Prevalence of resistance mutations related to integrase inhibitor S/GSK1349572 in HIV-1 subtype B raltegravir-naive and -treated patients

Objectives To compare the frequency of previously in vitro-selected integrase mutations (T124A, T124A/S153F, S153Y, T124A/S153Y and L101I/T124A/S153Y) conferring resistance to S/GSK1349572 between HIV-1 subtype B integrase inhibitor (INI)-naive and raltegravir-treated patients. Methods Integrase sequences from 650 INI-naive patients and 84 raltegravir-treated patients were analysed. Results The T124A mutation alone and the combination T124A/L101I were more frequent in raltegravir-failing patients than in INI-naive patients (39.3% versus 24.5%, respectively, P = 0.005 for T124A and 20.2% versus 10.0%, respectively, P = 0.008 for T124A/L101I). The S153Y/F mutations were not detected in any integrase sequence (except for S153F alone, only detected in one INI-naive patient). Conclusions T124A and T124A/L101I, more frequent in raltegravir-treated patients, could have some effect on raltegravir response and their presence could play a role in the selection of other mutations conferring S/GSK1349572 resistance. The impact of raltegravir-mediated changes such as these on the virological response to S/GSK1349572 should be studied further

Antiretroviral-naive and -treated HIV-1 patients can harbour more resistant viruses in CSF than in plasma

Objectives The neurological disorders in HIV-1-infected patients remain prevalent. The HIV-1 resistance in plasma and CSF was compared in patients with neurological disorders in a multicentre study. Methods Blood and CSF samples were collected at time of neurological disorders for 244 patients. The viral loads were >50 copies/mL in both compartments and bulk genotypic tests were realized. Results On 244 patients, 89 and 155 were antiretroviral (ARV) naive and ARV treated, respectively. In ARV-naive patients, detection of mutations in CSF and not in plasma were reported for the reverse transcriptase (RT) gene in 2/89 patients (2.2%) and for the protease gene in 1/89 patients (1.1%). In ARV-treated patients, 19/152 (12.5%) patients had HIV-1 mutations only in the CSF for the RT gene and 30/151 (19.8%) for the protease gene. Two mutations appeared statistically more prevalent in the CSF than in plasma: M41L (P = 0.0455) and T215Y (P = 0.0455). Conclusions In most cases, resistance mutations were present and similar in both studied compartments. However, in 3.4% of ARV-naive and 8.8% of ARV-treated patients, the virus was more resistant in CSF than in plasma. These results support the need for genotypic resistance testing when lumbar puncture is performe

Pitfalls of HIV genotypic tropism testing after treatment interruption

Item does not contain fulltextOBJECTIVES: The genotypic method is reliable enough for the determination of tropism and largely preferred in Europe. However, careful interpretation is essential when assessing HIV genotypic resistance during treatment interruption (TI) due to the possible disappearance of resistant strains. The results of HIV genotypic tropism testing in such a context remain unknown. METHODS: First, we studied changes in tropism in patients included in a structured TI assay: the Reverse study. Second, we investigated the unexpected tropism switches from X4 to R5 recorded in our routine database. RESULTS: Tropism determination was possible in 21 patients of the Reverse study, 9 of whom had an X4 virus (43%) at baseline. Two patients displayed a change of tropism during TI, both switching from X4 to R5. Regarding the database investigation, 7 of the 222 patients with at least two plasma tropism determinations recorded in the database displayed a switch from X4 to R5. TI due to non-compliance at the time of the tropism change was reported for five of these seven patients. CONCLUSIONS: We have shown that the redistribution of the HIV population caused by TI could potentially result in X4 viruses becoming undetected and inappropriate prescription of a CCR5 receptor antagonist. Therefore, genotypic tropism results should be interpreted with caution in such a context

International Cohort Analysis of the Antiviral Activities of Zidovudine and Tenofovir in the Presence of the K65R Mutation in Reverse Transcriptase▿

