There is currently no clinically validated treatment that reduces the risk of psychosis onset or mitigates the severity of a first psychotic episode in individuals at clinical high risk for psychosis (CHR-P). CHR-P is associated with attenuated psychotic symptoms, functional decline, and high rates of affective symptoms, including a comorbid mood disorder prevalence of 40% or higher. Repetitive transcranial magnetic stimulation (rTMS) targeting the left dorsolateral prefrontal cortex (LDLPFC) is an established treatment for depression and is increasingly supported for negative symptoms in psychotic disorders, making it a promising low-burden candidate for early intervention in CHR-P.
This pilot study evaluates an accelerated intermittent theta burst stimulation (iTBS) protocol, delivered over five consecutive days, in individuals at CHR-P (SIPS-confirmed, aged 18-34). Forty participants will be randomized 1:1 to active accelerated iTBS or sham stimulation to the LDLPFC, using standard scalp-based (BEAM-F3) targeting rather than MRI-guided neuronavigation, reflecting the pilot nature and funding constraints of this early-phase study.
Given the variable incidence of and long latency to psychosis onset in the CHR-P population, this study also incorporates a battery of neurocomputational tasks (analyzed using Hierarchical Gaussian Filter modeling) and a multimodal digital phenotyping framework (wearables, smartphone-based passive sensing, facial/vocal affect analysis, and structured speech analysis) to assess candidate biomarkers of treatment response.
Primary outcomes are the safety, feasibility, and tolerability of the accelerated protocol in this population. Secondary outcomes include the sensitivity of neurocomputational biomarkers to treatment and change in depressive symptoms. Exploratory outcomes include treatment-related change across multiple domains of real-world functioning captured through digital phenotyping. This study is not designed to establish definitive treatment efficacy but to inform the design of future, adequately powered trials.
