Phase 4 Study to Evaluate Efficacy of Paliperidone Extended-Release(ER) in Schizophrenic Participants

An Open-label Prospective, Non-comparative Study to Evaluate the Subjective Experiences Upon Transition to Paliperidone Extended Release(ER) in Subjects With Schizophrenia

The purpose of this study is to investigate the efficacy of flexibly dosed paliperidone extended-release (mechanism to dissolve a drug over time in order to be released slower and steadier into the blood stream) in improving or maintaining the subjective symptoms of the participants in three participants' groups (that is, by the reason to switch: lack of efficacy group, lack of tolerability group, and lack of compliance group) who switched from other previous antipsychotic drugs to paliperidone extended-release tablets at flexible doses.

This is an open-label (all people know the identity of the intervention), prospective (study following participants forward in time), single arm, and non-comparative study of paliperidone Extended-release (ER) in participants switching from the previous oral antipsychotic to flexibly dosed paliperidone ER. The total study duration will be approximately of 24 weeks per participant. The study consists of 2 parts: Screening (that is, 14 days before study commences on Day 1); Treatment (24 weeks). Efficacy will primarily be evaluated by change from baseline in symptom checklist 90-R (SCL90-R) at Week 24. Participants' safety will be monitored throughout the study.

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)
• Participants who are compliant with self-medication or can receive consistent help or support
• Participants who need to change the antipsychotic drug to another one for the following reasons among the participants 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 participant wants to change the antipsychotic drug)

Exclusion Criteria:

• Participants with the past history of neuroleptic malignant syndrome (NMS)
• Participants 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)
• Participants with severe preexisting gastrointestinal narrowing (pathologic or iatrogenic) or participants 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
• Female participants who are pregnant or are breast feeding
• Participants who have participated in any investigational drug trial within 1 month prior to the screening visit