Lead Sponsor

Pfizer

Age

18 - 65 years

Sex

MALE

Healthy Volunteers

No

•Generally healthy, men and women, aged 18 to 65.
•Hospitalization because of an acute exacerbation of schizophrenia with a diagnosis of schizophrenia established greater than 1 year.
•Ability to remain hospitalized for the duration of the screening period and for 4 weeks of double-blind treatment.

•Current Axis I primary psychiatric diagnosis other than schizophrenia (DSM-IV-TR criteria).
•Current diagnosis or history of substance abuse or dependence (DSM-IV-TR criteria), including alcohol (except for nicotine), within 3 months before baseline (day -1).
•Subjects taking high or chronic doses of benzodiazepine at the screening evaluation who, in the investigator's judgment, would be likely to have severe withdrawal symptoms upon discontinuation.