Inclusion Criteria:
* Subject has signed informed consent;
* Current DSM-IV-TR diagnosis of schizophrenia;
* Clinically stable on the same single second-generation antipsychotic for the past 8 weeks;
* Meets study-specific PANSS criteria;
* Willing and able to cooperate with cognitive testing
* Females are not pregnant, not breast-feeding;
* Females are post-menopausal or surgically sterile or practicing birth control;
* Males are surgically sterile or agree to be sexually inactive or use barrier method of birth control
Exclusion Criteria:
* Subject has a substance dependence disorder that has not been in sustained remission for at least 1 year;
* Diagnosis of schizoaffective disorder;
* Bipolar disorder, manic episode, dementia, OCD, or drug-induced psychosis or current major depressive disorder;
* Diagnoses with mental retardation; acute psychosis hospitalization within past 6 months;
* Current clozapine treatment; suicidal ideation or behavior;
* BMI of 39 or greater; current homicidal or violent ideation;
* Medical or CNS condition other than schizophrenia that could affect cognitive performance or testing; relevant drug sensitivity or allergy; positive urine screen for alcohol or drugs of abuse;
* Positive hepatitis or HIV test result;
* Recent clinically significant illness/infection or surgery;
* Recent blood product transfusion, donation or loss of 5 mL/kg of blood;
* Visual, hearing or communication disability
