Abstract
INTRODUCTION: Self-injurious behaviour (SIB) consists of persistent, repetitive movements that can result in serious injury without suicidal intent. These behaviours are prevalent among children with neurodevelopmental disorders, including profound autism. Although many individuals benefit from currently available therapies, some exhibit treatment-refractory SIB that necessitates ongoing use of personal protective equipment and restraint, presumably due to stronger neurobiological drivers. We recently completed a phase I, open-label clinical trial demonstrating the safety, feasibility and preliminary efficacy of bilateral deep brain stimulation targeting the nucleus accumbens (NAc-DBS) in children with profound autism and severe, refractory SIB. The objective of the proposed study is to characterise the effectiveness of NAc-DBS in treating severe, refractory SIB in this unique and vulnerable population. METHODS AND ANALYSIS: A single-centre, randomised double-blinded, crossover trial is proposed. Informed by the results of our pilot study, 25 subjects with autism spectrum disorder and severe, refractory SIB will undergo bilateral NAc-DBS. Following a 4-week recovery period, participants will be randomised to either group A (stimulation ON then OFF) or group B (stimulation OFF then ON). Each block will last 12 weeks, separated by a 2-week washout period. Following completion of the second block, all participants will enter a 6-month open-label phase with stimulation ON. The primary outcome is the difference in the Repetitive Behaviour Scale-Revised total score, between DBS-ON and DBS-OFF conditions. Secondary outcomes include measures of quality of life, caregiver burden, daily logs of SIB events and direct observation of SIB under structured analogues. ETHICS AND DISSEMINATION: The proposed trial has been approved by the institutional Research Ethics Board (1000081171). Trial results will be disseminated through peer-reviewed publications and conference presentations. TRIAL REGISTRATION NUMBER: NCT06529380.