Pubdate: Tue, 15 Mar 2016
Source: New York Times (NY)
Copyright: 2016 The New York Times Company
Contact: http://www.nytimes.com/ref/membercenter/help/lettertoeditor.html
Website: http://www.nytimes.com/
Details: http://www.mapinc.org/media/298
Author: Andrew Pollack

DRUG BASED ON CANNABIS MEETS GOAL OF BIG TRIAL

An experimental drug derived from marijuana has succeeded in reducing 
epileptic seizures in its first major clinical trial, the product's 
developer announced on Monday, a finding that could lend credence to 
the medical marijuana movement.

The developer, GW Pharmaceuticals, said the drug, Epidiolex, achieved 
the main goal of the trial, reducing convulsive seizures when 
compared with a placebo in patients with Dravet syndrome, a rare form 
of epilepsy. GW shares more than doubled on Monday.

If Epidiolex wins regulatory approval, it would be the first 
prescription drug in the United States that is extracted from 
marijuana. The drug is a liquid containing cannabidiol, a component 
of marijuana that does not make people high.

As many as 30 percent of the nearly 500,000 American children with 
epilepsy are not sufficiently helped by existing drugs, according to 
GW. Parents of some of these children have been flocking to try 
marijuana extracts, prepared by medical marijuana dispensaries.

A number of states, in response to pressure from these parents, have 
passed or considered legislation to make it easier to obtain 
marijuana-based products. And some families have become "marijuana 
refugees," moving to Colorado where it has been easier to obtain a 
particular extract, known as Charlotte's Web, after the girl who 
first used it to control seizures.

Hundreds of other children and young adults have been using Epidiolex 
outside of clinical trials, under programs that allow desperate 
patients to use experimental drugs.

While many parents have reported significant reductions in seizures, 
experts have been cautious about anecdotal reports, saying that such 
treatments needed to be compared with a placebo to make sure they 
work. As such, the results from the GW trial have been closely watched.

"I'm very proud and happy about this study because it is science - we 
did things the way they should be done," the study's lead 
investigator, Dr. Orrin Devinsky of the Comprehensive Epilepsy Center 
at New York University Langone Medical Center, said in an interview. 
"I would strongly advocate that in the United States we need to do 
systematic assessments of medical marijuana."

The study involved 120 patients with an average age of 10 and an 
average frequency of 13 convulsive seizures a month at the start of 
the study, despite taking an average of three other drugs. Half of 
the children were randomly assigned to take the drug and the other 
half the placebo, in addition to the epilepsy medicines they were 
already taking.

The company said that for the patients who received Epidiolex, the 
frequency of convulsive seizures fell by 39 percent during the 
14-week treatment period, compared with a four-week period just 
before the treatment started. For those getting the placebo, the 
reduction was 13 percent. The difference between the two groups was 
statistically significant.

Eight patients getting Epidiolex and one getting the placebo withdrew 
from the trial because of side effects. Major side effects included 
drowsiness, diarrhea, decreased appetite, fatigue, fever, vomiting 
and upper respiratory infection. But GW said that over all, the drug 
was well tolerated.

One caution is that the full details of the study were not released; 
the company said they would be presented at a medical conference.

GW, which is based in London, said Monday that it would meet with the 
Food and Drug Administration to see if Epidiolex could be approved 
based on this single study. It is expecting the results of another 
trial for Dravet syndrome later this year, and the results of two 
trials in another form of epilepsy, Lennox-Gastaut.

There are no drugs approved specifically for Dravet syndrome, which 
typically starts in infancy and affects about 5,000 children in the 
United States, according to the company. It is not yet known if 
Epidiolex can help with the walking problems and intellectual 
disability that can come with Dravet, Dr. Devinsky said.

American depositary receipts of GW closed up about 120 percent on 
Monday. The company, which specializes in cannabis-based 
pharmaceuticals, already sells Sativex to treat spasticity associated 
with multiple sclerosis. It is approved in many countries, though not 
the United States.

While Epidiolex could be the first prescription drug in the United 
States extracted from marijuana, two drugs already on the market, 
dronabinol and nabilone, are synthetic chemicals either similar to or 
identical to delta-9 THC, the component of marijuana that produces the highs.

Those drugs are approved to treat nausea and vomiting caused by 
cancer chemotherapy. Dronabinol is also approved to treat weight and 
appetite loss in patients with AIDS.

GW executives say that an approved pharmaceutical should be favored 
by doctors and patients because the other medical marijuana products 
have not gone through the same rigorous vetting.

A study last year by researchers at Johns Hopkins University and 
elsewhere found that medical marijuana products rarely contained the 
amount of ingredients stated in their labels.

The F.D.A. has been sending warning letters to some companies, many 
of them selling hemp oil, saying that they are illegally marketing 
their products as drugs and that cannabidiol cannot be sold as a 
dietary supplement because it is being studied for use as a drug.

But even if Epidiolex wins approval, some parents might stick with 
other products, either because they do not want to disrupt their 
child's treatment or they prefer a fuller plant extract to the single 
ingredient in Epidiolex.

"My kid's stable. I'm not touching it," said Allison Ray Benavides, 
whose 6-year-old son, Robby, is using Charlotte's Web, to which a 
little of the psychoactive component THC is added.

Robby used to have 15 to 25 seizures a day, even while taking the 
approved drug Depakote, and had to wear a helmet all day to protect 
his head from falls, said Ms. Ray Benavides, a medical social worker 
in San Diego.

Since starting on Charlotte's Web more two years ago, while 
continuing with Depakote, he has had a total of only five seizures.

"I don't need a double-blind placebo-controlled study to know 
something," she said, while nonetheless welcoming the Epidiolex trial results.

Analysts expect Epidiolex to cost $2,500 to $5,000 a month, which 
would be more expensive than some of the medical marijuana products, 
which cost from about $100 to more than $1,000 per month. However, 
Epidiolex might be covered by insurance, unlike the other products.
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MAP posted-by: Jay Bergstrom