IndinavirHIV Protease InhibitorsRitonavirSaquinavirDrug TherapyNelfinavirDrug Therapy, CombinationAnti-HIV AgentsHIV InfectionsStavudineOxazinesHIV ProteaseDrug InteractionsLamivudineZidovudineHIV-1Area Under CurveBenzoxazinesPyrimidinonesCytochrome P-450 CYP3ACarbamatesReverse Transcriptase InhibitorsPyuriaLopinavirSophoraCD4 Lymphocyte CountDrug MonitoringViral LoadDidanosine