Safety, tolerability, and pharmacokinetics of remacemide in children

Eleven patients (nine males, two females), 9–14 years of age, received adjunctive therapy with remacemide in an open ascending-dose study at two residential centers in the United Kingdom. Children taking enzyme-inducing drugs were given remacemide twice daily, starting at approximately 4 mg/kg per day and doubling the dose at two weekly intervals to a target dose of approximately 16 mg/kg per day. Children not taking enzyme-inducing drugs (n = 5) received half of these doses. After the dose-escalation phase, remacemide was slowly withdrawn over 2 weeks except in two children who, because of apparent benefit, entered a continuation phase. Remacemide generally was well tolerated in doses up to 13.5 mg/kg per day. Adverse events were similar to those reported in adults, with central nervous system and gastrointestinal events being the most common. One patient died after a suspected seizure, which was unlikely to have been related to remacemide treatment. No adverse effects on neuropsychologic functioning were observed; effects on vital signs and laboratory variables were not clinically significant. The pharmacokinetic profile for remacemide and its desglycinyl metabolite in children is similar to that seen in adult patients. Plasma concentrations of remacemide and the desglycinyl metabolite are reduced in the presence of concomitant antiepileptic drugs with hepatic enzyme-inducing activity.