About 1 in 59 children in the United States has autism spectrum disorder, according to the Centers for Disease Control and Prevention (CDC). Autism spectrum disorder is defined as a spectrum of neurodevelopmental disorders characterized by core deficits in communication and reciprocal social interaction, as well as restricted and repetitive patterns of behaviors or interests. There are no psychotropic medications approved for treating the irritability that often co-occurs with autism spectrum disorder. There are also no medications available to treat the core symptoms of the disorder.

In 2018, Francisco X. Castellanos, MD, the Brooke and Daniel Neidich Professor of Child and Adolescent Psychiatry, and professor of radiology and neuroscience and physiology, began laying the groundwork for a study of a promising new therapy: cannabidiol (CBD), a nonpsychoactive component of marijuana.

Incorporating Cannabidiol (CBD) into Treatment Plans

NYU Langone Health has been at the forefront of investigating the use of this cannabinoid for other disorders. Research by Orrin Devinsky, MD, director of NYU Langone’s Comprehensive Epilepsy Center and professor of neurology, neurosurgery, and psychiatry, led to Food and Drug Administration (FDA) approval of the CBD extract Epidiolex® for treatment of seizures associated with Dravet and Lennox-Gastaut syndromes, two rare and severe forms of epilepsy; the Drug Enforcement Administration (DEA) subsequently reclassified Epidiolex® from Schedule I to Schedule V, making it accessible without the onerous restrictions placed on other cannabis-related substances. NYU Langone researchers are also testing CBD for treatment of alcohol use disorder and post-traumatic stress disorder.

Dr. Castellanos’ interest in CBD as a potential therapy for autism spectrum disorder emerged from his collaboration with Dr. Devinsky; Richard Tsien, PhD, the Druckenmiller Professor of Neuroscience and Physiology, director of the Neuroscience Institute, and professor of neurology; and Helen L. Egger, MD, the Arnold Simon Professor of Child and Adolescent Psychiatry and chair of the Department of Child and Adolescent Psychiatry. CBD is believed to affect some of the same neurochemical pathways—including those of the body’s endocannabinoid system—that have been increasingly implicated in autism spectrum disorder. Preliminary results from a retrospective open-label study in Israel show significant reductions in self-injury, outbursts, hyperactivity, and anxiety in children with autism spectrum disorder treated with a high-CBD cannabis extract; no severe adverse effects were observed.

In another small preliminary study, patients with Fragile X syndrome, a genetic condition in which autism spectrum disorder frequently co-occurs, also showed beneficial responses. And in a mouse model study of Dravet syndrome, animals showed improvement in social interactions and anxiety when given low doses of CBD—though those benefits disappeared at levels high enough to prevent seizures.

Testing CBD Use for Autism Spectrum Disorder Symptoms

Dr. Castellanos recently submitted an Institutional Review Board proposal for a 10-week open trial of Epidiolex® in children with autism spectrum disorder, aimed at determining which symptoms are most affected and what dosage is optimal. “We expect that anxiety may improve, which would be quite a substantial benefit, since many children with autism are also excessively anxious,” he explains. “However, we also want to see if the ability to interact with others is also enhanced, as that would represent the first medication treatment for a core symptom of autism. That would be a major win.”