A Long Term Extension Study of E2080 in Lennox-Gastaut Patients

Safety was assessed by monitoring and recording all adverse events (AEs), serious adverse events (SAEs), clinical laboratory tests, blood pressure, pulse rate, physical examination, and 12-lead electrocardiogram (ECG). Treatment-emergent adverse events (TEAEs) were defined as AEs that started on or after the date and time of administration of first dose of test drug, but not later than 30 days after discontinuation from the study, or if the AE was present prior to the administration of the first dose of test drug and increased in National Cancer Institute Common Toxicity Criteria (NCI CTC version 3.0) grade during the study or 30 days after discontinuation from the study. AEs were considered serious if it resulted in; death, was life-threatening, hospitalization/prolonged hospitalization, persistent or significant disability/incapacity, or a congenital anomaly/birth defect.

The sum of the frequencies of tonic seizures and atonic seizures was defined as the "tonic-atonic seizure frequency". The percent change in tonic-atonic seizure frequency was calculated using the tonic-atonic seizure frequency per 28 days of the Observation Period in Study 304 as the baseline and the tonic-atonic seizure frequency at Weeks 12, 24, 32, 40, 52 and Week 52 Last Observation Carried Forward (LOCF) as the post-treatment value. Percentage change in tonic - atonic seizure frequency was calculated as follows: [100 x (post-treatment value - baseline)/ baseline]. The frequency of epileptic seizures was recorded in the seizure diary by the recorder. Seizure frequency was counted based on the classification established by the International League Against Epilepsy (ILAE). The diary recorder monitored the participant and recorded the seizure diary in a consistent manner, and continued these practices throughout the study period.

Percent change in the total seizure frequency (per 28 days) was calculated using the total seizure frequency per 28 days of the Observation Period of Study 304 as the baseline and the total seizure frequency per 28 days at Weeks 12, 24, 32, 40, 52 and Week 52 LOCF as the post-treatment value. Percentage change in total seizure frequency was calculated as follows: [100 x (post-treatment value - baseline)/ baseline].

Percent change in the frequency of seizures other than tonic-atonic seizures (per 28 days) was calculated using the total seizure frequency per 28 days of the Observation Period as the baseline and the total seizure frequency per 28 days of the Weeks, 12, 24, 32, 40, 52 and 52 LOCF as the post-treatment value. Percentage change in total seizure frequency was calculated as follows: [100 x (post-treatment value - baseline)/ baseline]. Seizures analyzed other than tonic-atonic seizures included: Partial seizure frequency, Absence seizure, Atypical absence seizure, Myoclonic seizure, Tonic seizure, Tonic-clonic seizure, Atonic seizure, and Unclassified epileptic seizure. This data was based on the diary data collected for 7 days after each visit. Seizure frequency was counted based on the classification established by the ILAE. The diary recorder monitored the participant and recorded the seizure diary in a consistent manner.

Categorized percent change in Tonic-atonic seizure frequency per 28 Days by visit relative to the baseline (Observation Phase in Study 304) was determined based on the diary data collected for 7 days after each visit. The Efficacy Analysis Set was used.

Number of participants with an increase in Tonic-atonic seizure frequency per 28 Days by visit relative to the baseline (Observation Phase in Study 304) was determined based on the diary data collected for 7 days after each visit. The Efficacy Analysis Set was used.