Synbiotic Compound to Reduce Symptoms of Schizophrenia

Inclusion Criteria: * Age 18-65, inclusive. * Capacity for written informed consent. * Diagnostic and Statistical Manual of Mental Disorders, 5th Edition (DSM-5) diagnosis of schizophrenia or schizoaffective disorder (APA 2013) as determined by the Structured Clinical Interview for DSM-5 Disorders (SCID-5). * Outpatient at the time of enrollment. * Residual psychotic symptoms of at least moderate severity as evidenced by a Positive and Negative Syndrome Scale (Kay et al., 1987) (PANSS) total score of 60 or higher AND one or more of the following: one or more PANSS positive symptom scores of 4 or higher; OR containing at least three positive or negative items with scores of 3 or higher at the screening visit. * Receiving antipsychotic medication for at least 8 weeks prior to starting the study with no medication changes within the previous 21 days. * Proficient in the English language. Exclusion Criteria: * DSM-5 diagnosis of intellectual disability or comparable diagnosis determined by previous versions of the DSM. * Any clinically significant or unstable medical disorder as determined by the investigators, including congestive heart failure, liver disease, renal failure, any diagnosis of cancer undergoing active treatment. * A primary immunodeficiency condition such as HIV infection, or undergoing cancer chemotherapy, or receiving systemic corticosteroids, methotrexate or monoclonal antibodies for treatment of an autoimmune disorder. * History of IV drug use. * DSM-5 diag…