Low-level HIV-1 viraemia in patients on HAART: risk factors and management in clinical practice

DORAVIR: a French national survey of people with HIV-1 treated with an antiretroviral regimen including doravirine

BACKGROUND

Doravirine is the latest NNRTI to be approved for the treatment of HIV-1 and has a different resistance profile from first-generation NNRTIs. Our aim was to investigate the virological efficacy of antiretroviral treatment including doravirine in people living with HIV-1 (PLWHIV), the factors associated with virological failure (VF) and those associated with the emergence of reverse transcriptase (RT) mutations in the case of VF.

METHODS

A retrospective national survey of PLWHIV who were either naive or experienced on antiretroviral treatment including doravirine was conducted. VF was defined as two consecutive plasma viral loads (VLs) of ≥50 copies/mL or one VL of ≥200 copies/mL. Genotypic resistance tests were interpreted using the Stanford (v9.4.1) and ANRS (v33) algorithms.

RESULTS

Of the 589 PLWHIV treated with a doravirine-containing regimen, 8.5% were naive and 91.5% had prior antiretroviral experience; 56.9% were infected with HIV-1 B subtype. Overall, 88.3% and 85.1% of participants were virologically controlled at Month (M)3 and M6 of doravirine treatment, respectively. In multivariable analysis, CRF02_AG subtype, higher zenith plasma HIV-1 RNA VL, doravirine initiation in the context of failure and baseline V179D mutation presence were associated with VF. Among 88 PLWHIV who experienced virological failure at M6, 15.9% had a median of 2 (IQR 1-3) HIV RT mutations. In multivariable analysis, the only factor associated with the occurrence of mutations was a genotypic sensitivity score that was not fully sensitive.

CONCLUSIONS

This study is one of the largest to characterize the virological efficacy of doravirine-containing regimens in clinical practice and to identify factors associated with VF or emergence of resistance mutations that should be considered in clinical management.

Factors Associated with Low-Level Viremia in People Living with HIV in the Italian Antiviral Response Cohort Analysis Cohort: A Case-Control Study

Despite effective antiretroviral therapies (ARTs), a subset of people living with HIV (PLWH) still experience low-level viremia (LLV, i.e., 50-1,000 copies/mL). The present study compared PLWH experiencing LLV with those maintaining virological suppression (VS) and explored the potential impact of preexisting drug resistance and other factors on LLV. We conducted a retrospective, 1:1 matched case-control study within a cohort of drug-experienced VS subjects from the Italian Antiviral Response Cohort Analysis database, followed in the period 2009-2019. Cases were individuals experiencing LLV, while controls were those who maintained VS. Matching was for calendar year of first ART regimen. Preexisting drug resistance was calculated as cumulative genotypic susceptibility score (GSS) according to regimen administered at the observational period start. To explore the effect of cumulative GSS, treated as a binary variable (≥2 and <2) and other factors on LLV, we performed a logistic regression analysis. Within a main population of 3,455 PLWH, 337 cases were selected. Cases were comparable to the controls for both gender and age. However, cases showed that they had experienced a longer time since HIV diagnosis, a higher number of drugs previously administered, lower baseline CD4+ T cell count and a higher zenith viral load (VL). By multivariate analysis, we found that higher zenith VL [adjusted odds ratio (aOR) (95% confidence interval [CI]) 1.30 (1.14-1.48)], a cumulative usage of both PI [aOR (95% CI): 2.03 (1.19-3.48)] and InSTI [aOR (95% CI): 2.23 (1.47-3.38)] and a cumulative GSS <2 [aOR (95% CI) 0.67 (0.46-0.98)], were associated with a higher risk in developing LLV. In current high-efficacy ART era, in drug-experienced PLWH, the predictors of increased risk of LLV were the presence of preexisting drug resistance, higher zenith VL, and previous PI, and InSTI exposure.

Prevalence and predictors of persistent low-level HIV viraemia: a retrospective cohort study among people receiving dolutegravir-based antiretroviral therapy in Southern Nigeria

Background

Persistent low-level viraemia (PLLV) is a risk factor for virologic failure among people receiving antiretroviral therapy (ART).

Objectives

We assessed the prevalence and predictors of PLLV among individuals receiving Dolutegravir-based ART in southern Nigeria.

