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

NCT05494398 | Enrolling By Invitation Phase 2 DMC FDA Drug

• 2 other identifiers: IRB-64292K99HD101702
• Study Type: interventional
• Target: 144
• Locations: 1 country
• Sites: 1

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.

Conditions

Autism Spectrum Disorder

Keywords

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

Outcome Measures

Primary Outcomes (2)

• 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)

  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)

  Screening, Week 8, week 12

Secondary Outcomes (2)

• 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

Study Arms (1)

N-Acetylcysteine

EXPERIMENTAL

Drug: N-acetylcysteine

Interventions

N-acetylcysteine DRUG

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

N-Acetylcysteine

Eligibility Criteria

• Age: 3 Years - 13 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Child (0-17)

You may qualify if:

• 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.

You may not qualify if:

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

Sponsors & Collaborators

• Stanford University: lead
• Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD): collaborator

Study Sites (1)

Stanford University School of Medicine

Stanford, California, 94305, United States

Location

MeSH Terms

Conditions

Autism Spectrum Disorder

Interventions

Acetylcysteine

Condition Hierarchy (Ancestors)

Child Development Disorders, Pervasive; Neurodevelopmental Disorders; Mental Disorders

Intervention Hierarchy (Ancestors)

Cysteine; Amino Acids, Sulfur; Sulfur Compounds; Organic Chemicals; Amino Acids; Amino Acids, Peptides, and Proteins

Study Officials

• John Hegarty, PhD

  Stanford University

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: phase 2
• Allocation: NA
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: SINGLE GROUP
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Instructor

Study Record Dates

• First Submitted: August 8, 2022
• First Posted: August 10, 2022
• Study Start: March 12, 2024
• Primary Completion (Estimated): July 31, 2028
• Study Completion (Estimated): January 31, 2029
• Last Updated: January 20, 2026

Record last verified: 2026-01

Data Sharing

• IPD Sharing: Will share
• Time Frame: The data will be submitted on January 15th and July 15th each year.
• Access Criteria: Researchers with access to the National Database for Autism Research (NDAR) will be able to obtain the submitted data

Locations

US (1)