Combination of NMDA-enhancing and Anti-inflammatory Treatments for Schizophrenia

Inclusion Criteria: * Have a DSM-5 (American Psychiatric Association) diagnosis of schizophrenia * Are resistant to adequate treatments of at least two antipsychotics * Remain symptomatic but without clinically significant fluctuation, while their antipsychotic doses are unchanged for at least 3 months and will be maintained during the period of the 12-week trial * PANSS total score ≥ 70 * Agree to participate in the study and provide informed consent Exclusion Criteria: * DSM-5 diagnosis of intellectual disability or substance (including alcohol) use disorder * History of epilepsy, head trauma, stroke, or serious medical or central nervous system diseases (other than schizophrenia) which may interfere with the study * Clinically significant laboratory screening tests (including blood routine, biochemical tests) * Pregnancy or lactation * Inability to follow protocol