96-week results of a dual therapy with darunavir/ritonavir plus rilpivirine once a day vs triple therapy in patients with suppressed viraemia: virological success and non-HIV related morbidity evaluation.

Antiretroviral therapies have been tested with the goal of maintaining virological suppression with a particular attention in limiting drug-related toxicity. With this aim we designed the DUAL study: a randomized, open-label, multicenter, 96 weeks-long pilot exploratory study in virologically suppressed HIV-1+ patients with the aim of evaluating the immunovirological success and the impact on non-HIV related morbidity of switching to a dual therapy with darunavir-ritonavir (DRV/r) and rilpivirine (RPV). We recruited patients who received a PI/r-containing HAART for ≥6 months, HIV-RNA < 50 cp/mL for ≥3 months, eGFR > 60 mL/min/1,73m2, without DRV or RPV RAMs. We randomized patients in arm A: RPV + DRV/r QD or arm B: ongoing triple therapy. The primary endpoint has been defined as the percentage of patients with HIV-RNA < 50 cp/mL at week 48 (ITT). VACS index, Framingham CVD risk (FRS) and urinary RBP (uRBP) were calculated. We used Chi-square or Fisher statistics for categorical variables and Mann-Whitney U for continuous ones. Forty-one patients were enrolled (22 in arm A, 14 in arm B, plus 5 screening failures): 30 patients reached 96 weeks: 100% had HIV-RNA < 50 cp/mL in arm A versus 91.7% in arm B. Similar changes were observed in median CD4/mL between baseline and week 96 (+59 versus - 31, p: n.s.). Thirty-one in arm A and 23 in arm B adverse events took place, whereas only 1 was serious (arm A: turbinate hypertrophy, unrelated to HAART). Among the 6 discontinuations (3 in A, 3 in B), only 1 was related to adverse event (arm A: G3 depression, insomnia, weakness). VACS index, median FRS and median uRBP values did not vary from baseline to week 96. At 96-weeks all patients switched to a QD 2-drug regimen based on DRV/r + RPV maintained HIV-RNA suppression, but a single patient who showed a virological failure at week 4. CD4 counts increased overtime without significant differences between the two arms. The novel dual regimen was well tolerated with the same amount of discontinuation as the control arm. VACS index, FRS and uRBP did not differ between arms at week 96.

Clinical and genetic factors associated with increased risk of severe liver toxicity in a monocentric cohort of HIV positive patients receiving nevirapine-based antiretroviral therapy.

BACKGROUND: Nevirapine has been used as antiretroviral agent since early '90. Although nevirapine is not currently recommended in initial anti-HIV regimens, its use remains consistent in a certain number of HIV-1-positive subjects. Thus, our aim was to determine clinical and genetic factors involved in the development of severe nevirapine induced liver toxicity. METHODS: We retrospectively analyzed all HIV positive patients who were followed at the Infectious Diseases Unit, DIBIC Luigi Sacco, University of Milan from May 2011 to December 2015. All patients treated with nevirapine who underwent a genotyping for the functional variants mapping into ABCB1, CYP2B6, CYP3A4 and CYP3A5 genes were included in the analysis. Severe hepatotoxicity was defined as ACTG grade 3-4 AST/ALT increase during the first three months of nevirapine treatment. The causality assessment between NVP exposure and drug-induced liver injury was performed by using the updated Roussel Uclaf Causality Assessment Methods. Hardy Weinberg equilibrium was tested by χ2 test. A multivariable logistic regression model was constructed using a backward elimination method. RESULTS: Three hundred and sixty-two patients were included in the analysis, of which 8 (2.2%) experienced a severe liver toxicity. We observed no differences between patients with and without liver toxicity as regards gender, ethnicity, age and immune-virological status. A higher prevalence of HCV coinfection (75.0% vs 30.2%; p = .0013) and higher baseline AST (58 IU/L vs 26 IU/L; p = 0.041) and ALT (82 IU/L vs 27 IU/L; p = 0.047) median levels were observed in patients with liver toxicity vs those without toxicity. The genotypes CT/TT at ABCB1 rs1045642 single nucleotide polymorphism (SNP), showed a protective effect for liver toxicity when compared with genotype CC (OR = 0.18, 95%CI 0.04-0.76; p = 0.020) in univariate analysis. In the multivariate model, HCV coinfection was independently associated with higher risk of developing liver toxicity (aOR = 8.00, 95%CI 1.27-50.29; p = 0.027), whereas ABCB1 rs1045642 CT/TT genotypes (aOR = 0.10, 95%CI 0.02-0.47; p = 0.004) was associated with a lower risk. CONCLUSIONS: According to our findings HCV coinfection and ABCB1 rs1045642 SNP represent independent determinants of severe liver toxicity related to nevirapine. This genetic evaluation could be included as toxicity assessment in HIV-1-positive subjects treated with nevirapine.

