Efficacy and safety of darunavir/ritonavir in treatment-experienced HIV type-1 patients in the POWER 1, 2 and 3 trials at week 96

Background: Long‐term (96‐week) efficacy and safety of the protease inhibitor (PI) darunavir coadministered with low‐dose ritonavir (DRV/r) was evaluated in HIV type‐1 (HIV‐1)‐infected patients with extensive prior treatment experience in the POWER 1, 2 and 3 trials. Methods: Patients with HIV‐1 RNA>1,000 copies/ml and >1 primary PI mutation were randomized to receive either DRV/r 600/100 mg twice daily plus an optimized background regimen (OBR), or an investigator‐selected control PI (CPI) plus OBR (POWER 3 was a DRV/r 600/100 mg twice daily single‐arm study). The proportion of patients with HIV‐1 RNA<50 copies/ml at week 96 was assessed (intent‐to‐treat [ITT], time‐to‐loss of virological response algorithm). Results: In total, 467 patients received DRV/r 600/100 mg twice daily; 124 patients received CPI(s). At week 96, 39% of DRV/r patients in POWER 1 and 2 (pooled analysis) versus 9% of CPI patients achieved HIV‐1 RNA<50 copies/ ml (ITT, time‐to‐loss of virological response algorithm; P<0.001). A similar proportion of DRV/r patients (42%) in POWER 3 achieved HIV‐1 RNA<50 copies/ml at week 96. Mean absolute CD4+ T‐cell count increase for DRV/r at 96 weeks was 133 cells/mm3 in POWER 1 and 2 and 103 cells/mm3 in POWER 3. Grade 2‐4 treatmentemergent adverse events at least possibly related to DRV/r (>2% incidence, excluding laboratory abnormalities) were diarrhoea (3%), vomiting (3%), nausea (2%) and headache (2%). Conclusions: Treatment with DRV/r 600/100 mg twice daily was well tolerated and led to sustained virological and immunological responses in treatment‐experienced HIV‐1‐infected patients over 96 weeks. 2009 International Medical Press.