Design

This retrospective cohort study used routine program data from electronic medical records of persons receiving Dolutegravir-based first-line ART in 154 PEPFAR/USAID-supported health facilities in Akwa Ibom and Cross Rivers states, Nigeria.

Methods

Clients on first-line Dolutegravir-based ART ⩾6 months, who had a viral load result in the 12 months preceding October 2021 (baseline), and a second viral load result by September 2022 were included. Persons with low-level viraemia (LLV) (viral load 51-999 copies/ml) received additional adherence support. The outcome analysed was PLLV (two consecutive LLV results). Indices were summarized using descriptive statistics, and predictors of PLLV were determined using multivariate logistic regression.

Results

In total, 141,208 persons on ART were included, of which 63.3% (n = 89,944) were females. The median age was 36 [29-44] years, median ART duration was 19 [11-42] months. At the end of the study, 10.5% (14,759/141,208) had initial LLV, 90.1% (13,304/14,759) of which attained undetectable viral load (⩽50 copies/ml), and 1.1% (163/14,759) transitioned to virologic failure (⩾1000 copies/ml) by the end of the study. PLLV prevalence was 0.9% (1292/141,208). Increasing ART duration [adjusted odds ratio (aOR) = 1.0; 95% confidence interval (CI): 1.005-1.008; p < 0.001] and viral suppression (<1000 copies/ml) before initial LLV (aOR = 1.7; 95% CI: 1.50-2.00; p < 0.001) were positively associated with PLLV, while receipt of tuberculosis preventive therapy reduced the likelihood of PLLV (aOR = 0.3; 95% CI: 0.10-0.94; p = 0.039).

Conclusion

PLLV was uncommon among individuals receiving dolutegravir-based ART and was associated with longer ART duration, prior viral suppression, and non-receipt of tuberculosis preventive therapy. This strengthens recommendations for continuous adherence support and comprehensive health services with ART, to prevent treatment failure.

Investigating rates and predictors of viral blips, low-level viraemia and virological failure in the Australian HIV observational database

OBJECTIVES

Australia has made significant progress towards achieving the UNAIDS's 95-95-95 cascade targets including HIV viral suppression. To investigate the burden of HIV viraemia, we assessed viral blips, low-level viraemia (LLV) and virologic failure (VF) in an Australian cohort.

METHODS

We studied the proportion of people with viral suppression, viral blips, LLV and VF in the Australian HIV observational database (AHOD) between 2010 and 2021. The association between blips or LLV, and VF was investigated using Cox regression, and predictors of viral blips and LLV were assessed using repeated-measured logistic regression.

RESULTS

Among 2544 AHOD participants who were in follow-up and on antiretroviral therapy (ART) from 1 January 2010 (88.7% male), 444 had experienced VF (incidence rate: 2.45 [95% CI: 2.23-2.69] per 100 person-years [PY]) during 18,125 PY of follow-up (a median of 7.6 years). The proportion of people with VF decreased over time, whereas rates of blips and LLV remained stable. Participants with blips (hazard ratio, 2.89; 95% CI: 2.31-3.61) and LLV (4.46; 95% CI: 3.38-5.89) were at increased risk of VF. Hepatitis B co-infection, longer documented treatment interruption duration, younger age and lower CD4 at ART initiation, and protease inhibitors-based initial regimen were associated with an increased risk of VF. Common predictors of blips and LLV such as higher HIV-1 RNA and lower CD4 at ART initiation, longer treatment interruption, more VL testing and types of care settings (hospitals vs. sexual health services) were identified.

CONCLUSIONS

Blips and LLV predict subsequent VF development. We identified important predictors of HIV viraemia including VF among individuals on INSTI-based regimens to help direct HIV management plans.

Plasma Human Immunodeficiency Virus 1 RNA and CD4+ T-Cell Counts Are Determinants of Virological Nonsuppression Outcomes With Initial Integrase Inhibitor-Based Regimens: A Prospective RESPOND Cohort Study

BACKGROUND

There are conflicting data regarding baseline determinants of virological nonsuppression outcomes in persons with human immunodeficiency virus (HIV) starting antiretroviral treatment (ART). We evaluated the impact of different baseline variables in the RESPOND cohort.

