Randomized, controlled trial of OROS methylphenidate once a day in children with attention-deficit/hyperactivity disorder

Objective. A new once-a-day methylphenidate (MPH) formulation, Concerta (methylphenidate HCl) extended-release tablets (OROS MPH), has been developed. This study was conducted to determine the safety and efficacy of OROS MPH in a multicenter, randomized, clinical trial. Methods. Children with attention-deficit/hyperactivity disorder (ADHD; n=282), all subtypes, ages 6 to 12 years, were randomized to placebo (n=90), immediate-release methylphenidate (IR MPH) 3 times a day (tid; dosed every 4 hours; n=97), or OROS MPH once a day (qd; n=95) in a double-blind, 28-day trial. Outcomes in multiple domains were assessed, and data were analyzed using analysis of variance and Kaplan Meier product limit estimates for time to study cessation. The primary time point for analysis was the last available patient visit using last observation carried forward. Results. Children in the OROS and IR MPH groups showed significantly greater reductions in core ADHD symptoms than did children on placebo. This was true both at the end of week 1 and at the end of treatment on the basis of mean teacher and parent IOWA Conners ratings. IR MPH tid and OROS MPH qd did not differ significantly on any direct comparisons. Forty-eight percent of the placebo group discontinued early compared with 14% and 16% in the IR MPH and OROS MPH groups, respectively. Conclusions. For the treatment of core ADHD symptoms, OROS MPH dosed qd and IR MPH dosed tid were superior to placebo and were not significantly different from each other.