Background Use evaluation in clinical practice of darunavir boosted with ritonavir(DRV/r) in HIV patients.

Purpose Study the effectiveness and safety of DRV/r at 24 weeks (24Ws).

Materials and methods Retrospective observational study of series of HIV patients treated with DRV/r between January-2008 and September-2011. The changes in viral load (VL) and CD4 cell counts were evaluated in patients at baseline and at 24Ws. Also, safety and tolerability. End points: i)Primary effectiveness: % patients with VL<50 copies/ml at 24Ws, in patients with virologic failure(VF) or VL<50 initially; ii)Security: discontinuation rate due to intolerance or toxicity. Secondary effectiveness end points: i)Increased CD4 at 24w; ii)Security: hepatotoxicity(criteria: ALT/AST concentrations(U/L)>5N(55/41) in HCV/HBV non-coinfected and >3.5 baseline in coinfected). Data analysis using descriptive statistics

Results Most common DRV/r-based regimens: 27.3% PI/r, 54.5% PI/r+2NRTIs in VL<50 group and 35.3% PI/r+RAL+NNRTIs, 29.4% PI/r in VF group. 39.3% HCV/HBV coinfected(Child-Pugh A 90.9% and B 9.1%), none antihepatitis treatment, median ALT=125(IQR: 48-170)/AST=113(IQR: 55-136). Non-coinfected, median ALT=20(IQR: 12-24)/AST=20(IQR: 17.5-24.5). Two patients 18.2%(95% CI:2.3-51.7) with VL>50(94/113 copies/ml respectively) in VL<50 group, while 47%(95% CI:23-72.2) in VF group achieved undetectable VL. Median CD4 variation in VL<50 group was -16cell/mm³(95% CI: -88-102) and in VF group was 50 cell/mm³(95% CI: 33-179). 6.6%(n=30) patients discontinued treatment (abdominal pain/constipation and hypersensitivity). No episodes of hepatotoxicity.

Conclusions This study, performed in a small group of patients in routine clinical care, showed that, at 24Ws, the regimens of rescue which contain DRV/r, achieve similar rates of virological suppression than those observed in the clinical trials. During the study, DRV/r was well tolerated and safe in HIV non-coinfected and coinfected patients with mild and moderate hepatic impairment.