A Phase 2 interventional study of N-acetyl cysteine and Placebo in Cornelia de Lange Syndrome, sponsored by Johns Hopkins University. Not yet recruiting at 1 site in United States. Open to participants aged 13 Years to 35 Years. Per ClinicalTrials.gov, last updated 2026-08-14.
Sponsored by Johns Hopkins University · Phase 2, Interventional, and Treatment
This research project is a randomized cross-over pilot trial which aims to test the efficacy of N-acetylcysteine (NAC) for the treatment of Repetitive Behaviors (RB) and self-injurious behavior (SIB) in patients with Cornelia de Lange Syndrome (CdLs).
NAC is a known anti-oxidative stress and neuroprotective agent, which has been shown to decrease the occurrence of SIB such as skin picking. NAC has also shown partial response in trials for compulsive behaviors in Obsessive Compulsive Disorder (OCD) and related disorders in autism.
Cornelia de Lange syndrome (CdLS) is a genetic disorder with autistic features, including RBs and SIB. In this randomized clinical trial, participants with CdLS will be blindly assigned one of two possible treatment arms: 1) placebo (8 weeks) and NAC (8 weeks); or 2) NAC (8 weeks) and placebo (8 weeks), with an intermediate 2-week washout period.
Cornelia de Lange syndrome (CdLS) is a genetic condition caused by mutations in cohesin-related genes, mostly notably NIPBL. The CdLS phenotype includes physical features such as typical facies, limb abnormalities, short stature, and hirsutism as well developmental and behavioral manifestations such as intellectual disability, communication deficits, autistic traits and repetitive/self-injurious behaviors (RBs/SIB).
Behavioral challenges such as RBs/SIB pose a significant obstacle to quality of life to individuals with CdLS and families. In CdLS, disruption of developmental systems can impact neuronal and brain development, and impact GABAergic inhibitory interneuron formation, leading to RBs/SIB. Given the potential for dysregulated excitatory glutamatergic output in CdLS, neuronal oxidative stress may play a role in these maladaptive behaviors. NAC replenishes Central Nervous System (CNS) glutathione, a potent antioxidant and may ameliorate RBs/SIB. NAC has been shown to decrease maladaptive behaviors in autism and grooming disorders such as excoriation disorder (skin picking).
An 18-week cross-over trial is proposed to decrease RBs/SIB comprising two 8-week double-blinded active or placebo treatment with a 2-week wash out period in between. A cross-over design will afford for higher efficiency in sample size for similar power. Dosage will be titrated weekly starting at 600 mg daily and then increased by 600 mg every week to a target dose of 1800 mg per day. Participants will be recruited through CdLS Foundation.
Based on a mechanism for regulation glutamate transmission homeostasis in the central nervous system, the use of NAC may be particularly pertinent to individuals with CdLS. It is known that in CdLS genetic networks that impact on limb formation overlap significantly with developmental systems that impact neuronal and brain development, in particular GABAergic inhibitory interneuron formation. Given a dysregulated excitatory glutamatergic mechanism due to interneuron deficits, which can then lead to neuronal oxidative stress and programmed cell death, NAC may act as a key homeostatic regulator to prevent glutamate overactivity and neuronal damage in CdLS.
303 studies on the registry are indexed under Self-Injurious Behavior; 105 are open to participants now.
This study's planned enrollment of 10 is below the median of 70 across 254 interventional studies indexed under Self-Injurious Behavior.
Browse Self-Injurious Behavior studies →Johns Hopkins University is the lead sponsor of 1,815 studies on the registry; 315 are open to participants now.
Of its 208 completed or terminated interventional studies of FDA-regulated products, 144 (69%) have results posted.
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Exclusion Criteria:
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A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
Contraindication
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
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NAC 1800 milligrams (mg), oral solution, every 8 hours for 8 weeks, followed by a 2-week wash-out period, followed by NAC Placebo-matching solution, orally every 8 hours, for 8 weeks. Dosage will be titrated weekly starting at 600 mg daily and then increased by 600 mg every week to a target dose of 1800 mg per day.
Drug: N-acetyl cysteine · Other: Placebo
NAC Placebo-matching solution, orally every 8 hours, for 8 weeks, followed by a 2-week wash-out period, followed by NAC 1800 milligrams (mg), oral solution, every 8 hours for 8 weeks. Dosage will be titrated weekly starting at 600 mg daily and then increased by 600 mg every week to a target dose of 1800 mg per day.
Drug: N-acetyl cysteine · Other: Placebo
Oral solution for N-acetyl cysteine is prepared in syringes and provided to the participants along with instructions on how to administer them.
Also known as: Acetylcysteine, National Drug Code (NDC): 63323-690
NAC Placebo-matching solution is prepared in syringes and provided to the participants along with instructions on how to administer them.
