A Study to Evaluate the Efficacy and Safety of Risperidone (R064766) in Children and Adolescents With Irritability Associated With Autistic Disorder

• The change from baseline in the Aberrant Behavior Checklist−Japanese Version (ABC-J) Irritability Subscale scores [ Time Frame: Baseline, Week 8 ] [ Designated as safety issue: No ]
  The ABC-J Irritability subscale consists of 15 items. Each item scores range from 0 to 3: 0 = No problem, 1 = Mild aberrant behavior, 2 = Moderate aberrant behavior, and 3 = Severe aberrant behavior. Higher scores represent worse condition.
  
  

• The changes from baseline in the subscale scores of Aberrant Behavior Checklist-Japanese Version (ABC-J) at each evaluation of the double-blind phase [ Time Frame: Baseline, Week 2, Week 4, Week 6 ] [ Designated as safety issue: No ]
  The ABC-J consists of 58 items divided into 5 subscales: Irritability, Lethargy and Social withdrawal, Stereotypic behavior, Hyperactivity/Noncompliance, and Inappropriate speech. Each item scores range from 0 to 3: 0 = No problem, 1 = Mild aberrant behavior, 2 = Moderate aberrant behavior, and 3 = Severe aberrant behavior. Higher scores represent worse condition.
  
  
• The changes from baseline in the subscale scores of Aberrant Behavior Checklist-Japanese Version (ABC-J) at each evaluation of the open-label phase [ Time Frame: Baseline, Week 2, Week 4, Week 8, Week 16, Week 24, Week 32, Week 40, Week 48 ] [ Designated as safety issue: No ]
  The ABC-J consists of 58 items divided into 5 subscales: Irritability, Lethargy and Social withdrawal, Stereotypic behavior, Hyperactivity/Noncompliance, and Inappropriate speech. Each item scores range from 0 to 3: 0 = No problem, 1 = Mild aberrant behavior, 2 = Moderate aberrant behavior, and 3 = Severe aberrant behavior. Higher scores represent worse condition.
  
  
• The changes from baseline in scores of the Clinical Global Impression - Severity (CGI-S) at each evaluation time point of the double-blind phase [ Time Frame: Baseline, Week 1, Week 2, Week 3, Week 4, Week 6, Week 8 ] [ Designated as safety issue: No ]
  The CGI-S rating scale is a 7 point global assessment that measures the clinician's impression of the severity of illness exhibited by a patient. A rating of 1 is equivalent to "Normal, not at all ill" and a rating of 7 is equivalent to "Among the most extremely ill patients". Higher scores indicate worsening.
  
  
• The changes from baseline in scores of the Clinical Global Impression - Severity (CGI-S) at each evaluation time point of the open-label-phase [ Time Frame: Baseline, Week 1, Week 2, Week 3, Week 4, Week 8, Week 16, Week 24, Week 32, Week 40, Week 48 ] [ Designated as safety issue: No ]
  The CGI-S rating scale is a 7 point global assessment that measures the clinician's impression of the severity of illness exhibited by a patient. A rating of 1 is equivalent to "Normal, not at all ill" and a rating of 7 is equivalent to "Among the most extremely ill patients". Higher scores indicate worsening.
  
  
• The changes from baseline in scores of the Children's Global Assessment Scale (C-GAS) at each evaluation time point of the double-blind phase and open-label-phase [ Time Frame: Baseline, Week 4, Week 8 ] [ Designated as safety issue: No ]
  The C-GAS rates the patient's general psychological and social functioning on scores ranging from 1 through 100. Lower scores (range 1-10) mean that the patient needs constant supervision; higher scores (range 91-100) mean that the patient has a superior functioning in all areas.
  
  
• The changes from baseline in scores of the Children's Global Assessment Scale (C-GAS) at each evaluation time point of open-label-phase [ Time Frame: Baseline, Week 4, Week 8, Week 16, Week 24, Week 32, Week 40, Week 48 ] [ Designated as safety issue: No ]
  The C-GAS rates the patient's general psychological and social functioning on scores ranging from 1 through 100. Lower scores (range 1-10) mean that the patient needs constant supervision; higher scores (range 91-100) mean that the patient has a superior functioning in all areas.
  
  
• The Clinical Global Impression−Change (CGI-C) at each evaluation time point of the double-blind phase [ Time Frame: Week 1, Week 2, Week 3, Week 4, Week 6, Week 8 ] [ Designated as safety issue: No ]
  The CGI-C assesses the patient's condition on the basis of the rater's impression, on a 7-point scale ranging from 1 (Very much improved) to 7 (Very much worse).
  
  
• The Clinical Global Impression−Change (CGI-C) at each evaluation time point of the open label-phase [ Time Frame: Week 1, Week 2, Week 3, Week 4, Week 8, Week 16, Week 24, Week 32, Week 40, Week 48 ] [ Designated as safety issue: No ]
  The CGI-C assesses the patient's condition on the basis of the rater's impression, on a 7-point scale ranging from 1 (Very much improved) to 7 (Very much worse).
  
  
• The Parent Satisfaction Questionnaire (PSQ) at each evaluation time point of the double-blind phase [ Time Frame: Week 1, Week 2, Week 3, Week 4, Week 6, Week 8 ] [ Designated as safety issue: No ]
  The PSQ evaluates the caregiver's satisfaction with the study drug.
  
  
• The Parent Satisfaction Questionnaire (PSQ) at each evaluation time point of the open label-phase [ Time Frame: Week 1, Week 2, Week 3, Week 4, Week 8, Week 12, Week 16, Week 20, Week 24, Week 28, Week 32, Week 36, Week 40, Week 44, Week 48 ] [ Designated as safety issue: No ]
  The PSQ evaluates the caregiver's satisfaction with the study drug.
  
  

This is a randomized (the drug is assigned by chance), 8-week, double-blind (neither physician nor patient knows the treatment that the patient receives), placebo-controlled (placebo is an inactive substance that is compared with a drug to test whether the drug has a real effect in a clinical trial), parallel-group (each group of patients will be treated at the same time), flexible-dose, multicenter study. It will be followed by a 48-week, flexible-dose, open-label (all people know the identity of the intervention) extension, to evaluate the efficacy and safety of risperidone in children and adolescents with a diagnosis of autistic disorder (severe form of pervasive developmental disorder) who have associated irritability. The study consists of up to 2-week screening phase, an 8-week double-blind phase, a 48-week open-label phase, and a 1-week follow-up phase.