The objective of this study is to evaluate the efficacy and safety of cariprazine relative to placebo in the prevention of relapse of symptoms in participants with schizophrenia.

There were 3 periods (phases) in the study. The Open-label Phase lasted 20 weeks. In the first 6 weeks, participants received 3, 6, or 9 mg cariprazine orally once a day; the dose could be modified during this time. The cariprazine dose was fixed at 3, 6, or 9 mg for the last 14 weeks of this Open-label Phase. At the end of Week 8, participants had to meet the following criteria to continue in the study.

• Positive and Negative Syndrome Scale (PANSS) total score ≤ 60 at the end of Week 8
• At least 20% decrease in PANSS total score from baseline to the end of Week 8
• Clinical Global Impressions - Severity (CGI-S) score ≤ 4 at the end of Week 8
• Score of ≤ 4 on each of the following 7 PANSS items: P1, P2, P3, P6, P7, G8, and G14 at the end of Week 8
• Stable dose during the previous 2 weeks
• No significant tolerability issues as judged by the Investigator at the end of Week 8

At the end of the Open-label Phase, participants were randomized into 2 treatment groups, cariprazine or placebo, if they met the following criteria:

• PANSS total score ≤ 60 at the end of Week 20
• At least 20% decrease in PANSS total score from baseline to the end of Week 20
• CGI-S score ≤ 4 at the end of Week 20
• Score of ≤ 4 on each of the following 7 PANSS items: P1, P2, P3, P6, P7, G8, and G14 at the end of Week 20
• No significant tolerability issues as judged by the Investigator During this Double-blind Treatment Phase, participants received either placebo or cariprazine at the same dosage (3, 6, or 9 mg) that they received during the last 14 weeks of the Open-label Phase.

All participants entered the 4 week Safety Follow-up Phase. They received a treatment other than the investigational product at the discretion of the Investigator.

Inclusion Criteria:

• Participants who have provided informed consent prior to any study specific procedures.
• Participants currently meeting the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition - Text Revision (DSM-IV-TR) criteria for schizophrenia.
• Participants with normal physical examination, laboratory, vital signs, and/or electrocardiogram (ECG).
• Diagnosis of schizophrenia for a minimum of 1 year before Visit 1 (Screening).
• Positive and Negative Syndrome Scale (PANSS) total score ≥ to 70 and ≤ 120 at Visit 1 (Screening) and Visit 2 (beginning of Run-in Phase).
• Negative serum B-human chorionic gonadotropin (B-hCG) pregnancy test (applies to female participants of childbearing potential only).
• Body mass index between 18 and 40 kg/m^2, inclusive.

Exclusion Criteria:

• Participants currently meeting DSM-IV-TR criteria for schizoaffective disorder, schizophreniform disorder, bipolar I and II and known or suspected borderline or antisocial personality disorder. or other DSM-IV-TR axis II disorders.
• Participants in their first episode of psychosis.
• Treatment-resistant schizophrenia over the last 2 years.
• Positive result from the blood alcohol test or from the urine drug screen for any prohibited medication.
• At imminent risk of injuring self or others or causing significant damage to property.
• Suicide risk.

There was no masking in the Open-Label Phase. There was masking in the Double-Blind Phase