A Feasibility Study of N-acetylcysteine for Self-injurious Behavior in Children With Autism Spectrum Disorder (NAC)

Emory University

Status and phase: Completed; Phase 2

Conditions: Autism Spectrum Disorder

Treatments: Drug: N-acetylcysteine; Drug: Placebo

Study type: Interventional

Funder types: Other

Identifiers

NCT03008889

IRB00088115

Details and patient eligibility

About

The purpose of this study is to demonstrate the feasibility of a 9-week, randomized trial of N-acetylcysteine (NAC) compared to placebo in 14 children (age 5 to 12 years) with Autism Spectrum Disorder (ASD) and a moderate level of repetitive self-injurious behavior (SIB). Additional aims are to evaluate the positive predictive value of a screening method to classify children with automatically maintained self-injurious behavior; to evaluate the preliminary efficacy of NAC for reducing repetitive SIB in children with ASD; and to evaluate biomarkers and possible mechanisms of action of NAC in children with ASD.

Full description

Self-injurious behavior (SIB) in children with autism spectrum disorder (ASD) can cause physical harm to the child and interfere with the child's ability to make use of educational programs and helpful treatments such as speech therapy. The turmoil caused by self-injurious behaviors in children with ASD invariably interferes with daily routines because family life often stops during these episodes and family members worry about setting off SIB between episodes. This project will use the detailed assessment methods developed in the field of behavior therapy to evaluate the potential for N-acetylcysteine (NAC) to treat children with ASD and moderate repetitive SIB. NAC is an over-the-counter dietary supplement that may have beneficial effects on the brain through its well-documented antioxidant effects and/or reduced glutamate signaling. In the proposed study, 14 children with ASD and repetitive SIB between the ages of 5 and 12 will be randomly assigned to gradually increasing doses of NAC or placebo for 9 weeks. The research team, parents and children will be blind to the treatment with NAC or placebo. Participants will come to the research site periodically to complete measures and behavioral assessments.

After the 9 weeks of treatment, children randomized to NAC who showed improvement will be encouraged to continue taking the supplement outside the study. Children who were randomly assigned to the placebo and showed no improvement will be offered open-label treatment with NAC. Children who did not improve while taking NAC or those who improved while on the placebo will be advised on next steps by the study team.

The goal of this feasibility study is establish the acceptability viability of study procedures in this vulnerable population, to learn about the potential benefits and adverse effects of NAC. Demonstrating these feasibility aims and the preliminary efficacy and safety of NAC is a prerequisite for planning a larger, more definitive, study.

Enrollment: 8 patients

Sex: All

Ages: 5 to 12 years old

Volunteers: Accepts Healthy Volunteers

Inclusion criteria

• Confirmed diagnosis of Autism Spectrum Disorder (ASD)
• Confirmed presence of moderate Self Injurious Behavior (SIB)
• Score > 16 on the parent-rated Aberrant Behavior Checklist Irritability subscale (moderate level of disruptive behavior)
• Classified as having automatically maintained SIB (determined during screening by a detailed functional analysis)

Exclusion criteria

• On a stable medication dose for less than 4 weeks
• Planned change in medication during the 9-week trial
• Had one or more seizures in the last 6 months

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Quadruple Blind

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8 participants in 2 patient groups, including a placebo group

Participants taking NAC

Experimental group

Description:

Participants randomized to the active treatment study arm will receive gradually increasing doses of N-acetylcysteine (NAC) given as a dissolving tablet in juice or water. NAC is an over-the-counter oral dietary supplement that will be used a higher than usual doses in this study.

Treatment:

Drug: N-acetylcysteine

Participants taking Placebo

Placebo Comparator group

Description:

Participants randomized to placebo will receive dissolving tablets identical in size and appearance to the active treatment. Placebo capsules contain inactive ingredients.

Treatment:

Drug: Placebo