Dual therapy with darunavir/r plus etravirine is safe and effective as switching therapy in antiretroviral experienced HIV‐patients. The BITER Study

Switching therapy studies are usually designed as second‐line antiretroviral treatment (ART) in patients without previous virologic failures. Combined ART (cART) with DRV/r and ETR has a good pharmacokinetic profile, high genetic barrier and has been proved as rescue therapy. The aim of our study was to analyze efficacy and safety of therapy with DRV/r plus ETR in treatment experienced HIV‐patients with previous therapeutic failures that need to switch ART. We present results at first 24 weeks. Methods Multicentre retrospective observational study. Inclusion criteria: adult HIV‐patients on ART with HIV‐VL <1000 cop/mL who started their ART with DRV/r (600/100 bid or 800/100 qd)+ETR by adverse events, non‐adherence, tolerability or prevention of future complications. Patients with acute AIDS events, HBV, pregnancy, drug addiction or previous selected mutations to DRV or ETR were excluded. Results Ninety‐nine patients were included, mean age: 47 years (r: 22–79); 70% men, 40.4% previous AIDS event and 39.3% HCV. Ninety‐one patients had received ≥3 cART regimens and 45≥5, 75 patients had HIV‐VL <50 cop/mL and 24 low‐level viremia (LLV): 297.5±261.4 cop/mL, CD4+ 568±279 cells/µL. ART before switching: NRTI+PI/r (33%), NNRTI (17%), PI/r+NNRTI (23%), PI/r+INI (13%), other (14%). Main reason to switching was: toxicity/intolerance 50 patients (renal 32%, gastrointestinal: 14%, hyperlipidaemia 10%; osteopenia/osteoporosis: 6%); improving adherence 26 patients; prevention of complications 19 patients. Nine subjects withdrew ART during follow‐up because: intolerance or new toxicity three; non‐adherence two; simplification to DRV/r monotherapy two; persistence of previous toxicity one; virologic failure one. At week 24, among patients who continued with DRV/r+ETR (n=90): 81 (89%) had VL<50 cop/mL, in those with with HIV‐VL<50 at baseline (67/90), 94% persisted with <50 cop., and in those with LLV (24/90), 61% (n=14) achieved a VL<50 cop. We didn't observe any significant difference in lab parameters between baseline and week 24. Estimated glomerular filtrate rate increased from 83.4±24.7 to 88.5±56.8 mL/min, p=NS. Regarding reason to switching, it improved in 42 cases, no changes: 20 cases; worsened: 4 cases, and non‐applicable or unknown: 24 cases. Conclusions Switching to dual therapy with DRV/r+ETR is an effective strategy in selected heavily experienced ART patients, even in those with LLV (<1000 cop/mL). This cART is safe and well tolerated, can reduce number of pills and improve adherence.