Core Insights - Zorevunersen shows potential as a disease-modifying treatment for Dravet syndrome, with significant improvements in cognition and behavior observed over two years, contrasting with minimal changes in standard care [1][2][3] - In open-label extension studies, 95% of patients reported improvements in overall clinical status after three years of treatment with zorevunersen [1][2] Company Overview - Biogen Inc. and Stoke Therapeutics are collaborating on the development of zorevunersen, an investigational antisense oligonucleotide aimed at treating Dravet syndrome by increasing functional NaV1.1 protein production [8][9] - Zorevunersen has received orphan drug designation from the FDA and EMA, as well as Breakthrough Therapy Designation for specific mutations in the SCN1A gene [8] Clinical Data - The ongoing open-label extension studies indicate long-term benefits of zorevunersen on seizures, cognition, and behavior, supporting its potential for disease modification [3][4] - Safety data from the studies show that zorevunersen is generally well tolerated, with treatment-emergent adverse events (TEAEs) reported in 30% of patients in Phase 1/2a studies and 53% in open-label extension studies [4] Disease Context - Dravet syndrome is characterized by severe seizures and significant cognitive and behavioral impairments, with over 90% of patients experiencing seizures despite the best available treatments [7] - The estimated prevalence of Dravet syndrome in the U.S. is around 16,000 patients, with no approved disease-modifying therapies currently available [7][17]