Clinical Research Directory

Inclusion Criteria: 1. Children aged 4 to 12 years (after the 4th birthday and before the 13th). 2. Diagnosis of autism spectrum disorder (ASD) according to DSM-5, confirmed by Childhood Autism Rating Scale-Second Edition (CARS-2). 3. Moderate or greater ASD-associated symptoms, defined as a rating of ≥4 ("moderate" or higher) on the Overall Function Clinical Global Impression-Severity (CGI-S). 4. Aberrant Behavior Checklist-Irritability subscale (ABC-I) score ≥18. 5. Social Responsiveness Scale-Second Edition (SRS-2) total T score ≥66. Exclusion Criteria: 1. Body weight \<12.5 kg or ≥57.5 kg. 2. Current or past diagnosis of heart failure, drug addiction, schizophrenia, psychosis, bipolar disorder, post-traumatic stress disorder (PTSD), or major depressive disorder (MDD), or diagnosis of schizophrenia in a first-degree relative. 3. Seizure or change in antiepileptic medications within 4 months prior to randomization. 4. Clinically significant abnormalities on physical examination or laboratory testing, including impairment in cardiac, hepatic, or renal function. 5. Change in pharmacological or behavioral treatment, or change in home or school environment (other than school holidays), within 4 weeks prior to randomization or planned during the study. 6. Cannabinoid treatment within 4 weeks prior to randomization. 7. Predicted poor compliance with study procedures (e.g., blood tests). 8. Concurrent use of opiates or alcohol.