An Open-Label Study of N-Acetyl Cysteine in Children With Autism

N-Acetyl Cysteine (NAC) is a compound that increases the levels of Glutathione, the body's main antioxidant. Glutathione is a compound in the blood that is part of a natural defense system (the antioxidant system). Anti-oxidants protect the body from damage caused by internal toxins called free radicals. It is possible that children with Autism tend to have lower levels of glutathione, an important compound in our bodies that helps combat the effects of toxic free radicals. We hope that by studying the antioxidant system in more detail, we will increase our understanding of the reasons why people develop Autism so that we can design better ways to treat individuals with this condition. This study is meant to test the safety tolerability of N-Acetyl Cysteine and its effectiveness in the treatment of behavioral difficulties in children with autism. It will also examine the possible benefit of this agent in improving the core deficits in autism such as social deficits.

Inclusion criteria

Subjects will be eligible for this study if they participated in the Double-blind, randomized, placebo controlled study of N-Acetyl Cysteine in Autism study at Stanford University and meet all of the following criteria:

• Outpatients between 3.0 and 12.11 years of age inclusive
• Males and females who are physically healthy
• diagnosis of autism based on Diagnostic and Statistical Manual (DSM-IV-TR) criteria, the Autism Diagnostic Interview-Revised, and expert clinical evaluation
• Clinical Global Impression Severity rating of 4
• Care provider who can reliably bring subject to clinic visits, can provide trustworthy ratings, and interacts with subject on a regular basis
• Ability of subject to swallow the compound
• Stable concomitant medications for at least 2 weeks
• No planned changes in psychosocial interventions during the open-label N-Acetyl Cysteine trial

Exclusion criteria

• Diagnostic and Statistical Manual (DSM-IV-TR) diagnosis of schizophrenia, schizoaffective disorder, or psychotic disorder, not otherwise specified
• Active medical problems: unstable seizures, significant physical illness (e.g., serious liver or renal pathology)
• Pregnancy or sexually active females
• Subjects taking antioxidant agents and glutathione prodrugs will be excluded from the study except if they have been off these compounds for at least 4 weeks