METHODS

We included treatment-naive participants aged ≥18 who initiated 3-drug ART, in 2014-2020. We assessed the odds of virological suppression (VS) at weeks 48 and 96 using logistic regression. Viral blips, low-level viremia (LLV), residual viremia (RV), and virological failure (VF) rates were assessed using Cox regression.

RESULTS

Of 4310 eligible participants, 72% started integrase strand transfer inhibitor (INSTI)-based regimens. At 48 and 96 weeks, 91.0% and 93.3% achieved VS, respectively. At 48 weeks, Kaplan-Meier estimates of rates were 9.6% for viral blips, 2.1% for LLV, 22.2% for RV, and 2.1% for VF. Baseline HIV-1 RNA levels >100 000 copies/mL and CD4+ T-cell counts ≤200/µL were negatively associated with VS at weeks 48 (adjusted odds ratio, 0.51 [95% confidence interval, .39-.68] and .40 [.27-.58], respectively) and 96 and with significantly higher rates of blips, LLV, and RV. CD4+ T-cell counts ≤200/µL were associated with higher risk of VF (adjusted hazard ratio, 3.12 [95% confidence interval, 2.02-4.83]). Results were consistent in those starting INSTIs versus other regimens and those starting dolutegravir versus other INSTIs.

CONCLUSIONS

Initial high HIV-1 RNA and low CD4+ T-cell counts are associated with lower rates of VS at 48 and 96 weeks and higher rates of viral blips, LLV, and RV. Low baseline CD4+ T-cell counts are associated with higher VF rates. These associations remain with INSTI-based and specifically with dolutegravir-based regimens. These findings suggest that the impact of these baseline determinants is independent of the ART regimen initiated.

Influencing factors and adverse outcomes of different virologic rebound states in antiretroviral treated HIV/AIDS patients

Antiretroviral therapy (ART) aims to inhibit HIV replication, decrease CD4 T cell loss, and immune function recovery in order to reduce the morbidity and mortality associated with the infection. Treatment should also, improve quality of life and control HIV spread. However, incomplete viral suppression still occurs during ART. Viral suppression and virological failure (VF) thresholds vary between studies in terms of virological rebound (VR) states using different detection thresholds. Further understanding of influencing factors and adverse outcomes in various VR states should provide important guidance for HIV treatment.

Virologic Failure Following Low-level Viremia and Viral Blips During Antiretroviral Therapy: Results From a European Multicenter Cohort

BACKGROUND

It is unclear whether low-level viremia (LLV), defined as repeatedly detectable viral load (VL) of <200 copies/mL, and/or transient viremic episodes (blips) during antiretroviral therapy (ART), predict future virologic failure. We investigated the association between LLV, blips, and virologic failure (VF) in a multicenter European cohort.

METHODS

People with HIV-1 who started ART in 2005 or later were identified from the EuResist Integrated Database. We analyzed the incidence of VF (≥200 copies/mL) depending on viremia exposure, starting 12 months after ART initiation (grouped as suppression [≤50 copies/mL], blips [isolated VL of 51-999 copies/mL], and LLV [repeated VLs of 51-199 copies/mL]) using Cox proportional hazard models adjusted for age, sex, injecting drug use, pre-ART VL, CD4 count, HIV-1 subtype, type of ART, and treatment experience. We queried the database for drug-resistance mutations (DRM) related to episodes of LLV and VF and compared those with baseline resistance data.

RESULTS

During 81 837 person-years of follow-up, we observed 1424 events of VF in 22 523 participants. Both blips (adjusted subhazard ratio [aHR], 1.7; 95% confidence interval [CI], 1.3-2.2) and LLV (aHR, 2.2; 95% CI, 1.6-3.0) were associated with VF, compared with virologic suppression. These associations remained statistically significant in subanalyses restricted to people with VL <200 copies/mL and those starting ART 2014 or later. Among people with LLV and genotype data available within 90 days following LLV, 49/140 (35%) had at least 1 DRM.

CONCLUSIONS

Both blips and LLV during ART are associated with increased risk of subsequent VF.

More HIV-1 RNA detected and quantified with the Cobas 6800 system in patients on antiretroviral therapy

BACKGROUND

Target-detected (TD) results or low-level viraemia (LLV) can be observed in HIV-1 patients on ART, which regularly raises questions.

