Patients in Arm B will have a series of blood draws over a 12-hour period in the clinic, around 14 days after starting the study, to find out if their LPV level needs to be increased. If the LPV level needs to be raised, an additional capsule of ritonavir will be added to the regimen to boost the level of LPV. Patients who had their ritonavir dose adjusted will return to have another 12-hour blood draw around Week 5. If the LPV level still needs to be changed, an additional capsule of LPV/r will be added to the regimen. A third 12-hour blood draw will be performed around Week 8 if a second dose adjustment was necessary.