Key inclusion criteria include:
- Have a current diagnosis of schizophrenia.
- Increase in symptoms over the past 2-4 weeks.
- Willing to remain inpatients for the duration of the trial.
- Subjects with a current DSM-IV axis I diagnosis other than schizophrenia
- Subjects who meet the DSM-IV criteria for psychoactive substance abuse and dependence
- Subjects with a history of treatment resistant schizophrenia
- Females of childbearing potential