A Study of Paliperidone Palmitate 3 Month Formulation for the Treatment of Patients With Schizophrenia

This is a randomized (the study drug is assigned by chance), double blind (neither physician
nor patient knows the treatment that the patient receives), parallel group (each group of
patients will be treated at the same time), placebo-controlled (an inactive substance is
compared with a drug to test whether the drug has a real effect in a clinical trial)
multicenter study. The study consists of 4 phases: a Screening Phase (up to 3 weeks); a
17-week flexible dose open-label Transition Phase (open-label phase means that all people
know the identity of the intervention); a 12-week fixed dose open-label Maintenance Phase;
and a randomized, double-blind, fixed dose, placebo-controlled relapse prevention phase
(referred to as the Double-blind Phase). Patients who meet specific stabilization criteria
will enter the Double-blind Phase at Week 29. Patients will be randomly assigned, in a 1:1
ratio, to receive either a fixed dose of PP3M or placebo. The Double-blind Phase will be of
variable duration; patients will remain in the study until they experience a relapse event
or meet discontinuation criteria.

Inclusion Criteria:

- Patients with schizophrenia for more than 1 year

- A total score in the Positive and Negative Syndrome Scale (PANSS) < 120

- Signed informed consent

- Women must not be pregnant, breastfeeding, and if capable of pregnancy must practice
an effective method of birth control

- Men must agree to use a double-barrier method of birth control

- Be medically stable on the basis of clinical laboratory tests, physical examination,
medical history, vital signs, and electrocardiogram (ECG) Exclusion Criteria:

- A diagnosis other than schizophrenia, e.g., dissociative disorder, bipolar disorder,
major depressive disorder, schizoaffective disorder, schizophreniform disorder,
autistic disorder, primary substance-induced psychotic disorder, dementia-related
psychosis

- Relevant history or current presence of any significant or unstable medical
condition(s) determined to be clinically significant by the Investigator (ie,
obesity, diabetes, heart disease etc)

- A diagnosis of substance dependence within 6 months before screening

- History of neuroleptic malignant syndrome (NMS) or tardive dyskinesia

- Clozapine use in the last 2 months when used for treatment-resistant or
treatment-refractory illness

- Clinically significant findings in biochemistry, hematology, ECG or urinalysis
results

- Any other disease or condition that, in the opinion of the investigator, would make
participation not in the best interest of the patient or that could prevent, limit,
or confound the protocol-specified assessments