Mirtazapine Treatment of Anxiety in Children and Adolescents With Pervasive Developmental Disorders

• Pediatric Anxiety Rating Scale (PARS) [ Time Frame: Collected at screen (Visit 1) baseline (Visit 2) and endpoint (Week 10) ] [ Designated as safety issue: No ]
  Assesses severity across common anxiety disorders in children including generalized anxiety, social anxiety, separation anxiety and transition-associated anxiety.
• Clinical Global Impressions (CGI) [ Time Frame: Screen (Visit 1) Baseline (Visit 2) and Endpoint (Week 10) ] [ Designated as safety issue: No ]
  The CGI is designed to take into account all factors to arrive at an assessment of severity and response to treatment.

This study will determine the effectiveness of mirtazapine in reducing anxiety in children with autistic disorder, Asperger's disorder and Pervasive Developmental Disorder.

One of the areas receiving very little attention in Pervasive Developmental Disorders (PDDs) is that of anxiety. Anxiety is common in PDD, but has not yet been fully characterized. The primary objective of this study is to conduct a preliminary placebo-controlled trial of mirtazapine for the treatment of anxiety associated with PDDs. We hypothesize that mirtazapine will be safe and well tolerated.

• Drug: Placebo
  Subjects randomized to placebo will receive placebo for duration of the study
  Other Name: Sugar pill
• Drug: Mirtazapine
  Subjects will receive 7.5 mg daily at the start of the trial. The dose will be increased by 7.5 mg weekly for subject weighing less than 5 50kg and up to 15 mg weekly for subjects weighing more than 50kg depending upon efficacy and tolerability.
  Other Name: Geodon
• Drug: Mirtazapine
  Subjects will receive 7.5 mg of mirtazapine daily initially. The dose will be increased by 7.5 mg for subjects weighing less than 50kg and up to 15 mg per week for subjects weighing more than 50kg. depending upon efficacy and tolerability.
  Other Name: Geodon

• Experimental: Mirtazapine
  The starting dose for subjects is 7.5 mg daily. The maximum daily dose will be 45 mg.
  Interventions:

  • Drug: Mirtazapine
  • Drug: Mirtazapine
• Placebo Comparator: Placebo
  Subjects randomized to placebo arm will receive capsules identical in size and appearance to those subjects receiving study drug. Placebo capsules contain inactive ingredients.
  Intervention: Drug: Placebo

Inclusion Criteria:

• Ages 5-17 years
• Diagnosis of autistic disorder, Asperger's disorder or Pervasive Developmental Disorder Not Otherwise Specified (PDD NOS)
• Clinically significant anxiety as evidenced by a Pediatric Anxiety Rating Scale (PARS) score of 10 or greater
• Abbreviated intelligence quotient (IQ) greater than 50 on the Stanford Binet 5th Ed.

Exclusion Criteria:

• Diagnosis of Rett's disorder or childhood integrative disorder.
• Diagnosis of obsessive-compulsive disorder (OCD), post-traumatic stress disorder, major mood disorder, psychotic disorder, or substance use disorder
• Presence of any past or present medical conditions that would make treatment with mirtazapine unsafe
• Use of other antidepressants or benzodiazepines
• Use of other psychotropic medications which are ineffective, poorly tolerated, or sub-optimal in terms of dose.
• Previous adequate trial of mirtazapine.