This will be a randomized, multicenter, parallel group, dose-ranging safety and tolerability study in children with ADHD and persistent serious conduct problems. The target subjects are healthy male or female children aged 6 to 12 years, inclusive, with a diagnosis of ADHD with persistent serious conduct problems. To determine eligibility for the study, subjects will undergo an initial screening visit. Seventy-two subjects will be randomized in the study; assuming a 17% dropout rate, it is anticipated that 60 subjects will complete the study. The study will consist of a Screening Period (within 28 days prior to the first dose administration), a Titration Period of 2 to 5 weeks, a Maintenance Period of 6 weeks, and a Safety Follow-up, which will be performed 30 days after the final study visit. The total subject duration in the study will be 16 to 19 weeks depending on the treatment group assignment. The total study duration is anticipated to be 15.5 months. A total of 72 subjects will be randomized based on weight at baseline, to 1 of 4 treatment groups.
