• Yale-Brown Obsessive Compulsive Scale (YBOCS): to measure repetitive behaviors [ Time Frame: baseline, 2, 4, 6, 8, 10, 12, 14, 16 weeks ] [ Designated as safety issue: No ]
  
• Aberrant Behavior Checklist (ABC): to measure aggression and irritability [ Time Frame: baseline, 2, 4, 6, 8, 10, 12, 14, 16 weeks ] [ Designated as safety issue: No ]
  
• Clinical Global Impression - Improvement (CGI-I): to measure global functioning [ Time Frame: baseline, 2, 4, 6, 8, 10, 12, 14, 16 weeks ] [ Designated as safety issue: No ]
  

• Repetitive Behavior Scale-Revised. [ Time Frame: baseline, 2, 4, 6, 8, 10, 12, 14, 16 weeks ] [ Designated as safety issue: No ]
  

Autism is a pervasive developmental disorder affecting social, communicative, and compulsive/repetitive behaviors. It is also frequently accompanied by aggression, self-injury, and irritability, making care for these individuals a significant challenge for families or institutional settings. Currently risperidone is the only medication approved by the Food and Drug Administration (FDA) for irritability associated with autism, although not all patients respond to risperidone or are able to tolerate its side effects. As such, additional targeted treatments need to be explored in autism. Neuroimmune disturbance has been demonstrated in patients with autism (Ashwood et al., 2006; DelGuidice, 2003) and the presence of neuroinflammation may play a role in initiating or maintaining CNS dysfunction characteristic of the disorder (Pardo et al, 2005). Therefore, there is considerable interest in using immunomodulatory medications to address core and associated symptoms.

Trichuris suis ova (TSO) are the eggs of intestinal helminthes which induce Th2 cytokine release and nonspecifically downregulate Th1 responsiveness (Summers et al., 2003). Treatment with TSO has been shown to have a beneficial effect in autoimmune inflammatory bowel disease (Summers et al, 2003; Summers et al., 2005a; Summers et al., 2005b) and anecdotal reports from patients with autism have demonstrated that TSO may be effective in reducing repetitive behaviors, aggression, self-injury, and impulsivity.

To date, many medications have been used in individuals with autism and the history of psychopharmacology of autism is notable for the exaggerated benefit of a variety of treatments. To date, most medication studies in the field have been open-label without use of a placebo control and without systematic behavioral assessments. The current practice of prescribing medications to patients with autism without scientifically demonstrated efficacy underscores the necessity for methodologically rigorous studies to be conducted.

We propose a 16 week, open-label trial of TSO to assess the effect on repetitive behaviors, aggression and irritability, and global functioning in adults with autistic disorder. The objectives of the proposed study are to develop an innovative treatment approach to autism by 1) assessing the safety and efficacy of TSO treatment using behavioral and laboratory outcome measures; 2) determining whether this treatment has sufficient promise to warrant consideration of a larger, multi-centered, placebo-controlled clinical trial; 3) conducting secondary analyses to explore the relationship between clinical features, immune mechanisms, and treatment response.