The drug being tested in this study is called soticlestat (TAK-935). The study will assess the safety and tolerability of single oral dose of soticlestat in participants with moderate or mild Hepatic Impairment (HI) compared to healthy participants matched by age (mean ±10 years), sex (±2 per sex), and body mass index (BMI, mean ±10 percent [%]) with normal hepatic function.~The study will enroll approximately 40 participants. Participants will be assigned to following study arms:~Arm 1, Moderate HI: Soticlestat 300 milligram (mg) (Child-Pugh Class B)~Arm 2, Mild HI: Soticlestat 300 mg (Child-Pugh Class A)~Arm 3, Normal hepatic function: Soticlestat 300 mg~All participants will receive single oral dose of study drug. The data will be collected and stored in electronic case report form (eCRF).~This multi-center trial will be conducted in the United States and Hungary. The overall duration of the study is approximately 42 days. Participants will be followed up for 14 days after the last dose of study drug for a follow-up assessment.
The main aim is to check the effect of a single dose of soticlestat in adults with moderate or mild liver failure compared to healthy adults with normal liver function.~Participants will check into the study clinic for 8 days. During the stay, one oral dose of soticlestat will be given and the participant will be monitored. The clinic staff will follow up with the participant about a week after discharge from the clinic.