Subjects will have in-clinic assessments on 12 days to obtain 24-hour PK and PD data. Subjects will visit the clinic from the afternoon of Day -1 through the morning of Day 1. They will return at the end of each dosing period for a similar inpatient period (ie, from the afternoon of Day 6 through the morning of Day 8, from the afternoon of Day 13 through the morning of Day 15, from the afternoon of Day 20 through the morning of Day 22). Except for the first dose of each period and the doses taken in the clinic on the last day of each regimen and the afternoon of Days 6, 13 and 20, all other doses will be taken by the subject as an outpatient.