Of the patients with HIV-1 RNA < 50 copies/mL at week 48, a higher percentage of DRV/r patients than LPV/r patients remained with undetectable viral load (HIV-1 RNA < 50 copies/mL) at week 192. The findings of the week 192 analysis also extend earlier

findings from ARTEMIS in that the development of resistance is rare in treatment-naïve patients experiencing VF [8]. Only a few patients developed PI RAMs and none of these RAMs were major PI mutations. A low level of NRTI resistance developed in patients who failed virologically in both treatment groups. Furthermore, no loss of phenotypic susceptibility was observed for most PIs, thus confirming the preservation of PI susceptibility in ARTEMIS patients with VF. There was a lower incidence of discontinuations because of AEs in the DRV/r vs. LPV/r arm; these findings are consistent with the two find more previous analyses (at week 48 and week 96) [6, 7]. A lower incidence

of treatment-related grade 2–4 gastrointestinal AEs was also observed with DRV/r than with LPV/r, including a lower incidence of grade 2–4 diarrhoea, which was observed significantly less frequently with DRV/r than with LPV/r, thus confirming the long-term favourable gastrointestinal safety profile of DRV/r. A possible confounder of the tolerability findings is that a bioequivalence study of the LPV/r capsule and tablet, involving 15 healthy adults, showed that the tablet formulation exhibited slightly higher bioavailability PD0325901 in vitro and tended to result in a lower incidence of gastrointestinal AEs compared with the capsule [14]. In our study, patients in the DRV/r arm

had a lower incidence of grade 2–4 increases in triglycerides and total cholesterol than those in the LPV/r arm. Changes in LDL and HDL cholesterol, however, were similar for the two treatment groups. Other studies have also shown DRV/r to have a favourable lipid profile [4, 5, 15, 16], including studies in which patients switched from initial regimens with other PIs to DRV/r [17, 18]. This trial was open-label with both patients and physicians aware of the allocated treatment. It is possible GNA12 that an expectation of a lower rate of AEs with DRV/r may have influenced the duration of staying on medication and, therefore, there is always some possibility that a double-blind study may have shown different results with respect to rates of discontinuation. In the ARTEMIS study, the analysis carried out at week 48 showed DRV/r 800/100 mg once daily to have potential for use as a first-line once-daily treatment option for treatment-naïve HIV-1-infected adults. This final 192-week analysis demonstrates that DRV/r has an efficacy, resistance and safety profile favourable for long-term use. The authors would like to thank the patients and their families for their participation and support during the study.