A new Dravet syndrome drug has shown promising results in early clinical trials in children with the rare and hard-to-treat form of epilepsy.
Dravet syndrome is a rare genetic disorder that causes severe epilepsy that is often resistant to treatment and can also lead to speech and developmental delays.
Around 3,000 people in the UK are thought to live with the condition. Existing treatments mainly aim to reduce the number and severity of seizures, but they often have limited effect.
Preliminary trials found the drug, Zorevunersen, appeared safe and well tolerated among the 81 children who took part in the study. Participants were aged between two and 18.
The research was led by University College London and Great Ormond Street Hospital.
Helen Cross is director and professor of childhood epilepsy at the UCL Institute of Child Health and honorary consultant in paediatric neurology at Great Ormond Street Hospital.
She said: “I regularly see patients with hard-to-treat genetic epilepsies, who can have multiple seizures a week.
“Many are unable to do anything independently for themselves; they require around the clock care and are at high risk of sudden expected death in epilepsy.”
Before the study, children experienced an average of 17 seizures per month.
After receiving a 70mg dose of Zorevunersen, seizure frequency fell by around 50 per cent on average, and by about 80 per cent after three doses.
The study also found improvements in quality of life, including motor skills, communication and the ability to cope.
A phase 3 clinical trial will now be conducted to study the treatment over a longer period. This will assess potential long-term risks, identify rare but serious side effects and determine which patients are most likely to benefit.
If the phase 3 trials are successful, she added the treatment “could help children with Dravet syndrome lead much healthier and happier lives.”
Jowinn Chew, head of research at Young Epilepsy, said the preliminary results were a “clinically significant step forward” towards a future treatment that targets the underlying cause of Dravet syndrome rather than only managing symptoms.
Dr Alfredo Gonzalez-Sulser, at the Institute for Neuroscience and Cardiovascular Research at the University of Edinburgh, said the findings were “incredibly exciting” and could suggest new treatment avenues for other hard-to-treat forms of epilepsy.
Gonzalez-Sulser said: “There are now over 800 genetic epilepsies that need therapeutics similar to Zorevunersen.
“This sets a clear path to achieve effective interventions for these severe life-altering diseases for both patients and carers.”
