Study of Aripiprazole in the Treatment of Children and Adolescents With Autistic Disorder (AD)

• Mean Clinical Global Impressions Improvement Scale (CGI-I) Score [ Time Frame: Week 8 ] [ Designated as safety issue: No ]
  The CGI scale is a clinician-rated global assessment of a patient's improvement over time. Baseline assessment rated a patient's condition on a 7-point scale (1=no symptoms, 7=very severe symptoms). Subsequent assessed improvement relative to baseline symptoms on a 7-point CGI-I item scale (1=very much improved, 7=very much worse).
• Number of Participants With Response at Week 8 [ Time Frame: Week 8 ] [ Designated as safety issue: No ]
  Response defined as a ≥ 25% reduction from baseline to endpoint in the ABC Irritability Subscale score and a CGI-I score of 1 or 2 at endpoint.
• Mean Change (Week 8 - Baseline) in the Children's Yale-Brown Obsessive Compulsive Scale (CY-BOCS; Compulsion Scale Only) [ Time Frame: Week 8 ] [ Designated as safety issue: No ]
  CY-BOCS=10-item assessment of obsessive-compulsive symptoms in patients <18 years. 5 items pertaining to compulsions rate symptoms (time spent, interference with functioning, distress, resistance, control) on a 5-point scale (0=no symptoms/minimum severity, 4=extreme symptoms/maximum severity). A decreased in value indicates improvement.
• Mean Change (Week 8 - Baseline) in the Other ABC Subscale Scores [ Time Frame: Week 8 ] [ Designated as safety issue: No ]
  Mean change (Week 8 - baseline) in the other ABC subscale scores (lethargy/social withdrawal; stereotypic behavior; hyperactivity/ noncompliance; inappropriate speech). A decrease in value indicates improvement.
• Mean Change (Week 8 - Baseline) in CGI-Severity (CGI-S) [ Time Frame: Week 8 ] [ Designated as safety issue: No ]
  A CGI-S assessment (a 7-point scale to evaluate the severity of symptoms) was performed at baseline (1=no symptoms; 7=very severe symptoms). The patient's improvement relative to the symptoms at baseline on were assessed on a 7-point CGI-I (1=very much improved; 7=very much worse). A decrease in value indicates improvement.
• Summary of Safety [ Time Frame: continuously throughout the study ] [ Designated as safety issue: Yes ]
  Deaths, Adverse Events (AEs), Serious AEs (SAEs), Treatment-Emergent AEs and AEs leading to discontinuation
• Change From Baseline in Body Weight [ Time Frame: Week 8 ] [ Designated as safety issue: Yes ]
  Adjusted mean change (Week 8 - baseline) in body weight

This study will compare the effectiveness (how well the drug works) of aripiprazole with placebo (fixed dose) in reducing serious behavioral problems in children and adolescents with a diagnosis of autistic disorder (AD).

• Behavioral Symptoms
• Autistic Disorder

• Drug: Aripiprazole
  Tablets, Oral, once daily, 8 weeks
  Other Name: Abilify
• Drug: Placebo
  Tablets, Oral, once daily, 8 weeks

• Experimental: A1
  5 mg
  Intervention: Drug: Aripiprazole
• Experimental: A2
  10 mg
  Intervention: Drug: Aripiprazole
• Experimental: A3
  15 mg
  Intervention: Drug: Aripiprazole
• Placebo Comparator: B1
  Intervention: Drug: Placebo

Inclusion Criteria:

• Meets current Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision (DSM-IV-TR) diagnostic criteria for AD and demonstrates serious behavioral problems; diagnosis confirmed by Autism, Diagnostic Interview-Revised (ADI-R).
• CGI score > = 4 AND an ABC Irritability/Agitation subscale score > = 18 at screening and baseline (randomization)
• Mental age of at least 18 months
• Male or female 6 to 17 years of age inclusive, at the time of randomization

Exclusion Criteria:

• Patients considered treatment resistant to neuroleptic medication based on lack of therapeutic response to 2 different neuroleptics after treatment of at least 3 weeks each
• Patients previously treated and not responding to aripiprazole treatment
• The patient is currently diagnosed with another disorder on the autism spectrum, including PDD-NOS, Asperger's Disorder, Rett's Disorder, Fragile-X Syndrome or Childhood Disintegrative Disorder
• Current diagnosis of bipolar disorder, psychosis, schizophrenia, or major depression
• A seizure in the past year
• History of severe head trauma or stroke
• Non-pharmacologic therapy (e.g., psychotherapy, behavior modification) should be stable prior to screening and consistent throughout the study