For schizophrenic patients who remained in remission while on maintenance medication, there may come a point in time when the relative risk for relapse become so low that discontinuation of therapy can be considered. This study is to investigate whether that point in time is reached in 12 months following the first episode illness. Moreover, it also aims to identify other predictors of relapse as well as to evaluate the costs and benefits of maintenance therapy.

Inclusion Criteria:

• Male or female patients, from 18 to 65 years of age at Visit 1
• Patients must achieve a level of understanding and expressive capacity sufficient to communicate adequately with the study coordinator and to participate in cognitive testing.
• Patients must agree to cooperate with all tests and examinations required by the protocol. They must be willing to comply fully with treatment
• Patient must understand the nature of the study and must sign an informed consent document.
• Patients must be Cantonese speaking Han Chinese
• Patients must be diagnosed, according to the SCID for DSM-IV, with schizophrenia, schizoaffective disorder or schizophreniform psychosis.
• Patients must have good response to anti-psychotic treatment by achieving a rating of 2 or below in Clinical Global Impression Scale (CGI) Severity of illness; a rating of 4 or below in Improvement scale, and a rating of 3 or below in (conceptual disorganization, unusual thought content), a rating of 2 or below in (delusion, hallucinatory behavior) and a rating of 4 or below in (Suspiciousness) of Positive and Negative Syndrome Scale (PANSS) for at least 8 weeks

Exclusion Criteria:

• Female patients who are either pregnant or lactating.
• Patients previously on clozapine should be excluded from the study
• Significant medical illnesses including seizures.
• DSM-IV substance (alcohol or other drugs) abuse or dependence within the past 3 months.
• Judged clinically to be at serious suicidal risk.
• Treatment with an injectable depot neuroleptic within less than one of the patient's dosing intervals between depot neuroleptic injections prior to study entry.