Efficacy and Safety Study for Cognitive Deficits in Adult Subjects With Schizophrenia

* Has current DSM-IV-TR diagnosis of schizophrenia confirmed by the Mini-International Neuropsychiatric Interview. * Is clinically stable while receiving antipsychotic therapy with one or two atypical antipsychotic medications: lack of hospitalizations from 4 months of Initial Screening Visit; taking same antipsychotic medication(s) for at least 8 weeks prior to the Day -1 visit; core positive symptoms of PANSS no worse than moderate in severity throughout Screening Period of at least 4 weeks. * Has been diagnosed with or treated for schizophrenia for at least 2 years prior to Initial Screening Visit. * Has had continuity in psychiatric care (e.g., mental health system, clinic or physician) for at least 6 months prior to Initial Screening Visit. * Has an identified responsible contact person (e.g., family member, social worker, case worker, or nurse) that can provide support to the subject and ensure compliance with protocol requirements.

* Has valid current or past diagnosis of schizoaffective disorder, bipolar disorder, manic episode, dementia, posttraumatic stress disorder, obsessive compulsive disorder, or a current major depressive episode. * Has history of substance abuse (excluding nicotine or tobacco products) or alcohol abuse within 6 months prior to Screening Visit; has a substance dependence disorder (excluding nicotine or tobacco products) that has not been remitted for at least 1 year prior to Initial Screening Visit. * Is taking any medication for extrapyramidal symptoms at any time from the Initial Screening Visit until the Day -1 Visit. * Is taking any antidepressant that is excluded, including tricyclic antidepressants and monoamine oxidase inhibitors, at any time from 8 weeks prior to the Day -1 Visit. * Has significant suicidal ideation at Initial Screening Visit. * Has had a suicide attempt within 1 year prior to the Day -1 Visit. * Has participated in another trial utilizing the MATRICS Consensus Cognitive Battery (MCCB) or UCSD Performance-Based Skills Assessment (UPSA) (any version) within 6 months prior to Initial Screening Visit. * Is currently enrolled in any form of cognitive remediation training.