Original Article An Open Study of Adjunct OROS-Methylphenidate in Children and Adolescents Who Are Atomoxetine Partial Responders: I. Effectiveness

Objective: This study evaluated the effectiveness of adding OROS methylphenidate (MPH) to children who are partial responders to atomoxetine (ATMX) in the treatment of attention-deficit=hyperactivity disorder (ADHD). Methods: This is a two-phase, 7-week, open study in children aged 6–17 years. Phase I initiated ATMX for a minimum of 4 weeks. Phase II entered partial responders to ATMX and added up to 54mg of OROSMPH to their regimen. Subjects were assessed on multiple outcomes, including ADHD, executive functioning, and adverse effects. All analyses were intent to treat, with last observation carried forward. Results: Fifty subjects who were partial responders to ATMX were treated with the combination therapy, with 41 subjects completing the entire protocol. There was a 40 % reduction in their ADHD Rating Scale from the start of phase II through the end of study (from 21.14 9.9 to 12.8 9.7, t 6.5, p< 0.0001). In addition, there was a clinically significant reduction in theClinicalGlobal Index ofADHDseverity frommoderate tomildADHD(start of phase II, 3.7; end of phase II, 2.7, 27%, t 6.5, p< 0.0001), as well as improvements in executive functioning. Conclusion: These results suggest that OROSMPH added to the regimen of partial responders to ATMX improves ADHD and executive functioning, necessitating further controlled trials