SchizOMICS is a Phase IV, multicenter, dose-flexible, open-label, randomized controlled clinical trial to evaluate the efficacy and safety of aripiprazole versus paliperidone using multi-omics data in patients with a first psychotic episode. The trial will include a total of 244 patients, with two arms of treatment with paliperidone and aripiprazole (1:1).

The main objectives of the study are:

1. To compare the efficacy and safety of aripiprazole and paliperidone in the treatment of first episode psychosis (FEP) subjects in real-world clinical settings at 3 months.
2. To elucidate whether non-responders after 3 months of adequate treatment may display different molecular signatures at baseline based on multi omics data and systems biology analysis.
3. To uncover whether the appearance of side effects after 1 year of adequate treatment may be related to different molecular signatures based on multi-omics data and lifestyle phenotype using systems biology analysis.

Inclusion Criteria:

1. 15-40 years;
2. living in the catchment area;
3. experiencing a first episode of psychosis;
4. no prior treatment with antipsychotic medication or, if previously treated, a total lifetime of adequate antipsychotic treatment of less than 6 weeks;
5. Diagnostic and Statistical Manual of Mental Disorders fth Edition (DSM-5) criteria for schizophreniform disorder, schizophrenia, or schizoaffective disorder.

Exclusion Criteria:

1. meeting DSM-5 criteria for drug dependence;
2. meeting DSM-IV criteria for mental retardation;
3. having a history of neurological disease or head injury.