Cognitive and behavioral effects of multilayer-release methylphenidate in the treatment of children with attention-deficit/hyperactivity disorder.

OBJECTIVE The aim of this study was to compare the pharmacodynamics of a new multilayer-release (MLR) formulation methylphenidate (MPH; Biphentin) with immediate-release (IR) MPH (Ritalin) in a double-blind, cross-over, placebo-controlled study in patients with attention-deficit/hyperactivity disorder (ADHD). METHOD Patients were randomized to equivalent doses of MPH as MLR (once per day), IR (twice per day) or placebo. Each treatment was taken for 1 week prior to repeated behavioral and cognitive laboratory evaluations on a single day in each phase of the crossover. RESULTS Two girls and 15 boys 6.8-15.3 years old (mean age 11.3 +/- 2.2 years) participated. Both MLR and IR MPH significantly reduced the Stop Signal Reaction Time (p = 0.0001, p = 0.0005), the Errors of Omission on the Continuous Performance Task (p = 0.0039, p = 0.0001), the IOWA-Conners Inattention/Overactivity Index (p = 0.0001, p = 0.0001), and increased the Clinical Global Impressions (CGI) Efficacy Index (p = 0.0001, p = 0.0017) and reduced the CGI Global Improvement Index (p = 0.0001, p = 0.0006) compared to placebo. Mild adverse events were experienced by 4, 6, and 3 patients on placebo, IR, and MLR MPH, respectively. CONCLUSIONS MLR MPH given once daily produces equivalent improvements in behavioral and cognitive measures, and has a duration of effect at least as long as that of IR MPH given twice daily.