A Study to Evaluate XEN1101 as Adjunctive Therapy in Primary Generalized Tonic-Clonic Seizures

Exclusion Criteria

• •1. Subject has had status epilepticus within the 12 months prior to Visit 1.
• •2. Subject has history of repetitive seizures within the 12-month period preceding Visit 1 where the individual seizures cannot be counted.
• •3. Subject has a history of non-epileptic psychogenic seizures.
• •4. Subject has a concomitant diagnosis of focal-onset seizures (FOS).
• •5. Subject has presence or history of a developmental and epileptic encephalopathy, including Lennox-Gastaut syndrome.
• •6. Subject has seizures secondary to drug or alcohol use, ongoing infection, neoplasia, demyelinating disease, degenerative neurological disease, metabolic illness, progressive structural lesion, encephalopathy, or progressive central nervous system (CNS) disease.
• •7. Subject has history of neurosurgery for seizures \<1 year prior to Visit 1, or radiosurgery \<2 years prior to Visit 1.
• •8. Subject has schizophrenia and other psychotic disorders (eg, schizophreniform disorder, schizoaffective disorder, psychosis not otherwise specified), bipolar disorder, obsessive-compulsive disorder, or another serious mental health disorder. Subject has uncontrolled unipolar major depression where changes in pharmacotherapy are needed or anticipated during the study.
• •9. Subject has any clinically significant laboratory abnormalities or clinically significant abnormalities on prestudy physical examination, vital signs, or ECG that, in the judgment of the investigator, indicate a medical problem that would preclude study participation, including but not limited to:
• •a. History or presence of long QT syndrome; QTcF \>450 msec at baseline; family history of sudden death of unknown cause.
• •10. Any personal circumstance that, in the opinion of the investigator, prevents adherence to the protocol.
• •The criteria to be eligible for randomization are:
• •1. During the last 56 days of the baseline period that preceded the randomization visit (Visit 2), subject must have had a sufficient documented seizure frequency of PGTCS, including ≥1 PGTCS during each of the first and second 4-week periods preceding randomization.
• •2. Seizure diary was completed a minimum of 80% of all days (ie, ≥45 days) during the last 56 days of the baseline period that preceded randomization as evidence of adequate compliance.
• •3. Subject did not change dose of, stop, or initiate any new ASM(s) during the baseline period and plans on maintaining a stable dose of ASM(s) during the DBP.