This release from the NYU Langone Medical Center describes a randomized placebo controlled clinical trial of children and adolescents with Dravet syndome, an extreme form of epilepsy, who often don’t respond to other drugs. The release provides a very good description of the benefits and the side effects that were reported from the trial. It adds cautions and nuance that are missing from many news releases.
But not included were the cost of the new drug (projected to be quite steep) and we think the release could have emphasized more that the children in the trial were already on seizure medications. When the cannabidiol (or a placebo) was added to the maintenance drug it alleviated seizures but also introduced a high degree of side effects.
A CNN story on the study, which we also reviewed, had many of the same strengths as the news release (overall depth and detail on benefits), but it similarly skipped cost information.
Dravet syndrome is a rare form of epilepsy that generally begins in a child’s first year but is a life-long condition, according to the Epilepsy Foundation. Currently, treatments for this condition are marginal and new therapies addressing its symptoms would be welcome. The trial showed reduced seizures in this difficult-to-treat type of epilepsy compared to patients given a placebo. The lead researcher stressed that the study only tested cannabidiol in patients “with especially severe forms who have not responded to numerous medications” and that the drug is not a panacea for other forms of epilepsy.
There was no mention of the cost of the drug but the NYT reported last year that Epidiolex could cost from $2,500 to $5,000 per month. Since the drug isn’t FDA approved, it’s too soon to know whether its cost will be covered by health insurance.
The release describes benefits in clear terms, and provides numbers to add context. It states:
“Specifically, seizure frequency dropped in the CBD-treated group by 39 percent from a median of nearly 12 convulsive seizures per month before the study to about six; three patients’ seizures stopped entirely. In the placebo group, there was a 13 percent reduction in seizures from about 15 monthly seizures to fourteen.”
It also notes that the difference in the degree of seizure reduction between the CBD group and the placebo group was “both statistically significant and clinically consistent.”
The release is clear in mentioning the side effects of the use of this drug in the study: “Side effects – experienced by 93.4 percent of patients in the CBD group and 74.6 percent of those treated with placebo – were generally reported as mild or moderate in severity. The most common side effects in the CBD group were vomiting, fatigue and fever. Eight participants from the CBD group withdrew from the trial due to side effects compared to one participant in the placebo group.”
The study was a randomized, placebo controlled trial which is considered the highest standard of evidence.
While the release didn’t specifically address limitations of this trial, it did recap that this study sought to address some of the limitations present in an earlier open-label study (meaning it wasn’t randomized or compared with a placebo). It states: “The new study confirms results from a December 2015 open-label expanded access program led by Dr. Devinsky that reported reductions in seizure frequency. In that program, both the researchers and patient’s families knew they were receiving CBD, which may have introduced a bias into the results. This new, randomized, controlled clinical study eliminated those concerns as participants and their physicians did not know if they were on CBD or placebo, say the study authors.”
The release did say that larger, future trials will look at whether the benefits of cannabidiol can be achieved at lower, and perhaps less toxic doses.
No evidence of disease mongering here. The release would have been better if it had provided some additional context about Dravet syndrome or on how researchers believe cannabidiol works to reduce seizures.
The release mentions that the trial was funded by GW Pharmaceuticals, the manufacturer of Epidiolex.
In the trial, patients in the experimental group had Epidiolex “added to their existing treatment over a 14-week period,” so it is obvious that other treatments are available. But these standard medications are not alternatives to cannabidiol. Instead, cannabidiol is an add-on treatment, not an alternative to existing drugs. The release could have named those standard medications and noted that other cannabidiol compounds are being studied in people with epilepsy.
The release states that Epidiolex “has not been approved by the U.S. Food and Drug Administration” yet, so readers can assume that it is not yet available to the public. The FDA does, however, consider cannabidiol an investigational product for treating children with epilepsy and has “expanded access provisions” that allow its use. This would have been useful information to include in the release.
The release states that this was “the first large-scale randomized clinical trial for the compound,” adding that the results were both statistically and clinically significant. The release is timed with the publication of the trial results in the New England Journal of Medicine.
Much of what is found in the release was reported in the New York Times on March 14, 2016, but that story noted that full study data was not yet available.
The release doesn’t rely on unjustifiable language. It inserts needed nuance in several places. For example, it states: “Cannabidiol should not be viewed as a panacea for epilepsy, but for patients with especially severe forms who have not responded to numerous medications, these results provide hope that we may soon have another treatment option,” according to the lead researcher.