Dravet syndrome is a severe form of epilepsy (a brain disorder that causes seizures). There are several types of therapies available to help reduce the number of seizures. However, even with treatment using current anti-seizure therapies, the number of seizures may not be reduced enough, and seizures may still happen. 

This study will look at a possible new investigational therapy for Dravet syndrome, called zorevunersen (STK-001). Investigational means that zorevunersen is not approved by the U.S. Food and Drug Adminstration (FDA).  
   
The main purposes of this study are to:
   • evaluate the effect of the study drug on how often children with Dravet syndrome have seizures
   • see if/how the study drug effects the damage caused by Dravet syndrome, including behavioral and developmental delays, and difficulties in language and speech
   • evaluate how long the study drug may reduce the frequency of seizures in children and adolescents with Dravet syndrome (called “durability”)
   • see how safe the study drug is in children and adolescents and how well a child can handle receiving it (called “tolerability”) 
   * This involves checking for side effects, vital signs, overall health, movement and balance, and heart rhythm among other safety checks
   *how the participant’s immune system (body’s defense system) responds to the study drug. 
   • look at how the study drug is taken up and broken down by the body (called “pharmacokinetics” or PK).
   
The EMPEROR Study is split into 2 parts: The baseline period and the study treatment period.