Summary of Praxis Precision Medicines (PRAX) Fireside Chat - August 07, 2025 Company Overview - **Company**: Praxis Precision Medicines (PRAX) - **Focus**: Development of therapies for epilepsy, specifically the drug rometragene Key Industry Insights - **Market Size**: Approximately 3 million patients with epilepsy, with over 60% unable to tolerate or respond to current treatments, indicating a significant unmet need in the epilepsy market [10][11] - **Drug Efficacy**: The drug has shown promising results in treating refractory epilepsy, with a notable response rate in difficult-to-treat patients [9][12] Core Points Discussed 1. **Phase One Data**: Initial phase one data did not provide clear differentiation for rometragene compared to other therapies, but subsequent data has shown significant promise [3][6] 2. **RADIANT Study**: The RADIANT study involved 61 patients as of July 25, with a target of 75 patients. The study aims to provide data on both generalized and focal epilepsy patients [13][15] 3. **Patient Response**: The drug has demonstrated a high response rate, with 100% of patients responding in earlier studies, although translating this to broader patient populations remains complex [8][9] 4. **Discontinuation Rates**: The discontinuation rate reported was 23%, primarily occurring within the first three weeks of treatment. This is considered acceptable given the severity of the patient population [36][37] 5. **Safety and Efficacy**: The pharmacokinetics (PK) of rometragene in patients were comparable to healthy volunteers, and the drug did not adversely affect safety or discontinuation rates [22][34] 6. **Seizure Reduction**: The total seizure reduction was reported at 56%, with potential for up to 70% reduction by week eight. The drug's efficacy appears to improve over time [66][72] Additional Considerations - **Patient Recruitment**: The study has faced challenges in patient recruitment due to the complexity of screening and the nature of the patient population [80][81] - **Open Label Data**: Concerns regarding the validity of open-label data were addressed, emphasizing that treatment effects are consistent regardless of whether patients are aware of their treatment status [83][89] - **Future Expectations**: The company anticipates that longer treatment durations will lead to improved outcomes, with ongoing studies expected to confirm these trends [68][72] Conclusion Praxis Precision Medicines is positioned in a significant market with a promising drug candidate for epilepsy. The insights from the RADIANT study and ongoing trials suggest a strong potential for rometragene to address unmet needs in the epilepsy treatment landscape. The company is focused on refining its approach to patient recruitment and data collection to ensure robust outcomes in future studies.