There are two parts to this study. Part A is a three-period, crossover design. Eligible subjects will be randomized to 1 of 4 sequences, in groups of 4 subjects each. All study drug doses, including the comparator, Reyataz, will be administered as single, open-labeled doses to subjects after a light meal. There will be a 7-day washout between individual subjects doses; that is, dosing will occur on the same day each week.