OBJECTIVES

We describe here the impact on HIV-1 RNA quantification of switching from the COBAS AmpliPrep/COBAS TaqMan (CAP/CTM) to the Cobas 6800 system (C6800), based on analyses of viraemia close to the lower limit of quantification (LLoQ).

PATIENTS AND METHODS

We retrospectively selected two groups of patients: 200 individuals whose viral loads (VLs) were consistently <50 copies/mL with CAP/CTM for at least 3 years before switching to C6800 (group 1), and 35 other patients with confirmed LLV when C6800 was in use (group 2). In both groups, we compared several consecutive VL results performed before and after the change of quantification assay. Analyses were performed with McNemar's paired tests or Fisher's exact tests.

RESULTS

In group 1, the frequency of TD results (below or above the LLoQ) increased significantly after the switch to C6800 for patients with <25% of results being TD for VLs performed with CAP/CTM (P < 0.0001). Significantly more patients had at least one VL ≥20 or ≥50 copies/mL with C6800, in both group 1 (37.0% versus 18.5%; P < 0.0001 and 6.5% versus 0%; P = 0.0009, respectively) and group 2 (100% versus 66%; P = 0.0015 and 97% versus 40%; P < 0.0001, respectively).

CONCLUSIONS

C6800 revealed residual or low-level HIV-1 RNA that was not detected with CAP/CTM, resulting in twice as many patients being found to have a VL ≥20 copies/mL. Physicians and patients should be aware of possible differences in results between assays, and it is crucial to specify the quantitative assay used in studies.

Factors associated with low-level viraemia in people with HIV starting antiretroviral therapy: A Swedish observational study

Objective

Low-level viraemia (LLV) occurs in some people with HIV (PWH) receiving antiretroviral therapy (ART) and has been linked to inferior treatment outcomes. We investigated factors associated with LLV in a nationwide cohort of Swedish PWH starting ART.

Methods

Participants were identified from the InfCareHIV register, with the following inclusion criteria: ART initiation 2006–2017, age >15 years, ≥4 viral load (VL) results available and no documented treatment interruptions or virologic failure (≥2 consecutive VL ≥200 copies/ml) during follow-up. Starting from 6 months after ART initiation, participants were followed for 24 months and categorised as viral suppression (VS; VL <50 copies/ml) or LLV (≥2 consecutive VL 50–199 copies/ml). We analysed the association between the following factors and LLV using multivariable logistic regression: sex, age, pre-ART VL and CD4 count, ART regimen, country of birth, HIV-1 subtype and transmission category.

Results

Among 3383 participants, 3132 (92.6%) had VS and 251 (7.4%) had LLV. In univariable analyses, factors associated with LLV were male sex, higher age, lower pre-ART CD4 count, higher pre-ART VL and ART regimen. After adjustment, the following factors were associated with LLV (adjusted odds ratio; 95% confidence interval): male sex (1.6; 1.1–2.3), higher pre-ART VL (2.7; 2.2–3.3), pre-ART CD4 count <200 cells/μl (1.6; 1.2–2.2), protease inhibitor (PI)-based regimen (1.5; 1.1–2.1), non-standard ART (2.4; 1.0–5.5) and injecting drug use (2.0; 1.1–3.7).

Conclusion

Among Swedish PWH, LLV during ART was associated with markers of HIV disease severity before starting ART, male sex, injecting drug use and use of PI-based or non-standard ART regimens.

HIV-1 drug resistance mutations among individuals with low-level viraemia while taking combination ART in Botswana

OBJECTIVES

To assess whether a single instance of low-level viraemia (LLV) is associated with the presence of drug resistance mutations (DRMs) and predicts subsequent virological failure (VF) in adults receiving ART in 30 communities participating in the Botswana Combination Prevention Project.

METHODS

A total of 6078 HIV-1 C pol sequences were generated and analysed using the Stanford HIV drug resistance database. LLV was defined as plasma VL = 51-999 copies/mL and VF was defined as plasma VL ≥ 1000 copies/mL.

