Mutations in hepatitis C virus NS3 protease domain associated with resistance to specific protease inhibitors in antiviral therapy naïve patients

The prevalence of naturally occurring mutations in hepatitis C virus associated with resistance to protease inhibitors in chronically infected patients has not been reported in Brazil. The NS3 serine protease domain was sequenced in 114 therapy-naïve patients infected with subtype 1a (n = 48), 1b (n = 53), or 3a (n = 13). A V36L mutation was observed in 5.6% patients infected with subtype 1b and in all isolates of the 3a subtype, and a T54S mutation was detected in 4.1% of isolates of subtype 1a. In conclusion, the presence of variants carrying mutations associated with resistance to protease inhibitors in therapy-naïve patients may be important for future therapeutic strategies.     

Influence of HIV-1 V2 sequence variability on bacterial translocation in antiretroviral naïve HIV-1 infected patients

HIV-1 V2 domain binds α4β7, which assists lymphocyte homing to gut-associated lymphoid tissue. This triggers bacterial translocation, thus contributing to immune activation. We investigated whether variability of V2 ^179-181binding site could influence plasma levels of lipopolysaccharide (LPS) and soluble cluster of differentiation 14 (sCD14), markers of microbial translocation/immune activation. HIV gp120 sequences from antiretroviral naïve patients were analyzed for V2 tripeptide composition, length, net charge, and potential N-linked-glycosylation sites. LPS and sCD14 plasma levels were quantified. Clinical/immuno-virologic data were retrieved. Overall, 174 subjects were enrolled, 8% with acute infection, 71% harboring a subtype B. LDV^179-181 was detected in 41% and LDI in 27%. No difference was observed between levels of LPS or sCD14 according to different mimotopes or according to other sequence characteristics. By multivariable analysis, only acute infection was significantly associated with higher sCD14 levels. In conclusion, no association was observed between V2 tripeptide composition and extent of bacterial translocation/immune activation.     

Characterization of drug resistance mutations in naïve and ART-treated patients infected with HIV-1 in Yaounde, Cameroon

Currently the prevalence of HIV‐1 infection in Cameroon is 5.1%, CRF02_AG subtype is responsible for about 50% of infections. Since an HIV‐1 drug resistance test is not yet available widely, accurate data on the prevalence of resistant viral strains are missing. The objective of this study was to determine HIV‐1 genetic diversity and to characterize HIV‐1 mutations conferring drug resistance among antiretroviral therapy (ART)‐naïve and ART‐treated patients. A cohort of 239 patients infected with HIV were followed‐up between January 2007 and July 2010 in Cameroon. Two hundred and sixteen plasma samples were sequenced for phylogenetic analysis and identification of drug resistance mutations in the HIV‐1 pol region. A significant genetic diversity was found: Seven pure subtypes (A1, A3, D, F1, F2, G, H), nine circulating recombinant forms (CRFs: 01_AE, 02_AG, 06cpx, 09cpx, 11cpx, 13cpx, 16cpx, 18cpx, 37cpx) and one new unique recombinant form (URF) (G/F2). The rate of transmitted drug resistance (TDR) in naïve patients was 8.2% (4/49). Around 80% of patients failing a first‐line ART harbored a virus with at least one resistance mutation to two antiretroviral (ARV) classes, and 36% of those failing a second‐line regimen carried a virus with at least one resistant mutation to three ARV classes. The high level of drug resistance observed in the cohort is alarming because this occurred as a result of only few years of treatment. Adherence to therapy, adequate education of physicians, and the appropriate use of genotypic resistance assay are critical points of intervention for the improvement of patient care. J. Med. Virol. 84:721–727, 2012. © 2012 Wiley Periodicals, Inc.     

HIV-1 integrase inhibitor resistance among treatment naïve patients in the West of Scotland

BackgroundTransmitted integrase inhibitor resistance is rare, with only a small number of cases reported world-wide to date.ObjectivesThe aim of this study was to assess whether transmitted integrase inhibitor resistance has occurred in Scotland and if so, could there be a case for performing genotypic integrase resistance testing at baseline.Study designThe study population consisted of 106 treatment naïve, newly diagnosed, HIV positive patients. The patient samples were collected between October 2015 and March 2016 at the time of HIV diagnosis and prior to initiation of anti-retroviral therapy. The integrase region was amplified and sequenced.ResultsWe detected integrase inhibitor resistance (T66I/T) at baseline in one patient sample. This is a non-polymorphic mutation seen in patients receiving elvitegravir which confers high-level resistance to elvitegravir and intermediate resistance to raltegravir. A further 10 patients had accessory mutations which have minimal or no effect on susceptibility to integrase inhibitors.ConclusionsTransmitted integrase inhibitor resistance remains rare. The results of the present study do not support performing integrase resistance testing at baseline.     

