A Study to Evaluate the Effect of ACT-709478 in Photosensitive Epilepsy Patients

Exclusion Criteria

• •Lactating women
• •Known hypersensitivity to any of the excipients of the study treatment formulation
• •History or clinical evidence of any disease other than epilepsy and/or existence of any surgical or medical condition, which might interfere with the absorption, distribution, metabolism, or excretion of the study treatment (appendectomy and herniotomy allowed, cholecystectomy not allowed)
• •Relevant history of a suicide attempt or suicidal behavior. Any recent suicidal ideation within the last 6 months (categories 4 or 5), or any suicidal behavior within the last 2 years, except for "Non-Suicidal Self-Injurious Behavior" (item also included in the Suicidal Behavior section), as judged by the investigator using the Columbia-Suicide Severity Rating Scale (C-SSRS) at screening
• •History of status epilepticus during the last 12 months
• •History of non-epileptic seizures that cannot be differentiated from the participant's epileptic seizures
• •History of generalized tonic-clonic seizures triggered by IPS
• •Previous history of repeated fainting, syncope, orthostatic hypotension, or vasovagal reactions in the past 5 years
• •Any circumstances or conditions, which, in the opinion of the investigator, may affect full participation in the study or compliance with the protocol