Study design
The study design consisted of a 30-day screening phase, a DO phase (for new subjects), a 360-day treatment phase, and a follow-up visit. Subjects who successfully completed the laboratory classroom study were rolled over into the current trial within 45 days of their last dose of SDX/d-MPH in the previous study. The rollover subjects bypassed the screening and DO phases and continued into the 360-day treatment phase. These rollover subjects were entered into this trial on the same day as their follow-up visit in the previous study or up to 45 days later. The starting dose for these subjects in the treatment phase was the same as their optimized dose from the previous study.New subjects were defined as those who did not participate in the previous study or entered the trial >45 days after their last dose in the previous study. New subjects underwent screening. For both rollover and new subjects, the dose of SDX/d-MPH could be changed based on their individual response and tolerability to the treatment.During the DO phase (for new subjects only), subjects titrated to their optimized dose based on their individual tolerability and best response to the treatment in the opinion of the investigator. New subjects started treatment with 39.2/7.8 mg SDX/d-MPH daily for 7 days. Dose adjustments, if needed, were performed at approximately weekly intervals. The investigator evaluated the subject's therapeutic response and tolerability to treatment and decided whether the current SDX/d-MPH dose should be increased, decreased, or remain the same for the next week of dosing. The dose at the end of the third week was assigned as the optimized dose consisting of 26.1/5.2, 39.2/7.8, or 52.3/10.4 mg SDX/d-MPH daily. The starting dose during the treatment phase was the optimized SDX/d-MPH dose at the end of the DO phase. During the treatment phase, all subjects continued their optimized dose of SDX/d-MPH daily.