Clinical Study of Lamotrigine to Treat Newly Diagnosed Typical Absence Seizure in Children and Adolescents

This is a multi-center, uncontrolled, open-label study to evaluate the efficacy and safety of lamotrigine monotherapy on newly diagnosed typical absence seizure in children and adolescents in Japan and South Korea. The study period is composed the baseline, fixed escalation phase, escalation phase, maintenance phase, taper phase, and post study examination. During the fixed escalation phase, the investigational product is administered at 0.3 mg/kg/day for 2 weeks (Week 1 to 2), followed by 0.6 mg/kg/day for 2 weeks (Week 3 to 4). Subjects thereafter visit the clinic once every 1 to 2 weeks during the escalation phase to increase the dose by 0.6 mg/kg/day up to a maximum of 10.2 mg/kg/day or 400 mg/day (whichever was less) until patients are confirmed to be seizure-free by HV tests for clinical signs. After seizure free is confirmed by HV-clinical signs, the dose is increased by one level and HV-EEG (electroencephalography) test (first test) is assessed at the next visit. If seizure free is observed by HV-EEG, the same dose is administered. Thereafter, HV-EEG (second test) is assessed at the next visit and if seizure free is confirmed again, the subjects enter the 12-week maintenance phase. During the maintenance phase, patients visit the clinic once every 4 weeks. The dose can be adjusted as necessary within the range of 1.2 to 10.2 mg/kg/day or 400 mg/day (whichever was less) taking into account the status of seizures and the safety. The investigational product is administered once daily (in the evening). However, if the number of tablets is large, twice-daily administration (in the morning and evening) is also allowed. After the completion of maintenance phase, subjects who have responded to lamotrigine without tolerability issues are eligible to enter the extension phase of the study if clinically indicated.