Schizophrenia is associated with long-lasting health, social and financial burden for patients, families, caregivers and society. According to the World Health Organization, this burdensome illness is one of the top 10 causes of disability in developed countries. The costs associated with hospitalization, lifelong treatment and loss of productivity lead to a great economic burden. In Canada, the total annual costs associated with schizophrenia are over $10 billion. The main reason for this heavy burden is that 25-30% of schizophrenia patients respond very poorly to antipsychotic medication. Moreover, psychotherapeutic treatment alternatives are very limited for this suffering population. This unmet clinical need requires innovation and action. Psychotherapeutic treatment alternatives such as Cognitive Behavior Therapy (CBT) are very limited and provide at best moderate results. Virtual reality (VR) opens new exciting avenues to treat this illness. With immersive VR, our team recently tested a novel psychotherapeutic intervention, Avatar Therapy (AT), where the therapist engages in a dialogue with the patient through a virtual representation of their distressing voice. This relational and experiential approach offers a unique opportunity to help patients gain control over their voice. The preliminary results of our randomized-controlled trial (RCT) pilot showed a large effect on auditory verbal hallucination for AT and a moderate effect for CBT. The main goal of the currently proposed RCT study will be to examine if AT is superior to CBT for the treatment of chronic auditory hallucinations in schizophrenia. As evidence-based therapeutic options are limited for this burdensome illness and provide only modest symptomatic relief, the current trial will contribute to the validation of a novel approach answering a fundamental clinical need. The demonstration of the superior efficacy of AT would be a great breakthrough and will open new avenues to clinical treatment.

Schizophrenia is associated with long-lasting health, social and financial burden for patients, families, caregivers and society. According to the World Health Organization, this burdensome illness is one of the top 10 causes of disability in developed countries. The costs associated with hospitalization, lifelong treatment and loss of productivity lead to a great economic burden. In Canada, the total annual costs associated with schizophrenia are over $10 billion. The main reason for this heavy burden is that 25-30% of schizophrenia patients respond very poorly to antipsychotic medication. Moreover, psychotherapeutic treatment alternatives are very limited for this suffering population. This unmet clinical need requires innovation and action. Psychotherapeutic treatment alternatives such as Cognitive Behavior Therapy (CBT) provide at best moderate results. Using immersive virtual reality, our team recently tested a novel psychotherapeutic intervention, Avatar Therapy (AT), where the therapist engages in a dialogue with the patient through a virtual representation of the patient's distressing voice. This approach, being both relational and experiential, provides a unique opportunity to aid patients gain control over their voice. The results of our pilot study on AT were clinically promising for the severity and distress related to hallucinations, positive symptomatology and emotion regulation. The preliminary results of our small pilot randomized-controlled trial showed a large effect of AT on auditory verbal hallucination, while a moderate effect was found for our adapted short CBT for hallucinations. To further research in this field, the primary goal of this single-blinded randomized-controlled, single-site parallel study is to show that AT is superior to CBT for the treatment of persistent auditory hallucinations in schizophrenia. The secondary goal is to examine the effects of these interventions on emotion regulation, mood symptoms (anxiety and depression), self-esteem, level of functioning and quality of life. To do so, each treatment group will include 68 participants over 18 years of age hearing persecutory voices and suffering from treatment resistant schizophrenia or schizoaffective disorder. AT comprises of 9 weekly sessions: 1 avatar creation session and 8 therapeutic sessions, where the patients are confronted to their reproduced hallucinatory experience and are encouraged to enter in a dialogue with their virtual persecutor. CBT includes 9 weekly sessions consisting of learning modules and task assignments. Subjects will be evaluated at pre- and post-treatment. Follow-ups will be ensured at 3, 6 and 12 months to assess primary (auditory hallucination) and secondary outcomes. Mixed model analyses will be performed to measure and compare the effects of both interventions. As evidence-based therapeutic options are limited for this burdensome illness and provide only modest symptomatic relief, the current trial will contribute to the validation of a novel approach answering a fundamental clinical need. Ultimately, the demonstration of the superior efficacy of AT would be a great breakthrough and will open new avenues to clinical treatment.

Inclusion Criteria:

• DSM-5 diagnosis of schizophrenia or schizoaffective disorder
• Distressing auditory verbal hallucinations
• Did not respond to 2 antipsychotic trials
• Stable doses of medication during the last 2 months prior to enrollment

Exclusion Criteria:

• Substance use disorder within the last 12 months
• Neurological disorder
• Intellectual disability
• Unstable and serious physical illnesses
• Experiencing an acute psychotic episode
• Cognitive Behavioral Therapy for psychosis within the last 12 months

The therapists, the study coordinator and the participants will be aware of the interventions after the allocation randomization. The principal investigators and independent evaluators will be blind to the random allocation conditions. The evaluators will be separated from the therapists by working at a separate location on the hospital grounds and will sign agreements not to discuss cases with any other team member. Management of the evaluations will be delegated to a coordinator preventing any direct contact between the investigators and the independent evaluators.