Clinical Outcomes from an Open-Label Study of Edivoxetine Use in Pediatric Patients with Attention-Deficit/Hyperactivity Disorder

Objective: The purpose of this study was to assess the clinical outcomes from an open label study of edivoxetine, a selective norepinephrine reuptake inhibitor, in pediatric patients with attention-deficit/hyperactivity disorder (ADHD). Methods: This was a multi-cohort open-label study of edivoxetine consisting of a single-dose administration period (Part 1) and an open-label once daily (QD) dose long-term period (Part 2). Adolescents ages 12-17 years and children ages 6-11 years were enrolled in Part 1 and continued to Part 2 where they received 0.05 to 0.3 mg/kg edivoxetine QD for <= 12 months. Safety was assessed by adverse events, vital signs, weight, electrocardiograms, and laboratory tests. In Part 2, Attention-Deficit/Hyperactivity Disorder Rating Scale-Version IV-Parent Reported: Investigator Scored (ADHDRS-IV) and Clinical Global Impressions-ADHD-Severity (CGI-ADHD-S) scores were determined. Results: Fifty-three patients enrolled in Part 1, and 49 continued to Part 2 with a mean exposure duration of 22 weeks. The 31 patients completing Part 2 then entered another long-term open-label study. One serious adverse event of mania was reported; all other treatment-emergent adverse events were mild or moderate in severity. Nausea, decreased appetite, somnolence, increased blood pressure, and upper respiratory tract infection were most frequently reported (three events each). No clinically relevant changes were noted in the laboratory parameters. ADHDRS-IV total score, inattention and hyperactivity/impulsivity subscores, and CGI-ADHD-S scores were statistically significantly improved at endpoint compared with baseline. Conclusions: This study provides preliminary evidence to suggest that edivoxetine at doses <= 0.3 mg/kg/day is safe and may improve ADHD symptoms in pediatric patients. These results require confirmation in larger, double-blind, placebo-controlled trials.