A Randomized, Active-controlled, Double-blind, Parallel-Goup Study of the Efficacy and Safety of Extended Release(ER) Paliperidone in the Treatment of Schizophrenia

This is a randomized (patients are assigned different treatments based on chance), double-blind (neither the patient nor the physician knows whether drug or placebo is being taken, or at what dosage), active-controlled, flexible-dose, parallel group, multicenter study. The study consists of a screening phase, a double-blind treatment phase (6 weeks) and a safety follow-up phase (1 week). The patients in this study will be randomized to 1 of 2 treatment groups to receive extended release OROS paliperidone or Olanzapine once daily for the 6-week double-blind treatment phase. Randomization will occur in a ratio of 1 (extended release OROS paliperidone) to 1 (Olanzapine). Patients must be hospitalized at least 14 days after entry. Those who receive extended release OROS paliperidone will start at a dosage of 6 mg taken daily, dose may be titrated up by 3mg/day every 7 days, or down rapidly based on the balance of efficacy (effectiveness of drug) and safety/tolerability assessed by the investigator. After the initial 7 days, dose could be flexible within 3-12mg/day. Those who receive olanzapine will start at a dosage of 5mg taken daily, dose may be titrated up by 5mg/day every 7 days, or down rapidly based on the balance of efficacy and safety/tolerability assessed by the investigator. After the initial 7 days, dose could be flexible within 5-15mg/day. Efficacy parameters include Positive and Negative Symptom Scale (PANSS) score, Clinical Global Impression-Severity (CGI-S) and Personal and Social Performance (PSP) score per assessment visit. The primary efficacy is the change in PANSS from baseline to the last post-randomization assessment. Safety assessments include the adverse events, changes in physical examination, vital signs, laboratory tests at pretreatment and posttreatment.