Aripiprazole in the Treatment of Irritability in Pediatric Patients (Aged 6–17 Years) with Autistic Disorder: Results from a 52-Week, Open-Label Study

Aim: To report the long-term efficacy of aripiprazole in the treatment of irritability in children and adolescents (ages 6–17 years) with autistic disorder. Methods: This was a 52-week, open-label, flexible-dose (2–15 mg/day) study of aripiprazole for the treatment of children and adolescents with irritability associated with autistic disorder. Eligible subjects were enrolled from two 8-week randomized trials or were enrolled as de novo subjects. "Prior aripiprazole" subjects had received treatment with aripiprazole for 8 weeks before entering this study. Evaluation of efficacy, a secondary objective after evaluation of safety and tolerability in this study, was conducted using the caregiver-rated Aberrant Behavior Checklist–Irritability subscale and the clinician-rated Clinical Global Impression–Improvement score. Results: Three hundred thirty subjects received treatment (de novo, n = 86; prior aripiprazole, n = 174; prior placebo, n = 70) and 199 subjects (60.3%) completed 52 weeks of treatment. At their last study visit, 38.2% of subjects were receiving concomitant central nervous system medications (commonly antidepressants, 13.4%; psychostimulants, 11.5%; antiepileptics, 5.9%). At week 52 (observed cases data set), the mean change from baseline in Aberrant Behavior Checklist Irritability subscale scores was −8.0 in de novo subjects and −6.1 in prior placebo subjects; prior aripiprazole subjects maintained symptom improvement that was achieved with treatment in the prior study. At endpoint, the majority of subjects had a Clinical Global Impressions–Improvement score of 2 (much improved) or 1 (very much improved). Conclusion: Aripiprazole reduced symptoms of irritability associated with autistic disorder in pediatric subjects ages 6–17 years who were studied for up to 1 year.