Stoke Therapeutics (STOK) TD Cowen 46th Annual Health Care Conference summary

Key clinical development updates

• EMPEROR phase III study for Dravet syndrome is enrolling well, with completion of enrollment expected in Q2 and data anticipated by mid-2027.

• Longitudinal open-label extension (OLE) data show robust seizure reduction and improvements in cognition and behavior over up to three years, with potential for five-year data at filing.

• The primary endpoint for phase III is seizure reduction at 26 weeks, with secondary endpoints including continuous seizure reduction at 52 weeks and multiple Vineland-3 domains.

• The study is powered at a 90% confidence level with a p-value of 0.01 for secondary endpoints, and statistical significance has been shown in key Vineland domains.

• Central neuropsychologist raters ensure consistency in Vineland scoring across sites.

Regulatory and labeling strategy

• Labeling will leverage both primary/secondary endpoints and Section 14 clinical studies data, including observed longitudinal benefits.

• Breakthrough designation allows for frequent FDA interactions, focusing on mechanistic understanding and disease modification.

• Anticipated label will cover patients aged two and older, aligning with Breakthrough designation.

• U.S. and European regulatory approaches differ in Vineland endpoint analysis: hierarchical in the U.S., composite in Europe.

Market opportunity and access

• Approximately 35,000–40,000 Dravet patients exist in core geographies, with 6,000 immediately addressable at launch.

• Improved genetic testing and ICD-10 coding are expected to increase identification of eligible patients, especially adults.

• Access strategy aims for broad availability, with pricing to reflect value as a disease-modifying therapy rather than an anti-seizure drug.

• Pricing analogs include SPINRAZA and other genetically targeted therapies, with expected pricing in the $600–$800K range.