A Study of QT and QTc Intervals in Patients Administered Immediate Release Paliperidone

This is a multicenter, placebo- and positive-controlled, randomized study consisting of 3 periods: a screening period of up to 14 days (including a 5-day washout period), a double-blind period of 10 days (including the treatment phase \[Days 1 to 8\] and the posttreatment phase \[Days 9 and 10\]), and an end-of-study evaluation. Eligible patients will be randomly assigned to treatment with either paliperidone or moxifloxacin. Patients randomly assigned to receive paliperidone will receive placebo on Day 1, paliperidone 4 mg on Day 2, paliperidone 6 mg on Day 3, and paliperidone 8 mg on Days 4 through 8. Patients assigned to receive moxifloxacin will receive placebo on Days 1 through 7 and moxifloxacin 400 mg on Day 8. The moxifloxacin treatment group will provide a concurrent active control to confirm that the study is adequate to detect a drug effect (i.e., assay sensitivity) on QTc interval. Baseline ECGs will be recorded on the last day of the washout period (Day 1). Serial time matched 12 lead ECG triplicate readings will be recorded on Days 1, 2, 3, 4, 5 (predose), 8, 9, and 10. This study is being conducted to thoroughly assess potential QT/QTc interval changes following administration of paliperidone. The results from this safety study, along with the ECG results from all paliperidone clinical studies, will be used in the evaluation of the cardiovascular safety of paliperidone. Paliperidone IR orally once daily: 4 mg on Day 2, 6 mg on Day 3, and 8 mg on Days 4 through 8; Active control: a single oral dose of moxifloxacin 400 mg on Day 8