RESULTS

Among 6078 people with HIV (PWH), 4443 (73%) were on ART for at least 6 months. Of the 332 persons on ART with VL > 50 copies/mL, 175 (4%) had VL ≥ 1000 copies/mL and 157 (4%) had LLV at baseline. The prevalence of any DRM was 57 (36%) and 78 (45%) in persons with LLV and VL ≥ 1000 copies/mL, respectively. Major DRMs were found in 31 (20%) with LLV and 53 (30%) with VL ≥ 1000 copies/mL (P = 0.04). Among the 135 PWH with at least one DRM, 17% had NRTI-, 35% NNRTI-, 6% PI- and 3% INSTI-associated mutations. Among the 3596 participants who were followed up, 1709 (48%) were on ART for ≥6 months at entry and had at least one subsequent VL measurement (median 29 months), 43 (3%) of whom had LLV. The OR of experiencing VF in persons with LLV at entry was 36-fold higher than in the virally suppressed group.

CONCLUSIONS

A single LLV measurement while on ART strongly predicted the risk of future VF, suggesting the use of VL > 50 copies/mL as an indication for more intensive adherence support with more frequent VL monitoring.

Low-level viremia in treated HIV-1 infected patients: advances and challenges

Antiretroviral therapy (ART) can effectively suppress HIV-1 replication, improving quality of life and restoring the lifespan of persons living with HIV (PLWH) to near normal levels. However, after standardized ART, a low level of HIV-1 RNA, i.e., low-level viremia (LLV), may still be identified in 3% to 10% of the patients. LLV is capable of impacting the immunological and clinical outcome of patients and serves as a risk factor for transmission. The underlying mechanism of LLV is not yet certain, and the effects of LLV on patient outcomes remain under evaluation. Understanding LLV will allow effective prevention and control strategies to be designed for the benefit of PLWH.

Virological outcome and frequency of low-level viremia in patients receiving generic dolutegravir-containing regimen at a large tertiary care clinic in Western India

Background

Dolutegravir (DTG) is widely used for the management of naïve and treatment-experienced HIV-infected patients. Low-level viremia (LLV) is common in patients receiving nonnucleoside reverse transcriptase inhibitor- and protease inhibitor-containing regimens. However, the incidence of LLV associated with DTG-containing regimen is not well known.

Objective

The objective of this study was to assess the virological response associated with DTG-containing regimens and explored frequencies of LLV and risk factors for the same.

Methods

We performed a retrospective cohort study of HIV-infected patients receiving generic DTG-containing regimen from February 2017 to July 2019. All adult patients (≥18 years), who completed at least the first follow-up after initiating treatment, were included in this study. LLV was defined as plasma viral load between 20 and 200 copies/ml.

Results

A total of 597 patients started DTG-containing regimen during the study period, of which 522 patients met the inclusion criteria. The study patients were categorized into five groups: naïve (n = 86), first-line failure (n = 32), second-line failure (n = 53), switch (n = 325), and HIV-2 (n = 26). Complete virological suppression at 6, 12, and 18 months was achieved in 78.5%, 81.1%, and 70.9% of the patients, respectively. Furthermore, 17.9%, 12.9%, and 23.3% of the patients had LLV at 6, 12, and 18 months, respectively. Persistent LLV was found in 2.9% of the patients. Overall, DTG was well tolerated and was discontinued in only three patients due to neuropsychiatric side effects.

Conclusion

DTG is well tolerated and effective in suppressing HIV across all antiretroviral treatment categories. The rate of persistent LLV is low in DTG-containing therapy.

Persistent low-level viraemia in antiretroviral treatment-experienced patients is not linked to viral resistance or inadequate drug concentrations

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 ≥50 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 45.2-57.9), last CD4 count of 658 cells/mm3 (IQR 462-909) and total ART duration of 10.2 years (IQR 5.7-15.2). LLV duration was 14.0 months (IQR 5.5-22.3). 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 2.44-2.86). 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 <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.

Hijacking the Fusion Complex of Human Parainfluenza Virus as an Antiviral Strategy

Paramyxoviruses, including human parainfluenza virus type 3, are internalized into host cells by fusion between viral and target cell membranes. The receptor binding protein, hemagglutinin-neuraminidase (HN), upon binding to its cell receptor, triggers conformational changes in the fusion protein (F). This action of HN activates F to reach its fusion-competent state. Using small molecules that interact with HN, we can induce the premature activation of F and inactivate the virus. To obtain highly active pretriggering compounds, we carried out a virtual modeling screen for molecules that interact with a sialic acid binding site on HN that we propose to be the site involved in activating F. We use cryo-electron tomography of authentic intact viral particles for the first time to directly assess the mechanism of action of this treatment on the conformation of the viral F protein and present the first direct observation of the induced conformational rearrangement in the viral F protein.

