A Study of Oral N-Acetylcysteine in Children With Autism Spectrum Disorders

Indiana University School of Medicine

Status and phase

Completed

Phase 2

Conditions

Autistic Disorder

Child Development Disorders, Pervasive

Asperger Syndrome

Treatments

Drug: Placebo

Drug: N-acetylcysteine

Study type

Interventional

Funder types

Other

Identifiers

NCT00453180

0611-10

Details and patient eligibility

About

The purpose of this study is to determine whether treatment with oral N-acetylcysteine (NAC) will improve behavior problems often associated with autism spectrum disorders.

Full description

Autism is increasingly being recognized as a common disorder with enormous public health significance. The core symptoms of autism include severe deficits in social relatedness and communication, and interfering repetitive behavior. No medications have been shown to consistently improve any of these symptoms.

The central hypothesis of this study is that NAC will improve behavioral manifestations of autism which may include core or associated symptoms. We plan to test our hypothesis and complete the objectives of this project by pursuing the following specific aims:

Evaluate the efficacy of oral NAC in a 12-week, double-blind, placebo-controlled study involving 32 children and adolescents with autism spectrum disorders.
Evaluate the safety and tolerability of oral NAC in 32 children and adolescents with autism spectrum disorders.

Enrollment

31 patients

Sex

All

Ages

4 to 12 years old

Volunteers

No Healthy Volunteers

Inclusion criteria

Age 4 to 12 years.
Diagnosis of autistic disorder, Asperger's disorder, or PDD NOS.
If taking concomitant psychotropic medications, the medication must be at a constant dose for 60 days with no dose changes planned for the duration of the trial.
Able to swallow capsules.

Exclusion criteria

Presence of any medical condition that significantly increases risk or hampers assessment (e.g., unstable hypertension or cardiac disease, unstable asthma, kidney disease, unstable seizure disorder, pregnancy or any other medical condition as determined by the investigator).
Weight < 15 kg.
Subjects taking concomitant medications or supplements known for their glutamatergic effects (e.g., dextromethorphan, D-cycloserine, amantadine, memantine, lamotrigine, riluzole) or antioxidant properties (high dose vitamin supplements, DMG, TMG, many alternative treatments) within 30 days of the baseline visit with the exception of short term use of dextromethorphan as needed as a cough suppressant. The use of this medicine must be stopped at least 7 days prior to the baseline visit. Regular multivitamins will be allowed.
Subjects taking daily acetaminophen or nonsteroidal anti-inflammatory drugs within 30 days of the baseline visit.
Profound mental retardation as evidenced by a mental age below 18 months.
Subjects taking concomitant medications with the potential for pharmacokinetic or pharmacodynamic drug-drug interactions (e.g., carbamazepine) within 30 days of the baseline visit.
Subjects who are likely to experience significant changes in their ongoing psychosocial or medical treatments for autism over the course of the trial (e.g., initiation of new behavioral therapy, initiation of new medication or alternative treatment [e.g., chelation]). Minor changes in ongoing treatment (e.g., missed therapy sessions due to holiday/vacation; planned break in therapy due to school holidays) will not be considered significant.
History of prior treatment with NAC.
Evidence of hypersensitivity/allergy to NAC.
Presence of certain neurodevelopmental disorders such as Fragile X Syndrome, Tuberous Sclerosis, or other neurological disorders known to be associated with autism or autistic features.
Diagnosis of Rett's disorder, childhood disintegrative disorder, schizophrenia, bipolar disorder, another psychotic disorder, or substance abuse disorder.

Trial design

Primary purpose

Treatment

Allocation

Randomized

Interventional model

Parallel Assignment

Masking

Triple Blind

31 participants in 2 patient groups, including a placebo group

Experimental group

Description:

Target dose for n-acetylcysteine is 60 mg/kg/day. Capsules available in 300 mg and 600 mg strengths.

Treatment:

Drug: N-acetylcysteine

Placebo Comparator group

Description:

Subjects randomized to placebo arm will receive capsules identical in size and appearance to those subjects receiving study drug. Placebo capsules contain inactive ingredients.

Treatment:

Drug: Placebo