PASS(PAliperidone Effectiveness Study to Evaluate the Subjective Symptom Change)

• To examine whether the efficacy for subjective symptoms is improved or maintained after switching from the previous oral antipsychotic to flexibly dosed paliperidone ER. The primary endpoints are the total score of the symptom checking list (SCL-90-R) [ Time Frame: During this study(24 weeks), primary outcome will be measured 8 times(Baseline, 1-week, 2-week, 4-week, 8-week, 12-week, 16-week, 24-week) ] [ Designated as safety issue: No ]
  

• Various variables will be investigated to evaluate responses: Krawiecka scale, CGI-SCH-S, I, PSP, COWAT, SWN, Sleep-VAS, Vital Signs DIEPSS, Clinical Lab, Height, weight, waist circumference [ Time Frame: During this study(48 weeks), secondary outcomes will be measured 8 times(Baseline, 1-week, 2-week, 4-week, 8-week, 12-week, 16-week, 24-week) ] [ Designated as safety issue: No ]
  

Although the control of positive symptoms is often regarded as the primary goal of treatment in schizophrenia, subjective experience has been increasingly considered as important objective of treatment. As many patients suffering from psychotic disorders frequently experienced disturbed thinking as well as cognitive disorders, clinicians have been suspicious of the subjective assessments of patients when evaluating treatment outcomes. Traditionally, the study of subjective symptoms of schizophrenic patients has been limited to delusion and hallucinations and the non-subjective aspects of therapeutic drugs have been thoroughly studied (efficacy, side-effects and action mechanisms), while other abnormal subjective experiences of illness have been rather neglected (Rossi et al., 2000).

However, schizophrenia is a chronic disease and maintenance of the drug and rehabilitation have an absolute impact on patients' quality of life and function. One of the biggest decision factors of those maintenance and rehabilitation is patients' subjective experience about symptoms. Therefore, the patients' subjective symptom improvement as well as the therapist-evaluated objective symptom improvement is expected to function as an important factor for a long-term prognosis.

SCL-90-R(Symptom Check List - 90 - Revised) was developed in 1994 as the revised version of SCL-90 (Derogatis. 1994). This 90-item scale is widely used to check overall psychopathology and general symptoms. Each item is evaluated by a subject according to the severity of the subjective symptom he/she experienced over the past one week on a scale of 0 to 4 (0 point - none, 4 points - extremely severe). This scale includes a total of nine symptoms including somatization, obsessive-compulsive symptoms, interpersonal sensitivity, depression, anxiety, hostility, phobic-anxiety, paranoid ideation, and psychoticism. This study does not focus on SCL-90-R, but the domestic clinical study of patients with schizophrenia (Joo et al. 2001) reported that the scores of K-FBF: Frakfurter Beschwrde-Fragebogen (Süllwold, 1986) specially designed for the schizophrenia patients' experience of patient symptoms showed stronger relation with SCL-90-R scores, the report of subjective symptom experience, than objective symptom scales including PANSS(Positive and Negative Symptom Scale) .

This study will replace the previous drug with paliperidone ER in patients with schizophrenia who were not successfully treated with other antipsychotics and examine the multidimensional aspects of the results by utilizing subjective experience scale and objective symptom scale.

This study is a 24-week, multi-center, open-label, prospective, non-comparative study. The primary objective of this study is to examine whether the efficacy for subjective symptoms is improved or maintained after switching from the previous oral antipsychotic to flexibly dosed paliperidone ER. The primary endpoints are the total score of the Symptom Check List-90-Revised(SCL-90-R). 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. For the purpose, following variables will be assessed : Krawiecka scale, general measures of treatment success, personal and social functioning, subject's executive function and Subjective well-being under neuroleptics; (2)To explore the tolerability and safety of paliperidone ER, following variables will be assessed : vital signs, Drug-Induced Extrapyramidal Symptoms Scale (DIEPSS), body weight and circumference of waist, clinical laboratory test and adverse events. 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.