The receptor binding protein of parainfluenza virus, hemagglutinin-neuraminidase (HN), is responsible for actively triggering the viral fusion protein (F) to undergo a conformational change leading to insertion into the target cell and fusion of the virus with the target cell membrane. For proper viral entry to occur, this process must occur when HN is engaged with host cell receptors at the cell surface. It is possible to interfere with this process through premature activation of the F protein, distant from the target cell receptor. Conformational changes in the F protein and adoption of the postfusion form of the protein prior to receptor engagement of HN at the host cell membrane inactivate the virus. We previously identified small molecules that interact with HN and induce it to activate F in an untimely fashion, validating a new antiviral strategy. To obtain highly active pretriggering candidate molecules we carried out a virtual modeling screen for molecules that interact with sialic acid binding site II on HN, which we propose to be the site responsible for activating F. To directly assess the mechanism of action of one such highly effective new premature activating compound, PAC-3066, we use cryo-electron tomography on authentic intact viral particles for the first time to examine the effects of PAC-3066 treatment on the conformation of the viral F protein. We present the first direct observation of the conformational rearrangement induced in the viral F protein.

Community Based Antiretroviral Treatment in Rural Zimbabwe

Treatment of HIV has reduced HIV/AIDS-related mortality. Sustaining >90% virologic suppression in sub-Saharan Africa requires decentralized care and prevention services to rural communities. In Zimbabwe, the number of people receiving antiretroviral treatment (ART) has increased rapidly. However, access to treatment monitoring tools such as viral load and drug resistance testing is limited. We assessed virologic treatment outcomes among ART recipients in Nyamutora, a rural community receiving bimonthly ART and prevention services. We enrolled all ART recipients (143) at 6-monthly visits in the Nyamutora community in 2014 and 2015. Whole blood samples were collected in K-EDTA tubes, transported to Harare for CD4 counts and viral load testing, and genotype was obtained in participants with viral loads >1,000 copies/ml. Ages ranged from 2 to 75 years (median 43 years) with a median 42 months on ART at follow-up. Eight of 143 (6%) had viral loads >1,000 copies/ml at one of the 3 visits, 7 on first-line nevirapine (NVP)-based ART and 1 on second-line LPV/r-based ART. Seven participants had sequence data available, and five had drug resistance mutations, K65R, T69N, K101E, K103N, Y181C/I, M184V, and G190A. Virologic failure (p = .001) and drug resistance mutations (p = .01) on first-line NVP-based ART were associated with younger age by univariate exact logistic regression. The participants had high viral suppression (94%) despite less than optimal (NVP based) ART regimens without laboratory monitoring. Virologic failure and drug resistance were higher among children and adolescents. Effective ART delivery to the community achieved high rates of virologic suppression and minimal drug resistance.

Prevalence of HIV-1 drug resistance in treated patients with viral load >50 copies/mL: a 2014 French nationwide study

Background

Surveillance of HIV-1 resistance in treated patients with a detectable viral load (VL) is important to monitor, in order to assess the risk of spread of resistant viruses and to determine the proportion of patients who need new antiretroviral drugs with minimal cross-resistance.

Methods

The HIV-1 protease and reverse transcriptase (RT) and integrase genes were sequenced in plasma samples from 782 consecutive patients on failing antiretroviral regimens, seen in 37 specialized centres in 2014. The genotyping results were interpreted using the ANRS v24 algorithm. Prevalence rates were compared with those obtained during a similar survey conducted in 2009.

Results

The protease and RT sequences were obtained in 566 patients, and the integrase sequence in 382 patients. Sequencing was successful in 60%, 78%, 78% and 87% of patients with VLs of 51-200, 201-500, 501-1000 and >1000 copies/mL, respectively. Resistance to at least one antiretroviral drug was detected in 56.3% of samples. Respectively, 3.9%, 8.7%, 1.5% and 3.4% of patients harboured viruses that were resistant to any NRTI, NNRTI, PI and integrase inhibitor (INI). Resistance rates were lower in 2014 than in 2009. Resistance was detected in 48.5% of samples from patients with a VL between 51 and 200 copies/mL.

