Open-label Study of Safety and Tolerability of Memantine in Children With Autism

An Open-label Extension Study of the Safety and Tolerability of Memantine in Pediatric Patients With Autism

The purpose of this study is to evaluate the long-term safety and tolerability of memantine in the treatment of autism in pediatric patients.

This is a 48-week multicenter extension study comprised of a 6-week double-blind dose-titration period followed by a 42-week open-label maintenance period. In the Forest autism trials conducted in children ages 6-12, dosing with an extended release formulation of memantine was weight-based. These weight based dose limits were selected to ensure exposure in terms of area under the curve (AUC) was less than the predefined limit of 2100 ng∙h/mL that represented a 10-fold lower exposure than observed at the NOAEL (No observed adverse effect level) of 15 mg/kg/day in juvenile rats. The weight-based dose limits in these studies were as follows: Group A: ≥ 60 kg; max 15 mg/day Group B: 40-59 kg; max 9 mg/day Group C: 20-39 kg; max 6 mg/day Group D: < 20 kg; max 3 mg/day

Once daily oral administration of memantine for 48 weeks: 6-week double-blind dose-titration period followed by a 42-week maintenance period.

Memantine extended release 3- and 6-mg capsules; dose ranging 3 - 18 mg/day; weight based dosing in 4 weight groups; oral administration. Dosing is once daily for 48 weeks.

Inclusion Criteria: Completed lead-in study MEM-MD-57A (NCT00872898) A knowledgeable caregiver capable of providing reliable information about the patient's condition, able to attend all clinic visits with the patient Exclusion Criteria: Patients with a concurrent medical condition that might interfere with the conduct of the study