6,000 to 8,000 patients live with Dravet syndrome in the US. Roughly three-quarters carry a molecularly confirmed SCN1A mutation, and more than a third remain inadequately controlled on cannabidiol plus fenfluramine, the refractory pool this model sizes precisely.
The Dravet population is small and genetically anchored before it is anything else. A US population-based study at Kaiser Permanente Northern California put incidence at 1 in 15,700 births, with a likely-pathogenic de novo SCN1A mutation confirmed in roughly three-quarters of clinical cases. The Dravet Syndrome Foundation frames the resulting US prevalence at 6,000 to 8,000 patients, a population defined by genetic confirmation rather than by diagnosis code alone.
Treatment share is now fixed across two branded agents. Cannabidiol holds 55 to 60 percent of the Dravet-specific market on a six-year track record, and fenfluramine has taken 25 to 30 percent on a stronger responder rate, though its REMS cardiac-monitoring requirement blocks access for a share of eligible patients. Even with both drugs available, 35 to 40 percent of US patients, an estimated 1,400 to 2,000, remain inadequately controlled, the SCN1A-confirmed, refractory cohort that funds a differentiated launch case rather than a me-too entry.
US Dravet syndrome funnel — from estimated prevalence to the refractory, treatment-eligible pool
| Funnel Stage | Population | Source |
|---|---|---|
| Estimated US Dravet syndrome prevalence | 6,000-8,000 | Dravet Syndrome Foundation |
| SCN1A-confirmed share of clinical cases | ~75% | Wu et al., Pediatrics 2015 (PMID 26438699) |
| On cannabidiol (Epidiolex) | 55-60% of Dravet-specific market | Dravet Syndrome Foundation census 2023 |
| On fenfluramine (Fintepla) | 25-30% of Dravet-specific market | UCB Fintepla REMS programme data 2024 |
| Inadequately controlled on CBD plus fenfluramine | 35-40% (~1,400-2,000 patients) | Dravet Syndrome Foundation census 2023 |
Sources: Wu et al., Incidence of Dravet Syndrome in a US Population, Pediatrics 2015 (PMID 26438699); Dravet Syndrome Foundation census 2023; UCB Fintepla REMS programme data 2024.
What this model answers
Every section answers a named commercial question your team is asking, scoped to your asset.
Delivers
- US prevalence (6,000-8,000, Dravet Syndrome Foundation)
- the ~75% SCN1A-confirmation rate
- the 35-40% inadequately-controlled cohort (1,400-2,000 patients) as the addressable launch target
Delivers
- Cannabidiol's 55-60% share on a six-year loyalty base
- fenfluramine's 25-30% share and REMS access barrier
- the seizure-reduction bar (62% vs 38.9%) a new entrant has to clear
Delivers
- 8-sheet structure (Strategic Context, Inputs, Model, Projections, Sensitivity, References, Market Context, QC)
- formula-driven, zero hardcoded cells
- Pediatrics/Dravet Syndrome Foundation source citation per step
Custom model delivered in 72 hours.
Commission This ModelWhat's inside
- Why SCN1A confirmation, not diagnosis code alone, sets the true addressable pool
- Pressure-tested against the Kaiser Permanente incidence study before the rest of the model is built out
- 6,000-8,000 estimated US Dravet prevalence (Dravet Syndrome Foundation)
- Incidence basis: 1 in 15,700 births (Kaiser Permanente Northern California cohort)
- ~75% of clinical cases with a likely-pathogenic de novo SCN1A mutation
- How genetic confirmation gates access to Dravet-specific therapy
- 55-60% on cannabidiol; 25-30% on fenfluramine
- REMS cardiac-monitoring access barrier for fenfluramine
- 35-40% inadequately controlled (1,400-2,000 patients)
- Medicaid mix and prior-authorization criteria
- Which assumptions move the refractory pool most
- Scenario ranges across SCN1A-confirmed and clinical-only cohorts
- Patient volume by horizon under conservative, base, and aggressive scenarios
- Revenue translation inputs
- The open questions your forecasting team must close before the model is finalised
- Structured for an internal forecast-review session
Included with every brief
How AXLRx builds this model
Prepared by MoatRx analysts.
Every AXLRx patient flow model is built on a five-layer funnel: population, disease burden (E1), diagnosis and specialist capture (E2), treatment and biomarker eligibility (E3), market access (E4), then Year 1-3-5 projections across three scenarios. Delivered as a live Excel workbook, not a static table, with formula-driven sheets and zero hardcoded cells.
US Dravet syndrome sources: Wu et al., Pediatrics 2015 for the SCN1A confirmation and incidence basis, the Dravet Syndrome Foundation for US prevalence and treatment-share census, and UCB's Fintepla REMS programme data.
- US Dravet syndrome prevalence (6,000-8,000) verified against Dravet Syndrome Foundation estimates
- SCN1A confirmation rate (~75% of clinical cases) verified against Wu et al., Pediatrics 2015 (PMID 26438699)
- Cannabidiol and fenfluramine treatment shares (55-60% / 25-30%) and the inadequately-controlled cohort (35-40%, 1,400-2,000 patients) verified against Dravet Syndrome Foundation census 2023
Frequently asked questions
Commission this model
AXLRx delivers rare disease patient flow models built for forecasting and launch teams sizing the US Dravet syndrome opportunity. Custom model in 72 hours.
Specify your indication, market, and cohort definition.
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Research-verified patient flow model in 72 hours with optional analyst readout.