Conclusion

In France in 2014, 90.0% of patients in AIDS care centres were receiving antiretroviral drugs and 12.0% of them had VLs >50 copies/mL. Therefore, this study suggests that 6.7% of treated patients in France might transmit resistant strains. Resistance testing may be warranted in all treated patients with VL > 50 copies/mL.

CD4+/CD8+ ratio restoration in long-term treated HIV-1-infected individuals

OBJECTIVES

A persistently low CD4/CD8 ratio despite virological control reflects a higher risk of morbidity in HIV-infected individuals. The objective of the study was to assess the probability and determinants of ratio restoration (≥1) during long-term combined antiretroviral therapy (cART).

DESIGN

Study cohort based on the French Hospital Database on HIV (ANRS CO4).

METHODS

Antiretroviral-naive HIV-1-infected individuals were included if they achieved virological control (plasma HIV RNA ≤ 500 copies/ml) within 9 months following cART, started between 2000 and 2010. Cumulative incidence of ratio restoration after virological control and predictive factors of such a favorable outcome were studied taking into account 'virological failure', 'loss to follow-up', and 'death' as competing risks for ratio restoration.

RESULTS

Among the 10012 individuals included, the probability of CD4/CD8 ratio restoration was 30% (95% confidence interval, 29-31) at 8 years, ranging from 17% (15 to 19) among individuals with AIDS, to 45% (41 to 50) in people with CD4 at least 500 cells/μl at cART introduction. The main factors associated with ratio restoration were cART started during primary HIV infection whatever the CD4 cell count, or starting at CD4 at least 500 cells/μl while not in primary HIV infection [subdistribution hazard ratio = 1.67 (95% confidence interval, 1.13-2.47) and 2.26 (1.92-2.66) respectively, compared with starting cART at 200-349 CD4 cells/μl], and starting cART in recent years [subdistribution hazard ratio = 2.38 (2.01-2.83) in 2009-2010, compared with 2000-2002]. Higher baseline CD8 cell count was negatively associated with ratio restoration.

CONCLUSION

At 8 years, only one-third of individuals achieved CD4/CD8 ratio restoration with sustained virological control. Treatment at the earliest stage, and starting cART in recent years appeared to be key determinants.

Pre-treatment minority HIV-1 drug resistance mutations and long term virological outcomes: is prediction possible?

Background

Although the use of highly active antiretroviral therapy in HIV positive individuals has proved to be effective in suppressing the virus to below detection limits of commonly used assays, virological failure associated with drug resistance is still a major challenge in some settings. The prevalence and effect of pre-treatment resistance associated variants on virological outcomes may also be underestimated because of reliance on conventional population sequencing data which excludes minority species. We investigated long term virological outcomes and the prevalence and pattern of pre-treatment minority drug resistance mutations in individuals initiating HAART at a local HIV clinic.

Methods

Patient’s records of viral load results and CD4 cell counts from routine treatment monitoring were used and additional pre-treatment blood samples for Sanger sequencing were obtained. A selection of pre-treatment samples from individuals who experienced virological failure were evaluated for minority resistance associated mutations to 1 % prevalence and compared to individuals who achieved viral suppression.

Results

At least one viral load result after 6 months or more of treatment was available for 65 out of 78 individuals followed for up to 33 months. Twenty (30.8 %) of the 65 individuals had detectable viremia and eight (12.3 %) of them had virological failure (viral load > 1000 RNA copies/ml) after at least 6 months of HAART. Viral suppression, achieved by month 8 to month 13, was followed by low level viremia in 10.8 % of patients and virological failure in one patient after month 20. There was potentially reduced activity to Emtricitabine or Tenofovir in three out of the eight cases in which minority drug resistance associated variants were investigated but detectable viremia occurred in one of these cases while the activity of Efavirenz was generally reduced in all the eight cases.

Conclusions

Early viral suppression was followed by low level viremia for some patients which may be an indication of failure to sustain viral suppression over time. The low level viremia may also be representing early stages of resistance development. The mutation patterns detected in the minority variants showed potential reduced drug sensitivity which highlights their potential to dominate after treatment initiation.

Trial registration

Not applicable.

Electronic supplementary material

The online version of this article (doi:10.1186/s12985-016-0628-x) contains supplementary material, which is available to authorized users.