All visits will be conducted on an outpatient basis. Visits for a given subject throughout the study should be scheduled to start at approximately the same time, in the morning. Subjects will be instructed to take their daily dose of study drug each morning (when not attending a study visit), at least 30 minutes before breakfast. Subjects will be instructed to not take study drug on the morning of each treatment period visit and to bring study drug supplies with them to the clinic; study drug will be administered in the clinic after all scheduled assessments/procedures (after all pre-dose assessments at each of the Day 1 and Week 12 Visits) are completed.