CBD shows sustained benefits for severe autism behavioral symptoms

Autism spectrum disorder (ASD) is a heterogeneous neurodevelopmental condition often associated with severe behavioral disturbances and limited pharmacological treatment options. Cannabidiol (CBD) has emerged as a potential therapeutic option; however, evidence on its long-term effectiveness and safety in children with ASD is scarce. To evaluate the long-term effectiveness and safety of purified CBD as addon therapy in children with severe ASD and treatment-resistant behavioral symptoms. We conducted a prospective observational before-and-after study in children and adolescents (3-18 years) with ASD severity levels 2 or 3 and intellectual disability treated with add-on CBD. The primary outcome was change in caregiver-identified symptoms, while secondary outcomes included standardized behavioral scales (Repetitive Behavior Scale-Revised [RBS-R], Vineland Adaptive Behavior Scales-II maladaptive behavior domain, Aberrant Behavior Checklist [ABC], Pediatric Sleep Clinical Global Impressions-Severity, Autism Family Experience Questionnaire, and Parental Stress Scale). Safety and tolerability were assessed through caregiver-reported adverse events. Twenty children were enrolled, of whom 13 completed the long-term follow-up (mean 27.6 ± 1.3 months). Of the caregiver-identified symptoms, improvements observed during the initial short-term study were maintained or further improved during follow-up. Standardized scales showed modest but sustained improvements, particularly in irritability, social withdrawal, and hyperactivity. Mild, transient adverse events, mainly irritability or decreased appetite, did not recur during long-term followup, and concomitant medications were reduced in 40% of patients. Long-term treatment with purified CBD in children with severe ASD was well tolerated and associated with sustained improvement in caregiver-reported outcomes and standardized scales.