As originally reported in Medscape Neurology News, for the last few years, doctors and researchers have been excited by the new prospect to use an obesity drug, fenfluramine, to treat seizures caused by Dravet Syndrome. Now, a new report published that phase 3 trial results are in with very exciting results: they have found the drug not only reduces the convulsive seizures but the effects have a rapid onset and last over time. The drug additionally does not result in any cardiovascular side effects, which has traditionally been an issue when it comes to fenfluramine. This is quite a feat.

Dravet Syndrome

Dravet Syndrome is a rare genetic disease that causes brain dysfunctioning knowing as epileptic encephalopathy. It is known by its characteristic convulsive seizures.

The seizures which begin their onset in the first year of life and continue for life can damage cognition, resulting in intellectual disability or damage motor control or behavioural disorders. The seizures are frequent, and tend to be resistant to drug treatments. It is important to be diagnosed and treated early in order to prevent more longterm damage. However, many children with DS are already prescribed many different drugs to control the seizures, and even so, they persist.

The Clinical Trials

The drug, fenfluramine had traditionally been used for weight control to treat obesity. However, when it was found that the drug caused an increased risk of valvular heart disease when paired with phentermine, it was taken off the shelf. However, this time, it won’t be taken in this pairing and not in such a high dose. The drug trials used 87 patients who had a mean age of 9.1 who were not currently improving with their treatment options and did not have any cardiovascular issues.

Results

The researchers found that patients who received the drug rather than the placebo had a 54% greater reduction in the monthly frequency of their convulsive seizures, a profound and clinically meaningful finding.  They not only had longer periods between seizures, some patient had only one seizure in the month, while none on the placebo group did. The chief medical officer of Zogenix, Inc and the study investigator of this research, Dr. Bradley S. Galer said this response “is quite unheard of for this [treatment resistent] population.”

Even the other non-seizure related symptoms were reported to be very much improved. It additionally did not make patients overly sleepy, a typical problem with epileptic treatments. They positive results were present regardless of age or gender. The patients did not develop a tolerance, as patients do to most other anticonvulsant medications.

There were some side effects that perhaps could be expected from a repurposed weight loss drug- including weight loss and decreased appetite, as well as fatigue and diarrhea. However, none of the patients discontinued because of this. 

The drug has received priority review to get to the market as quickly as possible. Dr Amy Brooks-Kayal, MD, a relevant specialist sums it up, this news is “definitely exciting.”