This is an open-label (patients and study staff will know the identity of treatments assigned) study of paliperidone palmitate in patients with acute an exacerbation of schizophrenia. The total duration of the study will be approximately 4 months. Eligible patients without a documented history of exposure to oral risperidone or paliperidone extended-release (ER), or intramuscular (IM) RISPERDAL CONSTA or paliperidone palmitate will receive oral risperidone 1 mg/day or extended release (ER) OROS paliperidone 3 mg/day for at least 3 days before the first injection of the study drug (paliperidone palmitate) for tolerability testing. Paliperidone palmitate will be administered to patients as an intramuscular (IM) injection in the deltoid (upper arm) or gluteal (buttocks) muscle.
The purpose of this study is to explore the efficacy of paliperidone palmitate administered as a once monthly injection in patients with an acute exacerbation of schizophrenia.