Clinical and genetic determinants of nevirapine plasma trough concentration.

BACKGROUND: Only few data are available on the influence of CYP2B6 and CYP3A4/A5 polymorphisms on nevirapine plasma concentrations in the Caucasian population. Our aim was to assess the impact of CYP2B6 and CYP3A4/A5 polymorphisms on nevirapine plasma concentrations consecutively collected. METHODS: We retrospectively analyzed clinical data of all HIV-positive patients who were followed at the Infectious Diseases Unit, DIBIC Luigi Sacco, University of Milan between January 2000 and December 2015. All patients with at least one nevirapine plasma trough concentration (NVP Cmin) determination were tested for CYP2B6 c.516 G>T, CYP3A4*22C>T and CYP3A5*3 A>G polymorphisms. Univariate and multivariate regression analyses were carried out considering NVP Cmin as the dependent variable and genetic polymorphisms and clinical characteristics as independent variables. RESULTS: A total of 143 patients were evaluated. Most of them were males (61.5%) and Caucasian (92.3%). Overall, NVP Cmin varied from 1571 to 14,189 ng/mL (median = 5063 ng/mL, interquartile range = 3915-6854). The median NVP Cmin significantly differed in patients with different CYP2B6 genotypes, but did not vary in those with different CYP3A phenotypes. In the final general linear model, factors significantly associated with a higher NVP Cmin were each extra unit of T alleles of CYP2B6 rs3745274 (ß = 0.328, 95% confidence interval = 0.172-0.484; p < 0.0001), older age (ß = 0.362, 95% confidence interval = 0.193-0.532; p < 0.0001) and hepatitis C virus coinfection (ß = 0.161, 95% confidence interval = 0.006-0.315; p < 0.041). CONCLUSION: Our study, conducted in a prevalent Caucasian population, highlighted the importance of CYP2B6 genetic variants in influencing nevirapine plasma trough concentration. Furthermore, older age and hepatitis C virus coinfection significantly increase exposure to nevirapine.

Treatment outcome in HIV+ patients receiving 3- or 4-drug regimens during PHI.

INTRODUCTION: The optimal timing and modality of therapeutic intervention during early phases of HIV infection is still debated; in our prospective observational study we evaluated immunological and virological outcome in HIV+ patients treated during acute or recent HIV infection. MATERIALS AND METHODS: A total of 25 naïve patients with acute (detectable HIV-RNA, immature Western Blot) or recent (documented infection within six months) HIV infection were recruited at the Infectious Diseases Units of the University of Milan and Turin from 2009 to 2014. Patients received treatment with two NRTIs+one NNRTI/bPI, with or without an induction phase with an additional fourth drug (raltegravir or maraviroc) until HIV-RNA undetectability maintained for six months. Blood samples for HIV-RNA, lymphocyte subsets and tropism assessment were obtained at the beginning of the treatment (BL). Patients underwent subsequent six-monthly follow up for clinical outcome, CD4 cell count and HIV-RNA up to 18 months. RESULTS: Median increase in CD4 cells from 0 to 12 months was greater in patients treated during acute (n=18) versus recent (n=7) infection [284/µL, IQR (227-456) versus 176/µL, IQR (70-235); Mann-Whitney test, p=0.046]. This higher value was maintained through 18 months, although failing to reach statistical significance. Patients with acute or recent infection did not significantly differ in virological success (83.3% versus 85.7% at 12 months). We considered CD4 cells gains at six months (multivariate analysis, ANCOVA; Figure 1) and detected an inverse correlation with CD4 levels at BL (r=-0.517; p=0.008) and a direct correlation with the status of acute infection (r=0.234, p NS). This last correlation reached statistical significance at 12 months (r=0.418, p=0.035), whereas the inverse correlation with CD4 levels at BL was still present without a statistical significance (r=-0.350; p=0.072). Patients treated with three or four drugs did not show any significant difference in immunological nor virological response (Mann-Whitney and χ(2) test). Modification or interruption of therapy for tolerability took place in 4 out of 25 patients, all while receiving four drugs; two patients underwent STI between 12 and 18 months following virological success. CONCLUSIONS: Treatment of primary infection appeared to be effective in preserving the pool of CD4 cells in acute more than recent infection. There was no evidence of a different outcome through the addition of a fourth drug to the standard treatment.