Change in Children's Yale-Brown Obsessive Compulsive Scale Modified for Pervasive Developmental Disorders (CYBOCS-PDD) repetitive behaviors measure score
CYBOCS-PDD scores range from a minimum of 0 to a maximum of 20, higher scores indicate greater symptom severity. Efficacy of the intervention would be assessed by ≥35% reduction in CYBOCS-PDD repetitive behaviors measure score.
Time frame: Baseline, week 2, week 4, week 6, week 8, week 10, week 12, week 14, week 16, week 18
Change in Aberrant Behavior Checklist (ABC) irritability self-injurious behaviors items score
The ABC irritability sub-scale consists of 15 items of which 3 focus on Self-injurious Behaviors (SIB). Each item takes scores ranging from a minimum of 0 to a maximum of 3. The overall score for the SIB items would range from 0 to 9 with higher scores indicating greater symptom severity. Efficacy of the intervention in reducing self-injurious behaviors would be assessed by a ≥35% reduction in ABC irritability SIB items sub-scale score.
Time frame: Baseline, week 2, week 4, week 6, week 8, week 10, week 12, week 14, week 16, week 18
Change in Aberrant Behavior Checklist (ABC) irritability non-injurious behaviors items score
The ABC irritability sub-scale consists of 15 items of which 12 focus on depressed mood and irritable behaviors (non-injurious behaviors). Each item takes a score ranging from a minimum of 0 to a maximum of 3. The overall score for the non-injurious behavior items would range from 0 to 36 with higher scores indicating greater symptom severity. Efficacy of the intervention in reducing depressed mood and irritability would be assessed by a ≥35% score reduction in ABC irritability non-injurious behavior items of sub-scale.
Time frame: Baseline, week 2, week 4, week 6, week 8, week 10, week 12, week 14, week 16, week 18
Change in total score of Parenting Stress Index/Short Form (PSI/SF)
The PSI-SF is a 36-item questionnaire designed to measure stress in the parent-child system and identify those families most in need of follow-up services. The PSI-SF consists of three sub-scales: Parental Distress, Parent-Child Dysfunctional Interaction, and Difficult Child. Each sub-scale consists of 12 items rated from 1 (strongly disagree) to 5 (strongly agree). Sub-scale scores therefore range from 12 to 60, whereas the total score ranges from 36 to 180. High scores on the PSI-SF total score indicate greater levels of stress.
Time frame: Baseline, week 8, week 10, week 18
Change in Burden Scale for Family Caregivers score
Burden Scale for Family Caregivers, for assessing subjective burden in informal caregivers. It consists of 10 items, each ranging from 0 to 3, with total score ranging from 0 to 30. High scores indicate greater levels of burden in caregiver.
Time frame: Baseline, week 8, week 10, week 18
Change in Sensory Profile score
Sensory profile measure identifies sub-types of individuals based on sensory processing patterns and categorize it as one of the following five profiles: 1- Balanced; 2- Interested; 3- Intense; 4- Mellow until ... ; and 5- Vigilant.
Time frame: Baseline, week 8, week 10, week 18
Change in Childhood Autism Rating Scale (CARS2) score
The Childhood Autism Rating Scale-Second Edition (CARS2) is a 15-item rating scale used to identify children with autism and distinguishing them from those with developmental disabilities. The 15 items can take 4 scores where 1 stands for normal for child's age, 2 for mildly abnormal, 3 for moderately abnormal and 4 for severely abnormal. Scores range form 15 to 60 with 30 being the cutoff rate for a diagnosis of mild autism. Scores 30-37 indicate mild to moderate autism, while scores between 38 and 60 are characterized as severe autism.
Time frame: Baseline, week 8, week 10, week 18
Change in Vineland adaptive Behavior Scale (VABS) score
VABS is a parent interview that provides standard scores (100±15 adjusted for age and gender) for communication, socialization, and daily living.
Time frame: Baseline, week 8, week 10, week 18
Change in Clinical Global Impression - Severity of Illness (CGI-S) score
CGI-S asks the clinician one question: "Considering your total clinical experience with this particular population, how mentally ill is the patient at this time?" which is rated on the following seven-point scale: 1=normal, not at all ill; 2=borderline mentally ill; 3=mildly ill; 4=moderately ill; 5=markedly ill; 6=severely ill; 7=among the most extremely ill patients. This rating is based upon observed and reported symptoms, behavior, and function in the past seven days. Clearly, symptoms and behavior can fluctuate over a week; the score should reflect the average severity level across the seven days.
Time frame: Baseline, week 8, week 10, week 18
Change in Side Effects Survey
A previously used side effect tracker is implemented for measuring patient/caregiver-reported side effects of medication. It consists of 14 side effects of interest which each may take scores ranging from 1 defined as "Not reported" through 5 defined as "Disabling".
Time frame: Baseline, week 2, week 4, week 6, week 8, week 10, week 12, week 14, week 16, week 18
Plan to share: No
Start is estimated for Nov 2026; primary completion for May 2027, 6 months later.
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Studies of the drug tested here: Acetylcysteine