U.S. FDA approves 1st prescription drug made from marijuana

U.S. health regulators on Monday approved the first prescription drug made from marijuana, a milestone that could spur more research into a drug that remains illegal under federal law in the U.S., despite growing legalization for recreational and medical use.

The U.S. Food and Drug Administration approved the medication, called Epidiolex, to treat two rare forms of epilepsy that begin in childhood. But it's not quite medical marijuana.

The strawberry-flavoured syrup is a purified form of a chemical ingredient found in the cannabis plant but not the one that gets users high. It's not yet clear why the ingredient, called cannabidiol, or CBD, reduces seizures in some people with epilepsy.

FDA officials said the drug reduced seizures when combined with older epilepsy drugs.

Epidiolex is essentially a pharmaceutical-grade version CBD oil, which some parents already use to treat children with epilepsy. CBD is one of more than 100 chemicals found in marijuana. But it doesn't contain THC, the ingredient that gives marijuana its mind-altering effect.

Physicians say it's important to have a consistent, government-regulated version.

"I'm really happy we have a product that will be much cleaner and one that I know what it is," said Dr. Elaine Wirrell, director of the Mayo Clinic's program for childhood epilepsy. "In the artisanal products there's often a huge variation in doses from bottle to bottle depending on where you get it."

Side-effects with the drug include diarrhea, vomiting, fatigue and sleep problems.

Several years ago, Allison Hendershot considered relocating her family to Colorado, one of the first states to legalize marijuana and home to a large network of CBD producers and providers. Her 13-year-old daughter, Molly, has suffered from severe seizures since she was 4 months old. But then Hendershot learned about a trial of Epidiolex at New York University.

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"I preferred this to some of those other options because it's is a commercial product that has gone through rigorous testing," said Hendershot, who lives in Rochester, New York.

Since receiving Epidiolex, Hendershot says her daughter has been able to concentrate more and has had fewer "drop" seizures in which her entire body goes limp and collapses.

Dosages and formulations scrutinized

FDA Commissioner Scott Gottlieb suggested the agency would be scrutinizing CBD products with "uncertain dosages and formulations."

"We are prepared to take action when we see the illegal marketing of CBD-containing products with serious, unproven medical claims," Gottlieb said in a statement.

The FDA previously issued warnings to CBD producers that claimed their products could treat specific diseases, such as cancer or Alzheimer's. Only products that have received formal FDA approval can make such claims, typically requiring clinical trials costing millions.

Most CBD producers sidestep the issue by making only broad claims about general health and well-being.

The FDA approval for Epidiolex is technically limited to patients with Dravet and Lennox-Gastaut syndromes, two rare forms of epilepsy for which there are few treatments. But doctors will have the option to prescribe it for other uses.

Increasing acceptance

The new medication enters an increasingly complicated legal environment for marijuana in the U.S.

Despite increasing acceptance, there is little rigorous research on the benefits and harms of marijuana. Last year a government-commissioned group concluded that the lack of scientific information about marijuana and CBD poses a risk to public health.

Based on the potential for abuse, the U.S. Drug EnforcementAdministration (DEA) categorizes chemicals into five schedules,with Schedule 1 substances like marijuana and heroin considered the most deadly and deemed to have no medicalbenefits.

As a result, Epidiolex's launch remains at the discretion ofthe DEA, which must now evaluate the drug and consider
reclassifying it as a substance that has medical properties, soas to allow GW to begin selling it.

GW Pharma grows its own supply of cannabis in specializedglass houses in the United Kingdom to ensure uniformity in thegenetic composition of the plants, which are then processed intoa liquid solution of CBD.

A GW Pharmaceuticals spokeswoman said the company would not immediately announce a price for the drug, which it expects to launch in the fall. Wall Street analysts have previously predicted it could cost US $25,000 per year, with annual sales eventually reaching $1 billion.