A K65R mutation in HIV-1 reverse transcriptase can occur with the failure of tenofovir-, didanosine-, abacavir-, and, in some cases, stavudine-containing regimens and leads to reduced phenotypic susceptibility to these drugs and hypersusceptibility to zidovudine, but its clinical impact is poorly described. We identified isolates with the K65R mutation within the Stanford Resistance Database and a French cohort for which subsequent treatment and virological response data were available. The partial genotypic susceptibility score (pGSS) was defined as the genotypic susceptibility score (GSS) excluding the salvage regimen's nucleoside reverse transcriptase inhibitor (NRTI) component. A three-part virologic response variable was defined (e.g., complete virologic response, partial virologic response, and no virologic response). Univariate, multivariate, and bootstrap analyses evaluated factors associated with the virologic response, focusing on the contributions of zidovudine and tenofovir. Seventy-one of 130 patients (55%) achieved a complete virologic response (defined as an HIV RNA level of <200 copies/ml). In univariate analyses, pGSS and zidovudine use in the salvage regimen were predictors of the virologic response. In a multivariate analysis, pGSS and zidovudine and tenofovir use were associated with the virologic response. Bootstrap analyses showed similar reductions in HIV RNA levels with zidovudine or tenofovir use (0.5 to 0.9 log10). In the presence of K65R, zidovudine and tenofovir are associated with similar reductions in HIV RNA levels. Given its tolerability, tenofovir may be the preferred agent over zidovudine even in the presence of the K65R mutation

Characterizing the emergence and persistence of drug resistant mutations in HIV-1 subtype C infections using 454 ultra deep pyrosequencing.

BACKGROUND: The role of HIV-1 RNA in the emergence of resistance to antiretroviral therapies (ARTs) is well documented while less is known about the role of historical viruses stored in the proviral DNA. The primary focus of this work was to characterize the genetic diversity and evolution of HIV drug resistant variants in an individual's provirus during antiretroviral therapy using next generation sequencing. METHODS: Blood samples were collected prior to antiretroviral therapy exposure and during the course of treatment from five patients in whom drug resistance mutations had previously been identified using consensus sequencing. The spectrum of viral variants present in the provirus at each sampling time-point were characterized using 454 pyrosequencing from multiple combined PCR products. The prevalence of viral variants containing drug resistant mutations (DRMs) was characterized at each time-point. RESULTS: Low abundance drug resistant viruses were identified in 14 of 15 sampling time-points from the five patients. In all individuals DRMs against current therapy were identified at one or more of the sampling time-points. In two of the five individuals studied these DRMs were present prior to treatment exposure and were present at high prevalence within the amplified and sequenced viral population. DRMs to drugs other than those being currently used were identified in four of the five individuals. CONCLUSION: The presence of DRMs in the provirus, regardless of their observed prevalence did not appear to have an effect on clinical outcomes in the short term suggesting that the drug resistant viral variants present in the proviral DNA do not appear to play a role in the short term in facilitating the emergence of drug resistance

Persistent Low-Level Viraemia in Antiretroviral Treatment-Experienced Patients Is Not Linked to Viral Resistance or Inadequate Drug Concentrations

Abstract Objectives To assess genotypic sensitivity scores (GSSs), plasma antiretroviral concentrations (PACs) and immunovirological outcomes at Week 96 (W96) in patients with persistent low-level viraemia (LLV). Methods On 1 January 2017, we analysed data from patients on three-drug regimens with persistent LLV defined as at least two consecutive plasma viral loads (pVLs) between 21 and 200\,copies/mL (including one pVL of ≥q50\,copies/mL), at the Pitié-Salpêtrière Hospital. Outcomes were: GSS, PACs and HIV-DNA load at study entry; and virological status and proportion of patients with resistance-associated mutations (RAMs) at W96. Results Fifty-seven patients were included, with median age of 52.6\,years (IQR 45.2\textendash 57.9), last CD4 count of 658\,cells/mm3 (IQR 462\textendash 909) and total ART duration of 10.2\,years (IQR 5.7\textendash 15.2). LLV duration was 14.0\,months (IQR 5.5\textendash 22.3). GSS was 3 in 46/57 (81%) patients and PACs were adequate in 53/57 (93%) patients. Median total HIV-DNA was 2.65\,log10\,copies/106\,cells (IQR 2.44\textendash 2.86). During follow-up, 26/57 (46%) had experienced ART modifications. At W96, 38/57 (67%) patients remained with LLV, 15/60 (26%) had achieved confirmed pVL of &lt;20\,copies/mL and 4/57 (7%) had virological failure. The four virological failures were due to three ART interruptions and one incomplete adherence (selection of Y181C RAM). No factors (patient characteristics at study entry, GSS, PACs, total HIV-DNA load and ART modification) were associated with W96 viral outcome, except for time from HIV diagnosis and the LLV duration at study entry. Conclusions A substantial number of patients harbouring LLV had no resistance to ART and adequate PACs. Two-thirds of these patients remained with this LLV status