Biomarkers in Clozapine-responding Schizophrenia

This study looks for biological markers (called biomarkers) in the blood and brain of people with schizophrenia who respond well to clozapine — a powerful antipsychotic drug used when other medications haven't worked. Finding these markers could help predict who will benefit from clozapine and lead to better treatments. **You may be eligible if...** - You are between 18 and 65 years old and legally competent - You have been diagnosed with schizophrenia, chronic paranoid psychosis, schizoaffective disorder, or another non-organic psychosis (per ICD-10 criteria) - Your antipsychotic treatment has been stable for the past month - You are considered treatment-resistant (meaning at least 2 prior antipsychotic drugs at adequate doses and durations did not help enough) **You may NOT be eligible if...** - You have not tried at least 2 prior antipsychotic treatments without adequate response - You are not legally competent to consent - Your condition is unstable Talk to your doctor to see if this trial is right for you.