Prevalence of HIV-1 integrase mutations related to resistance to dolutegravir in raltegravir naïve and pretreated patients

The prevalence of HIV-1 integrase mutations related to resistance to the next-generation integrase inhibitor (INI), dolutegravir (DTG), was assessed in 440 INI-naïve subjects and in 120 patients failing a raltegravir (RTG)-containing regimen. Of the mutations selected by DTG in vitro, S153FY was not detected in any isolate while L101I and T124A were highly prevalent in both groups and significantly associated with non-B subtype. RTG-selected double and triple mutants, mostly the G140S/Q148H variant, were detected in only 32 (26.7%) RTG-treated patients. As L101I and T124A do not appear to exert any major effect in vivo and double and triple mutants resistant to DTG are infrequently selected by RTG, DTG can be effectively used in INI-naïve patients and may retain activity in many patients failing RTG.     

High rates of transmitted drug resistance among newly-diagnosed antiretroviral naïve HIV patients in Northern Greece,data from 2009–2011

We conducted a retrospective study on the prevalence and correlates of transmitted drug resistance among newly-diagnosed antiretroviral naive human immunodeficiency virus (HIV) patients in Northern Greece, during the period 2009–11. Transmitted drug resistance was documented in 21.8% of patients enrolled, affecting approximately 40% of subtype A HIV-1-infected individuals. Overcoming challenges due to the ongoing financial crisis, effective preventive measures should be implemented to control further dissemination of resistant HIV strains.     

Immunological and virological changes in antiretroviral naïve human immunodeficiency virus infected patients randomized to G-CSF or placebo simultaneously with initiation of HAART

To determine the efficacy of combined G-CSF and highly active antiretroviral treatment (HAART), a randomized, double blind, placebo controlled study was conducted. Treatment naive human immunodeficiency virus (HIV) infected patients were randomized to receive either placebo or G-CSF (0.3 mg/ml, 3 times a week) for 12 weeks and HAART simultaneously. The trial was terminated prematurely after interim analysis performed because of a case of severe encephalopathia in the G-CSF group. At that point 11 HIV infected patients with a CD4+ T cell count < 350/mm3 had been randomized to the G-CSF group (n = 6) or placebo group (n = 5). In both groups plasma HIV RNA decreased significantly in response to HAART. However, plasma HIV RNA changed significantly different between the two groups with the decrease being less pronounced in the G-CSF group (P = 0.02). The concentrations of CD4+ memory T cells and CD8+ naive and memory T cells increased in response to HAART, and there was a trend towards more pronounced increases in several T-cell subpopulations in the G-CSF group. The CD56+ NK cells increased significantly more in the G-CSF group compared with placebo (P = 0. 000). All patients in the G-CSF group reported bone pain. The present data do not support simultaneous administration of G-CSF with initiation of HAART in treatment naive HIV infected patients.     

Inflammatory effects of atazanavir/ritonavir versus darunavir/ritonavir in treatment naïve,HIV-1-infected patients

Background: Limited studies have compared the impact of different antiretroviral regimens on soluble markers of inflammation with discordant results.

Methods: In this prospective study, treatment naïve HIV-1-infected patients were included if they started their current regimen with atazanavir/ritonavir (ATV/r) (N = 73, Group 1) or darunavir/ritonavir (DRV/r) (N = 85, Group 2) plus tenofovir/emtricitabine. The analysis of IL-6, MCP-1, sCD163, VCAM-1, ox-LDL, and adiponectine was performed on two stored plasma samples, the first prior to antiretroviral therapy initiation and the second one year after initiation.

Results: The results of our analysis show a difference in ox-LDL between the two groups with higher mean (SD) values in ATV/r based group 608.5 ± 137.4 versus 519.1 ± 119.6 in DRV/r group, after controlling for baseline levels of ox-LDL as well as other potential confounding factors controlled by means of matching design or linear regression modelling.

