Efficacy and safety of once-daily darunavir/ritonavir versus lopinavir/ritonavir in treatment-naive HIV-1-infected patients at week 48

Background: The present primary analysis of AntiRetroviral Therapy with TMC114 ExaMined In naive Subjects (ARTEMIS) compares the efficacy and safety of once-daily darunavir/ritonavir (DRV/r) with that of lopinavir/ritonavir (LPV/r) in treatment-naive patients. Methods: Patients with HIV-1 RNA at least 5000 copies/ml were stratified by HIV-1 RNA and CD4 cell count in a phase III, open-label trial, and randomized to receive DRV/r 800/100 mg qd or LPV/r 800/200 mg total daily dose (bid or qd) plus fixed-dose tenofovir and emtricitabine for 192 weeks. The primary objective was to demonstrate non-inferiority of DRV/r as compared with LPV/r in HIV-1 RNA less than 50 copies/ml per-protocol time-to-loss of virologic response at 48 weeks. Results: Six hundred and eighty-nine patients were randomized and treated; mean baseline HIV-1 RNA: 4.85 log10 copies/ml and median CD4 count: 225 cells/μl. At 48 weeks, 84% of DRV/r and 78% of LPV/r patients achieved HIV-1 RNA less than 50 copies/ml (estimated difference = 5.6 [95% confidence interval -0.1-11]%), demonstrating non-inferiority of DRV/r as compared with LPV/r (P < 0.001; per-protocol time-to-loss of virologic response). Patients with HIV-1 RNA at least 100 000 copies/ml had a significantly higher response rate with DRV/r (79%) versus LPV/r (67%; P < 0.05). Median CD4 cell count increases (non-completer = failure; cells/μl) were 137 for DRV/r and 141 for LPV/r. DRV/r had a lower incidence of possibly treatment-related grade 2-4 gastrointestinal-related adverse events (7 versus 14%) and treatment-related moderate-to-severe diarrhea (4 versus 10%) than LPV/r. Adverse events leading to discontinuation were DRV/r: 3% and LPV/r: 7%. Conclusion: DRV/r 800/100 mg qd was non-inferior to LPV/r 800/200 mg at 48 weeks, with a more favorable safety profile. Significantly higher response rates were observed with DRV/r in patients with HIV-1 RNA at least 100 000 copies/ml. DRV/r 800/100 mg offers a new effective and well tolerated once-daily, first-line treatment option for treatment-naive patients. © 2008 Wolters Kluwer Health / Lippincott Williams & Wilkins.