Targeting the Neurobiology of RRB in Autism Using N-acetylcysteine: Open Label

Targeting the Neurobiology of Restricted and Repetitive Behaviors in Children With Autism Using N-acetylcysteine: an Open Label Extension

Status

Enrolling by invitation

Phases

Phase 2Phase 3

Study type

Interventional

Source

ClinicalTrials.gov

Registry ID

NCT05494398

Enrollment

144

Registered

2022-08-10

Start date

2024-03-12

Completion date

2029-01-31

Last updated

2026-05-15

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Autism Spectrum Disorder

Keywords

Magnetic Resonance Imaging, N-acetylcysteine, Restricted and Repetitive Behaviors, Electroencephalography

Brief summary

The goal of this study is to target the neurobiology of restricted and repetitive behaviors in children with autism spectrum disorder using N-acetylcysteine (NAC), a well-tolerated nutritional supplement that has shown promise for reducing symptom severity in recent small-scale trials. The findings from this research will shed light on the mechanisms of action underlying the clinical benefits of NAC and the effects of NAC on altering restricted and repetitive behavior symptom severity in children with autism spectrum disorder.

Interventions

DRUGN-acetylcysteine

12 week administration of N-Acetylcysteine to target restricted repetitive behavior severity.

Study design

Allocation

Intervention model

SINGLE_GROUP

Primary purpose

TREATMENT

Masking

NONE

Eligibility

Sex/Gender

ALL

Age

3 Years to 13 Years

Healthy volunteers

Inclusion criteria

* participation in an associated single-dose (IRB-54931, NCT04278898) or randomized, controlled trial of NAC (IRB- 68353, NCT05664789). * stable medication regimens (≥ 30 days) with no anticipated changes during the trial.

Exclusion criteria

• the presence of significant medical problems that reduce medical stability.

Design outcomes

Primary

Measure	Time frame	Description
Change in glutamatergic neurometabolites (Glx) measured by proton spectroscopy Magnetic Resonance Imaging (MRI)	Baseline and Week 12 of treatment	—
Change in restricted and repetitive behaviors as measured by Children's Yale Brown Obsessive Compulsive Scale - Autism Spectrum Disorder (CYBOCS-ASD)	Screening, Week 8, week 12	Higher scores on the Children's Yale Brown Obsessive Compulsive Scale - Autism Spectrum Disorder mean higher levels of restricted and repetitive behaviors (Raw Score Total Range: 0-20)

Secondary

Measure	Time frame	Description
Change in Gamma band amplitude and synchronization measured by electroencephalography (EEG)	Baseline, Week 12	—
Change in restricted repetitive behavior subtypes as measured by the Restricted Behavior Scale - Revised (RBS-R)	Baseline, week 8, week 12	Higher scores on the Repetitive Behavior Scale- Revised mean higher levels of repetitive and restricted behaviors. (Raw Score Total Range: 0 - 129)

Countries

United States

Contacts

PRINCIPAL_INVESTIGATORJohn Hegarty, PhD

Stanford University

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: May 16, 2026