Study 812P310 is a multicenter, open-label extension study aimed to assess long-term safety and efficacy of SPN-812 in the treatment of ADHD in pediatric subjects who have participated in a previous blinded study of SPN-812.

All subjects who complete a blinded study of SPN-812 will have the option to participate in the OLE study in which all subjects receive SPN-812 (Study Medication, SM). Starting dose, dose range, and dose adjustments are all based on which double blind study the subject completed and, if applicable, the current age of the subject (Table 1). A subject who completed Study 812P202, 812P301 or 812P303, enters this OLE study at age 11 years, and then turns 12 while still in the study, their upper potential dose limit will then be raised from 400 mg to 600 mg and titration may occur at either 100 or 200 mg/week, as specified for the 12-17 year-old age group.

This is a randomized, double-blind, placebo-controlled, multicenter, 2-arm (1:1), parallel group, efficacy, and safety/tolerability fixed-dose study of SPN-812 in preschool-age children (4 to 5 years old) with a DSM-IV-TR diagnosis of ADHD. Approximately 286 subjects will be randomized to either SPN-812 or matching placebo in a 1:1 ratio (143 subjects per arm). Following up to 4 weeks of screening, subjects will be treated with study medication (SM) for 6 weeks, then will either be enrolled in a separate OLE study or followed for an additional 1 week for safety. The total duration of the study is up to 10 weeks.