Key Takeaway
Dravet syndrome remains one of the most refractory epilepsies in pediatric practice - a disease where clinicians describe their goal not as winning, but as surviving. Three interlocking unmet needs define where current care consistently falls short: insufficient seizure reduction, near-universal cognitive impairment and a high SUDEP risk that no approved therapy can eliminate. A genetic therapy that significantly addresses even two of these gaps would represent a step change, and the enthusiasm from the specialist community is overwhelming.
Based on in-depth interviews with pediatric epileptologists caring for patients at centers of excellence across the United States, REACH’s MarketVue® Dravet Syndrome report synthesizes the clinical realities, treatment algorithm dynamics, and pipeline expectations that shape this market. With a physician-reported average unmet need rating of 6.3 out of 7, Dravet stands at an inflection point: a generation of improved symptomatic therapies has made clear exactly what they cannot do, and the specialist community is looking expectantly at a new category of disease-modifying therapy to do it.
Three Critical Gaps in Current Care
Gap 1: Seizure Burden That Symptomatic Therapies Cannot Resolve
The arrival of fenfluramine (Fintepla) and the renewed focus on stiripentol in recent years has marked genuine progress in Dravet care - and yet surveyed specialists rated current therapy efficacy at just 4.3 on a 7-point scale. The gap between what is approved and what patients actually need becomes stark when the numbers are examined: approximately half of Dravet patients still experience more than one seizure per month despite optimal combination therapy. Some carry a burden measured in daily events.
“The reality is because even though some of the medication trials that have been published now show good efficacy, specifically like fenfluramine, they’re still not seizure-free. Their risk is still high, so it’s better, but if you would have asked me that question a few years ago, I would have said 0 - but now I can only say 2 because we’ve gotten some FDA-approved medications in the last few years.”- Pediatric Epileptologist, U.S.
Gap 2: Cognitive and Developmental Impairment With No Therapeutic Target
Among caregivers, developmental delay and loss of speech rank as the second most troubling dimension of Dravet syndrome after seizures and/or status epilepticus. Among the clinicians REACH interviewed, the consensus was unambiguous: current treatments do not impact cognition.
The relationship between seizure burden and cognitive trajectory is one of the more complex questions in the field. Evidence from fenfluramine’s open-label extension studies suggests that super-responders, patients achieving greater than 75% seizure reduction, showed meaningful cognitive improvements, implying that seizure control and cognitive development are not fully independent. Yet seizure freedom, the threshold at which developmental protection becomes realistic, is achieved by fewer than 5% of patients on current therapies.
“There’s definitely focus on the nonseizure outcomes. The seizures will always be most important, but with these new therapies where the seizures are much less frequent, the other comorbid conditions become much more important. When your kid’s not seizing every day, the fact that they’re not sleeping becomes a much bigger deal - or the fact that their behavior is more difficult to manage is a much bigger deal. If you ask families and caregivers what’s important to them, seizures is still most important, but after that, expressive and receptive communication, behavior, and sleep definitely follow.”- Pediatric Epileptologist, U.S.
Specialists consistently noted that available outcome scales - the Vineland-3, Bayley scales - were not designed for a population with the severity of developmental delay characteristic of Dravet. The Inchstone Project, an ongoing initiative focused on developing scales more sensitive to the incremental changes seen in epileptic encephalopathies, represents a promising direction. What specialists want to see from a disease-modifying therapy, in terms of measurable cognitive endpoints and their clinical significance, is addressed in detail in the full report.
First-in-human efficacy data for Stoke’s ASO STK-001 and Encoded’s AAV therapy ETX101 showed clinically meaningful neurodevelopmental gains on various neurodevelopmental scales providing evidence that early intervention with a genetic therapy may be capable of preventing the neurodevelopmental stagnation that current symptomatic therapies cannot touch.
Gap 3: SUDEP - the Risk That Current Therapies Cannot Eliminate
Of all the ways Dravet syndrome devastates families and clinicians, none is more visceral than SUDEP. Multiple specialists interviewed by REACH described losing one to two patients per year to sudden unexpected death, a rate that puts Dravet at the top of SUDEP statistics across all epilepsy syndromes. Parents rotate shifts sleeping beside their children at night. Families of teenagers and young adults report that managing SUDEP risk reshapes every aspect of their lives.
Current rescue medications can shorten seizure duration and reduce the frequency of status epilepticus episodes but no approved therapy can eliminate the nighttime tonic-clonic seizures that pose the greatest SUDEP risk, and seizure freedom, the only reliable protection, remains out of reach for nearly all patients.
“The fear of SUDEP… is terrifying… A lot of our Dravet kids’ parents rotate sleeping with the child, so that’s not only impactful for the child but on the family dynamics.”- Pediatric Epileptologist, U.S.
The Bottom Line
The ceiling on symptomatic efficacy is not simply a matter of drug potency, it reflects the fundamental nature of the disease: seizures in Dravet are a consequence of haploinsufficiency in SCN1A, and no amount of symptomatic suppression corrects the underlying sodium channel deficit. What physicians want to see from an emerging therapy, particularly a disease-modifying therapy, including specific thresholds for seizure freedom, status epilepticus events, biomarkers and development and cognition and how this compares to what has been achieved by emerging therapies, is detailed in the MarketVue® full report.
Today, fenfluramine is established as a highly effective second-line ASM with long-term cardiac safety confirmed, yet polypharmacy of 3-4 agents remains standard and roughly half of patients still experience frequent seizures. Looking ahead, zorevunersen's Phase 3 EMPEROR study is enrolling globally, with Phase 1/2a and OLE data published in NEJM (March 2026) confirming durable seizure reductions and multi-year cognitive improvements and a primary readout expected mid-2027. Further out, ETX101 first-in-human data (AES Dec 2025) showed 78% median seizure reduction and early neurodevelopmental rescue in the youngest patients - the FDA has granted RMAT designation and a pivotal study initiation is expected in 2026, with one-time AAV administration preferred over ASOs if comparable efficacy is confirmed.
About MarketVue®
MarketVue® is an opportunity assessment report that delivers KOL-informed strategic intelligence for life sciences teams operating in rare and niche disease markets. Each report integrates primary KOL research, market intelligence, and strategic analysis to answer the questions that matter most to development, commercial, and investment teams: where is and what is the size of the opportunity, what does it take to win, and how is the market about to change.