Cannabidiol (CBD) may help reduce problematic behaviors in boys with autism. The corresponding study was published in the Journal of Autism and Developmental Disorders.
Previous research suggests that CBD reduces problematic behaviors in autistic children. A recent systematic review and meta-analysis, for example, found that CBD extracts moderately increase social responsiveness and lead to small but significant reductions in disruptive behavior and anxiety in children and adolescents. Until now, however, no clinical trials have addressed the safety, tolerability, and efficacy of the substance in this population.
To change this, researchers behind the current study conducted a double-blind, placebo-controlled crossover study of plant-derived CBD, Epidolex, to determine safety, tolerability, and behavioral effects in boys with autism. Participants were aged between 7 and 14 years old and had autism with severe behavior problems. They were split into two groups: the first receiving daily CBD for eight weeks prior to eight weeks for placebo following a four-week ‘washout’ period. The second group received the placebo first and then CBD. Behavioral assessments were carried out before and after each treatment phase. A total of 30 participants completed the trial.
Ultimately, CBD was found to be safe and well-tolerated by boys with severe autism and behavioral problems. Clinician impressions further suggested that around two-thirds of the boys displayed evidence of clinical improvement with CBD. While reductions in aggressive behaviors and hyperactivity were most frequently observed, approximately 30% of participants also showed improvements in communication.
Despite this, however, the researchers noted that both the CBD and placebo groups improved to a similar extent on the study's primary outcomes: restricted and repetitive behaviors and scores from the Autism Diagnostic Observation Schedule-2 (ADOS-2), a standardized assessment tool for diagnosing autism in children and adults.
“This study demonstrates the crucial importance of having a placebo group when trying to determine the efficacy of a novel treatment for a condition as complex as autism. We found a robust placebo effect, which would not have been appreciated without a placebo control group,” wrote the researchers in their study.
“Our results call into question the value of such open label studies and stress the importance of families and other raters being blinded to treatment arm,” they concluded.
Sources: Journal of Autism and Developmental Disorders, EurekAlert