A Study of Flexibly Dosed Paliperidone Extended Release Tablets in Participants With Schizophrenia

The purpose of this study is to evaluate the effectiveness of paliperidone extended-release (ER; designed to slowly release a drug in the body over an extended period of time) tablets in participants with schizophrenia (psychiatric disorder with symptoms of emotional instability, detachment from reality, often with delusions \[a false belief held in the face of strong differing evidence, especially as a symptom of psychiatric disorder\] and hallucinations \[imagining things\], and withdrawal into the self) who were not satisfied with other prior antipsychotics (agents that control agitated psychotic behavior, alleviate acute psychotic states, reduce psychotic symptoms, and exert a quieting effect; olanzapine, quetiapine and risperidone) they had been taking. The safety and tolerability of paliperidone ER tablets will also be assessed.

This is an open label (all people know the identity of the intervention), prospective (study following participants forward in time), non-randomized (the study drug is not assigned by chance, participants may choose which group they want to be in, or they may be assigned to the groups by the researchers), single-arm (getting one dose of medicine) and multi-center (when more than one hospital or medical school team work on a medical research study) study designed to determine the efficacy, tolerability and safety of flexible dosage of paliperidone ER tablets in treatment of participants with schizophrenia not satisfied with other prior antipsychotics. The duration of the study will be 12 weeks. All participants will be given paliperidone ER 3 milligram (mg) or 6 mg or 9 mg or 12 mg oral (by mouth) tablets depending on Investigator's discretion once daily for 12 weeks; initial dose for paliperidone ER will be 6 mg/day. The primary objective will be to evaluate the efficacy of treatment with paliperidone ER using Positive and Negative Symptom Scale (PANSS) total scores. Participants safety and tolerability will be monitored throughout the study.

Eligibility Criteria:
Inclusion Criteria:

* Participants meeting Diagnostic and Statistical Manual of Mental Disorders-IV (DSM-IV) diagnosis criteria of schizophrenia
* Participant receiving full course of treatment (6-8 weeks) at correct dose (dose range recommended by the instruction) of Risperdal, Zyprexa or Seroquel before enrollment, was poorly controlled and had to change medication because of unsatisfying efficacy, tolerability or safety issues, or other reason
* Participant in the non-acute phase during screening received treatment with any of above three antipsychotics within 4 weeks before enrollment and state of illness was relatively stable
* 7. Female participants must be postmenopausal for at least 1 year, surgically sterile, abstinent, or, if sexually active, agree to practice an effective method of birth control before entry and throughout the study. Effective methods of birth control include prescription hormonal contraceptives, contraceptive injections, intrauterine devices, double barrier method, contraceptive patch and male partner sterilization. Female participants must also have a negative urine pregnancy test at screening
* Participant willing to and who could complete questionnaire by himself

Exclusion Criteria:

* Participant receiving treatment with clozapine or risperidone microspheres for injection (Hengde) within 3 months before screening
* Participant having history of seizure except febrile convulsion (seizures that occur during a febrile episode \[fever\])
* Participant having refractory schizophrenia (previous treatment with unsatisfied efficacy of 2 or more than 2 kinds of antipsychotics with different chemical structure after adequate dose and duration)
* Participant receiving electric shock treatment within 1 month before screening
* Participant having serious, unstable physical diseases