Conclusions: Our analysis provides further data examining the association between the modulation of vascular inflammatory and of activation markers with specific protease inhibitors-based treatments over one year of exposure to these drugs. The data show little evidence for an association, supporting the notion that antiretroviral regimens has generally poor efficiency in downregulating these soluble markers.     

Prevalence and impact of hepatitis B and C virus co-infections in antiretroviral treatment naïve patients with HIV infection at a major treatment center in Ghana

Data on the effects of the presence of hepatitis B virus (HBV) and hepatitis C virus (HCV) in patients co‐infected with these viruses and HIV in West Africa are conflicting and little information is available in Ghana. A cohort of 138 treatment naïve individuals infected with HIV was screened for HBV and HCV serologic markers; HBsAg positive patients were tested for HBeAg, anti‐HBe, and anti‐HBc IgM. The viral load of HIV‐1 in the plasma was determined in 81 patients. Eighteen of the 138 patients (13%) and 5 (3.6%) had HBsAg and anti‐HCV, respectively. None of the patients had anti‐HBc IgM, but 10 (55.6%) and 8 (44.4%) of the 18 patients who were HBsAg positive had HBeAg and anti‐HBe, respectively. In patients with measurement of CD4⁺ undertaken within 1 month (n = 83), CD4⁺ count was significantly lower in patients with HBeAg (median [IQR], 81 [22–144]) as compared to those with anti‐HBe (median [IQR], 210 [197–222]) (P = 0.002, CI: ?96.46 to 51.21). However, those with HIV mono‐infection had similar CD4⁺ counts (median [IQR], 57 [14–159]) compared to those with HBeAg (P = 1.0, CI: ?71.75 to 73.66). Similar results were obtained if CD4⁺ count was measured within 2 months prior to initiation of HAART (n = 119). Generally, HBV and anti‐HCV did not affect CD4⁺ and viral loads of HIV‐1 in plasma but patients with HIV and HBV co‐infection who had HBeAg had more severe immune suppression as compared to those with anti‐HBe. This may have implication for initiating HAART in HBV endemic areas. J. Med. Virol. 84:6–10, 2011. © 2011 Wiley Periodicals, Inc.     

Rare emergence of drug resistance in HIV-1 treatment -naïve patients after 48 weeks of treatment with elvitegravir/cobicistat/emtricitabine/tenofovir alafenamide

Tenofovir alafenamide (TAF), a novel prodrug of the NtRTI tenofovir (TFV), delivers TFV-diphosphate (TFV-DP) to target cells more efficiently than the current prodrug, tenofovir disoproxil fumarate (TDF), with a 90% reduction in TFV plasma exposure. TAF, within the fixed dose combination of elvitegravir /cobicistat / emtricitabine (FTC)/TAF (E/C/F/TAF), has been evaluated in one Phase 2 and two Phase 3 randomized, double-blinded studies in HIV-infected treatment-naive patients, comparing E/C/F/TAF to E/C/F/TDF. In these studies, the TAF-containing group demonstrated non-inferior efficacy to the TDF-containing comparator group with 91.9% of E/C/F/TAF patients having <50 copies/mL of HIV-1 RNA at week 48. An integrated resistance analysis across these three studies was conducted, including HIV-1 genotypic analysis at screening, and genotypic/phenotypic analysis for patients with HIV-1 RNA >400 copies/mL at virologic failure. Pre-existing primary resistance-associated mutations (RAMs) were observed at screening among the 1903 randomized and treated patients: 7.5% had NRTI-RAMs, 18.2% had NNRTI-RAMs, and 3.4% had primary PI-RAMs. Pre-treatment RAMs did not influence treatment response at Week 48. In the E/C/F/TAF group, resistance development was rare; seven patients (0.7%, 7/978) developed NRTI-RAMs, five of whom (0.5%, 5/978) also developed primary INSTI-RAMs. In the E/C/F/TDF group, resistance development was also rare; seven patients (0.8%, 7/925) developed NRTI-RAMs, four of whom (0.4%, 4/925) also developed primary INSTI-RAMs. An additional analysis by deep sequencing in virologic failures revealed minimal differences compared to population sequencing. Overall, resistance development was rare in E/C/F/TAF-treated patients, and the pattern of emergent mutations was similar to E/C/F/TDF.