Comparison between Atomoxetine and OROS Methylphenidate as an Adjunctive to SSRIs in Attention-deficit/Hyperactivity Disorder Adults with Comorbid Partially Responsive Major Depressive Disorder: A Head-to-head, 12-week, Randomized, Rater-blinded Clinical Trial

Objective: This study aimed to compare the efficacy and safety of atomoxetine (ATX) and OROS methylphenidate (MPH) as adjunctive to selective serotonin reuptake inhibitors (SSRIs) in adults with attention-deficit hyperactivity disorder (ADHD) with comorbid partially responsive major depressive disorder (MDD). Methods: Sixty Korean adults with ADHD and comorbid partially responsive MDD were recruited in a 12-week, randomized, rater-blinded, active-controlled trial and were evenly randomized to ATX or OROS MPH treatment. Results: Depressive symptoms measured using the Hamilton Depression Rating Scale and Clinically Useful Depression Outcome Scale, and ADHD symptoms measured using the Adult ADHD Self-Report Scale, as well as the Clinical Global Impression-Severity, Clinical Global Impression-Improvement, and the Sheehan Disability Scale scores were significantly improved in both groups during the 12 weeks of treatment. The changes in all outcome measures during the 12-week treatment were not significantly different between the two groups (all p > 0.05). No serious adverse events were reported and there were no significant differences in systolic and diastolic blood pressure, pulse rate, weight, or body mass index between the ATX and MPH groups. Conclusion: Our findings suggest that ATX and MPH can be used as adjunctive treatments in adults with ADHD and comorbid partially responsive MDD. The efficacy and tolerability of ATX and MPH in adults with ADHD did not differ significantly. Further studies should be conducted to draw a definitive conclusion.