeting with the FDA to discuss regulatory approval. While there are currently no FDA-approved treatment options for Dravet syndrome, it is unclear whether the drug will be granted approval given the illegal status of marijuana in the U.S.

A spokesperson for the FDA told ATTN: that it was unable to comment on specific drugs or their application status, but said that the federal agency "does not object to the clinical investigation of marijuana for medical use."

"The FDA plays an important role in supporting scientific research into the medical uses of marijuana and its constituents in scientifically valid investigations as part of the agency’s drug review and approval process," press officer Sandy Walsh said. "As a part of this role, the FDA supports those in the medical research community who intend to study marijuana."

GW Pharmaceuticals - gwpharm.com

The news of GW Pharmaceuticals' first clinical success caused its stocks to spike on Monday, more than doubling the company's value, The Wall Street Journal reports. The UK-based pharmaceutical company has also developed a marijuana-based drug, Sativex, designed to treat symptoms of multiple sclerosis, which is available in more than 20 countries but not in the U.S.

That said, Epidiolex is considered more commercially significant because GW Pharmaceuticals has control over the product and plans to roll it out in the U.S, which has a sizeable market for the product.

ATTN: reached out to GW Pharmaceuticals for comment but a representative could not be reached by the time of publication.

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