CLOZAPINE Response in Biotype-1

This study tests the medication clozapine in people with a specific biological profile (called Biotype-1) of psychotic illness, which includes schizophrenia, schizoaffective disorder, and bipolar disorder with psychotic features. The goal is to see whether clozapine works especially well for this subgroup defined by brain wave patterns. **You may be eligible if...** - You are 18–60 years old - You have been diagnosed with schizophrenia, schizoaffective disorder, or bipolar I disorder with psychotic features - You have significant psychotic symptoms (as measured by the PANSS scale) - You have a normal white blood cell count - You are medically stable - You can read, speak, and understand English **You may NOT be eligible if...** - You have a history of substance abuse in the past month or dependence in the past 3 months - You have a seizure disorder, stroke, or serious brain injury - You have a severe heart condition or AIDS - You have previously taken clozapine or had bad reactions to it - You are pregnant or breastfeeding - You are taking certain medications that affect brain activity (like lithium, anticonvulsants, or benzodiazepines) that cannot safely be stopped Talk to your doctor to see if this trial is right for you.