PERFECT(Paliperidone Extended Release(ER)ER efFECTiveness Study to Evaluate the Objective Symptom Change and Symptomatic Remission)

• Various variables will be investigated to evaluate responses : the 8-item of PANSS for schizophrenia for remission
• CGI-SCH-S, I; SCL-90-R; PSP; COWAT; SWN; DAI-10; Sleep-VAS; Vital Signs DIEPSS; LUNSERS; Clinical Lab; Height; weight; waist circumference

The purpose of this open-label, prospective, single arm, 48-week, non-comparative study, starting with paliperidone Extended Release(ER) is to investigate the safety and effectiveness of flexibly dosed paliperidone ER in 252 patients with schizophrenia.

This is an open-label, prospective, single arm, 48-week, non-comparative study, starting with paliperidone ER that is aiming to investigate the safety and effectiveness of flexibly dosed paliperidone ER in 252 patients with schizophrenia.

This study will examine long-term effectiveness and safety on the multidimensional aspects (objective and subjective symptoms) after switching from the existing drug to paliperidone Extended Release(ER) in patients with schizophrenia which is not controlled by the existing drug. This study has a limit in that it is designed as an open-label study, but can find the use pattern of paliperidone ER, which its effectiveness was already proven, in clinical practice because it targets representative patients. This study also will be useful data for clinicians because it will evaluate the effectiveness including remission rates in case of a long-term treatment. The study will especially classify the causes of failure for the existing antipsychotic therapies and inspect effectiveness and safety of paliperidone ER and whether those failures can be resolved. This study is more meaningful in that it will apply the remission criteria in patients with schizophrenia defined by Andreasen et al. in 2005 for the purpose of evaluating long-term therapeutic effectiveness.

The primary objective of this study is to examine whether the symptom is improved or changed after switching from the previous oral antipsychotic to flexibly dosed paliperidone ER. The primary endpoints are the changes in total and partial score of positive and negative symptoms (PANSS). The secondary objectives of the study are as follows; (1) Various variables will be investigated to evaluate responses after switching from previous oral antipsychotic medication to flexibly dosed paliperidone ER : Assessment of the 8-item of PANSS for schizophrenia for remission, General measures of treatment success, symptom check list-90-revised(SCL-90-R), Personal and social functioning, subject's Executive Function, subjective well-being of patients taking Neuroleptics.;(2)To explore the tolerability and safety of paliperidone ER, following variables will be assessed : vital signs, Drug-Induced Extrapyramidal Symptoms Scale, Liverpool University neuroleptic side effect rating scale (LUNSERS), weight and circumference of waist, clinical Laboratory test and adverse events (AEs) The recommended dose of paliperidone Extended Release(ER) oral tablet is 6 mg once daily. For some patients, the dose can be increased or decreased within the recommended range of 3 to 12 mg. During the study period(24 week), the flexible dose of paliperidone ER within a range of 3 to 12 mg can be administered daily. Since this study is a flexible-dose study, the investigator can adjust the dose proper to each patient.

Inclusion Criteria:

• Childbearing potential women who consent to the use of the consistently permissible contraception (oral contraceptive, contraceptive injection, intrauterine device, double barrier method and contraceptive patch)
• Patients who are compliant with self-medication or can receive consistent help or support
• Patients who need to change the antipsychotic drug to another one for the following reasons among the patients treated with an antipsychotic drug for more than two weeks before the screening (1)Group of lack of efficacy - The antipsychotic drug is clinically required to be changed because there is no or little therapeutic response despite the appropriately dosed antipsychotic therapy (2) Group of lack of tolerance - The antipsychotic drug is required to be changed due to lack of tolerance to the existing antipsychotic drug or the safety issue (3) Group of lack of compliance - The antipsychotic drug is required to be changed due to lack of medication compliance or the patient wants to change the antipsychotic drug)

Exclusion Criteria:

• Patients with the past history of neuroleptic malignant syndrome (NMS)
• Patients who are suspicious of having clinically significant risk including suicide or aggressive behavior and are expected to unable to complete the study(based on the investigator's judgment)
• Patients with severe preexisting gastrointestinal narrowing (pathologic or iatrogenic) or patients who cannot swallow the drug whole (The study drug must not be chewed, divided, melted or grinded because it can impact the study drug release profile.)
• Patients with significant abnormal findings in blood chemistry, hematological and urine analyses which are clinically significant at the investigator's discretion
• Female patients who are pregnant or are breast feeding