RecruitingPhase 1Drug trialRadiprodil in Participants With Hepatic ImpairmentThis Phase 1, open-label study will evaluate the pharmacokinetics (PK), safety, and tolerability of a single oral dose of radiprodil in adults with varying degrees of hepatic impairment compared with healthy participants. Radiprodil is being developed as a potential treatment for GRIN-related neurodevelopmental disorders, tuberous sclerosis complex, and focal cortical dysplasia. Approximately 40 adults aged 18 to 75 years will be enrolled into five cohorts based on liver function (mild, moderate, or severe hepatic impairment) or healthy status. Participants will receive a single 15 mg oral dose of radiprodil and remain in the clinical research unit for intensive PK and safety monitoring through Day 6. The primary objective is to characterize the PK profile of radiprodil in participants with hepatic impairment compared with healthy participants. Safety and tolerability will also be assessed. Results from this study will help determine whether dose adjustments are needed in individuals with impaired liver function.