What happened

In response to announcing upbeat results from an important phase 3 trial, shares of Zogenix (ZGNX), a clinical-stage pharmaceuticals company focused on diseases of the central nervous system, surged 16% as of 10:41 a.m. EDT Thursday.

So what

Zogenix shared top-line results from its phase 3 study 1504 today. This trial was designed to test its lead compound ZX008 as a hopeful treatment for children and young adults with Dravet syndrome. Dravet syndrome is a rare form of epilepsy that leads to frequent seizures.

Doctor giving double thumbs up

Image source: Getty Images.

Here are the key findings from the study:

  • ZX008 achieved the study's primary endpoint, which was a statistically significant reduction in convulsive seizures when compared to a placebo. Specifically, 54.7% of patients who took ZX008 showed a greater reduction in mean monthly convulsive seizures than the placebo group. Furthermore, the median reduction in monthly convulsive seizure frequency was 62.7% in the ZX008 group. That was much better than the 1.2% rate observed in patients who received a placebo.  
  • ZX008 also showed statistically significant results in all of the study's secondary endpoints. These endpoints included a reduction in convulsive seizure frequency and duration between seizures.
  • The drug was generally well-tolerated by patients. The number of adverse events observed was consistent with earlier studies.
  • 300 patients remain enrolled in an ongoing safety extension study to monitor potential cardiovascular events.
  • The company affirmed that it is on track to submit ZX008 to regulators in the U.S. and E.U. in the fourth quarter of this year.

Given the news, it is easy to understand why share prices are flying high today.

Now what

Zogenix's CEO Dr. Stephen Farr was enthusiastic about the study's results and offered investors the following commentary:

"Based on these highly compelling top-line results from both of our pivotal studies, we are now focused on submitting applications for regulatory approvals in the U.S. and Europe in the fourth quarter of 2018.  We are excited about ZX008's potential to a have a major impact in the treatment of patients with Dravet syndrome and their families." 

When adding today's clinical news to the fact that ZX008 has already received Breakthrough Therapy designation in the U.S. and is designated as an orphan drug in the U.S. and Europe, the odds look very favorable that the drug will go on to win regulatory approval. If that happens, then the stage is set for a showdown between ZX008 and GW Pharmaceuticals' (GWPH) Dravet syndrome drug Epidiloex in 2019.