Autism spectrum disorder (ASD) is commonly associated with debilitating comorbidities impacting the well-being of affected children and their families. Some children with ASD experience behavioural difficulties that do not respond well to current medications and may also experience unwanted side effects. Therefore, it is crucial to develop alternative, safe and effective therapies. The improved understanding of the endocannabinoid system, together with emerging evidence for the therapeutic effects of cannabis derivatives in neurodevelopment disorders, has led to an exploration of their use in ASD.  This open-label study assessed the efficacy and safety of a novel oil-based full-spectrum medicinal cannabis plant extract 0.08% THC (NTI-164) in treating 14 children with ASD symptoms (13.4 years, range 10-17). Data on the safety profile of NTI-164 was collected through biochemical analysis, vital signs, and parent and participant reports.  The efficacy was assessed through a dose-escalation protocol using a broad range of validated clinical behavioural assessments and parent and child-reported questionnaires.  Following four weeks of treatment with NTI-164, 93% of participants demonstrated significant overall improvement in ASD-related symptoms compared to baseline with transient side effects that did not interfere with their general functioning. In addition, targeted behavioural problems were rated as much improved or very much improved in 46% of the treated patients. More than half of caregivers and children also reported decreased anxiety symptoms.  The findings from this study suggest that NTI-164 is well-tolerated and safe, with potential clinical benefits in improving disruptive behaviours and reducing anxiety in children with ASD-related symptoms. Future longitudinal and well-controlled studies are warranted to develop evidence-based clinical therapies and further evaluate the therapeutic benefit of full-spectrum cannabis extracts in managing ASD core and associated comorbid symptoms in this group of children.

I have read the journal's policy and the authors of this manuscript have the following competing interests: The study was funded by Fenix Innovations.

This study has been registered with the Australian and New Zealand Clinical Trial Registry (Trial ID: ACTRN12621000760875)

Yes

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The details of the IRB/oversight body that provided approval or exemption for the research described are given below:

This study was approved by the Monash Health Human Research Ethics Committee - RES-21-0000-177A

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