A Study of Paliperidone Palmitate 3 Month Formulation for the Treatment of Patients With Schizophrenia

• The time to first relapse event in the Double-blind Phase [ Time Frame: Approximately 6 months ] [ Designated as safety issue: No ]
  Time to relapse is defined as the time between randomization to treatment in the Double-Blind Phase and the first documentation of a relapse.
  
  

• The change from baseline to endpoint in Positive and Negative Syndrome Scale (PANSS) (total and subscales) in the Double-blind Phase [ Time Frame: Baseline and approximately 6 months ] [ Designated as safety issue: No ]
  The PANSS scale provides a total score (sum of the scores of all 30 items) and scores for 3 subscales, the positive subscale (7 items), the negative subscale (7 items), and the general psychopathology subscale (16 items). Each item is rated 1 (absent) to 7 (extreme).
  
  
• The change from baseline to endpoint in Clinical Global Impression Severity (CGI-S) scale in the Double-blind Phase [ Time Frame: Baseline and approximately 6 months ] [ Designated as safety issue: No ]
  The CGI-S rating scale is used to rate the severity of a patient's overall clinical condition on a 7-point scale ranging from 1 (not ill) to 7 (extremely severe).
  
  
• The change from baseline to endpoint in Personal and Social Performance (PSP) scale in the Double-blind Phase [ Time Frame: Baseline and approximately 6 months ] [ Designated as safety issue: No ]
  The PSP scale measures personal and social functioning in the domains of: a) socially useful activities, b) personal and social relationships, c) self-care, and d)disturbing and aggressive behavior.
  
  

This is a randomized (the study drug is assigned by chance), double blind (neither physician nor patient knows the treatment that the patient receives), parallel group (each group of patients will be treated at the same time), placebo-controlled (an inactive substance is compared with a drug to test whether the drug has a real effect in a clinical trial) multicenter study. The study consists of 4 phases: a Screening Phase (up to 3 weeks); a 17-week flexible dose open-label Transition Phase (open-label phase means that all people know the identity of the intervention); a 12-week fixed dose open-label Maintenance Phase; and a randomized, double-blind, fixed dose, placebo-controlled relapse prevention phase (referred to as the Double-blind Phase). Patients who meet specific stabilization criteria will enter the Double-blind Phase at Week 29. Patients will be randomly assigned, in a 1:1 ratio, to receive either a fixed dose of PP3M or placebo. The Double-blind Phase will be of variable duration; patients will remain in the study until they experience a relapse event or meet discontinuation criteria.