For parents of children with Dravet syndrome, a diagnosis has always meant one thing above everything else: the seizures may never stop.
Dravet syndrome is a rare, severe genetic form of epilepsy caused by a mutation in the SCN1A gene. It begins in infancy. Seizures come in waves — prolonged, sometimes life-threatening, resistant to almost every medication available. Most children with Dravet syndrome have multiple seizures every week. Current treatments can reduce them, but for most families, control remains elusive. And the seizures are only part of it — Dravet also causes cognitive impairment, behavioural difficulties, movement problems, feeding issues. The risk of sudden unexpected death in epilepsy (SUDEP) is real and present.
A generation of children and their families have grown up in the shadow of this diagnosis. For decades, there has been no drug that addresses the root cause of the disease.
Until now.
In a landmark paper published in the New England Journal of Medicine on March 4, 2026, researchers led by UCL and Great Ormond Street Hospital reported the results of clinical trials involving 81 children and adolescents with Dravet syndrome in the UK and US. The drug: zorevunersen — developed by Stoke Therapeutics in collaboration with Biogen.
The results are extraordinary.
Children treated with zorevunersen had up to 91% fewer convulsive seizures. That's not a modest improvement. That's a transformation. Open-label extension studies showed the reduction was sustained across 36 months of continued treatment. In addition to seizure control, the children showed measurable improvements in cognition, behaviour, and quality of life — improvements that persisted and grew over the three-year follow-up period.
For the first time, a treatment is showing signs of modifying the course of the disease — not just managing symptoms.
Here's how it works: humans normally have two copies of the SCN1A gene. In most people with Dravet syndrome, one copy is faulty — it doesn't produce enough of a protein that nerve cells need to function properly. The healthy copy compensates, but not enough. Zorevunersen is an antisense oligonucleotide — a synthetic DNA-like molecule — that binds to a natural brake on the healthy SCN1A gene, releasing it and allowing the gene to produce more protein. It's not fixing the broken gene. It's asking the working one to do more.
The approach is elegant. It targets the underlying biology rather than trying to suppress symptoms downstream.
'These are life-changing results,' said Professor Helen Cross of UCL and Great Ormond Street Hospital, lead author of the study. 'Children who were having multiple seizures a week are now having almost none. We're seeing improvements in how they think, how they behave, their overall quality of life — over years, not just weeks.'
Most of the drug's side effects were mild. A global Phase 3 study — the EMPEROR trial, enrolling approximately 150 patients — is currently underway, with full data readout expected in mid-2027. If it confirms these findings, zorevunersen could move toward regulatory approval in the US and Europe.
One mother in the trial, whose son Tobi was born in 2022, described the results as 'nothing short of a miracle.'
For families who have spent years watching their children seize, who have slept lightly every night in fear, who have learned to administer emergency medication like second nature — that word does not feel like an overstatement.
The seizures may finally stop. 💛