Comparison of Paliperidone Palmitate and RISPERDAL CONSTA in Patients With Schizophrenia

Inclusion Criteria: * Meet diagnostic criteria for schizophrenia according to Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) criteria as specified by the protocol for at least 1 year before screening * Prior medical records, written documentation or verbal information obtained from previous psychiatric providers obtained by the investigator must be consistent with the diagnosis of schizophrenia * A total PANSS score between 60 and 120, inclusive, at screening and baseline; Body mass index (BMI) at the screening visit BMI at least 17 kg/m2 * Female patients must be postmenopausal for at least 2 years, surgically sterile, abstinent, or, if sexually active, be practicing an effective method of birth control before study entry and throughout the study as specified by the protocol. Women of childbearing potential must have a negative serum beta-human chorionic gonadotropin (b hCG) pregnancy test result at screening. Exclusion Criteria: * Patient unable to provide consent or involuntarily committed to psychiatric hospitalization; A primary, active DSM-IV diagnosis on Axis I other than schizophrenia * A DSM-IV diagnosis of active substance dependence within 3 months before screening (nicotine and caffeine are not exclusionary) * History of treatment resistance as defined by failure to respond to 2 adequate treatments with different antipsychotic medications (an adequate treatment is defined as a minimum of 6 weeks at maximum tolerated dosage) * Relevant history or current presence of any significant or unstable cardiovascular, respiratory, neurologic (including seizures or significant cerebrovascular disease), renal, hepatic, hematologic, endocrine, immunologic, or other systemic disease including history of neuroleptic malignant syndrome; History of any severe pre-existing gastrointestinal narrowing or inability to swallow oral study drug whole with the aid of water (applies to those patients requiring oral tolerability only) * Significant risk of suicidal or violent behavior, as clinically assessed by the investigator ; History of life-threatening allergic reaction to any drug; Known or suspected hypersensitivity or intolerance to risperidone, paliperidone, 20% Intralipid, or any of their excipients (e.g., soybean oil, egg yolks, phospholipids, and glycerol) * Have received an experimental drug or experimental biologic, or used an experimental medical device within 6 months before screening; History of any active malignancy within the previous 5 years, with the exception of basal cell carcinomas * Women who are pregnant or breast-feeding or are planning to become pregnant uring the study