HIV drug resistance detected during low-level viraemia is associated with subsequent virologic failure

Managing low-level HIV viraemia in antiretroviral therapy: a systematic review and meta-analysis

OBJECTIVE

HIV-1 management has advanced significantly with antiretroviral therapy (ART), yet challenges persist, including low-level HIV-1 viraemia (LLV). LLV presents a complex scenario, with varied definitions in the literature, reflecting uncertainties in its clinical interpretation. Questions arise regarding the underlying mechanisms of LLV, whether it signifies ongoing viral replication or stems from other factors. This study aimed to systematically review strategies for LLV management, providing insights into optimal clinical approaches.

METHODS

MEDLINE, EMBASE, Cochrane Library, Web of Science and Canadian Agency for Drugs and Technologies in Health were searched for relevant literature on LLV management. We included studies published between 2004 and 2024, assessing interventions such as ART modification, genotypic resistance testing, adherence assessment, performing therapeutic drug monitoring, testing for chronic coinfections and assessing the viral reservoir via HIV DNA quantification. Meta-analyses were conducted where feasible.

RESULTS

The systematic review identified 48 eligible records. Findings indicated limited evidence supporting the effectiveness of ART regimen modification in achieving virological suppression among individuals with LLV. However, studies assessing genotypic resistance testing revealed a significant association between resistance-associated mutations and virological suppression during LLV. Adherence to ART emerged as a critical determinant of treatment efficacy, with interventions showing promise in achieving viral suppression. The clinical utility of therapeutic drug monitoring in managing LLV remained inconclusive. Gaps in the literature were identified regarding follow-up scheduling, managing concurrent chronic infections and assessing inflammatory markers in LLV management.

CONCLUSIONS

While ART modification may not consistently achieve virological suppression, genotypic resistance testing may offer insights into treatment outcomes. Adherence to ART emerged as a crucial factor, necessitating tailored interventions. However, further research is needed to elucidate the clinical utility of therapeutic drug monitoring and other management strategies. The study highlights the importance of ongoing research to refine therapeutic approaches and improve patient outcomes in LLV management.

PROSPERO REGISTRATION NUMBER

CRD42024511492.

Management of low-level HIV viremia during antiretroviral therapy: Delphi consensus statement and appraisal of the evidence

OBJECTIVE

While antiretroviral therapy (ART) is highly effective, detection of low levels of HIV-1 RNA in plasma is common in treated individuals. Given the uncertainties on the topic, we convened a panel of experts to consider different clinical scenarios, producing a Delphi consensus to help guide clinical practice.

METHODS

A panel of 17 experts in infectious diseases, virology and immunology rated 32 statements related to four distinct scenarios: (1) low-level viremia during stable (≥6 months) first-line ART (≥2 consecutive HIV-1 RNA measurements 50-500 copies/mL); (2) a viral blip during otherwise suppressive ART (a HIV-1 RNA measurement 50-1000 copies/mL with adjacent measurements <50 copies/mL); (3) low-level viral rebound during previously suppressive ART (≥2 consecutive HIV-1 RNA measurements 50-500 copies/mL); (4) residual viremia during suppressive ART (persistent HIV-1 RNA quantification below 50 copies/mL). A systematic review, conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-analysis statement, informed the 32 statements. The Delphi procedure was modified to include two voting rounds separated by a moderated group discussion. Grading of Recommendations, Assessment, Development, and Evaluations-based recommendations were developed.

RESULTS

Overall, 18/32 statements (56.2%) achieved a strong consensus, 3/32 (9.4%) achieved a moderate consensus and 11/32 (34.4%) did not achieve a consensus. Across the four scenarios, the panel unanimously emphasised the importance of implementing specific interventions prior to considering therapy changes, including assessing adherence, testing for genotypic drug resistance and scheduling more frequent follow-up visits. Strategies indicated in selected circumstances included therapeutic drug monitoring, quantifying total HIV-1 DNA and evaluating concomitant chronic infections.

CONCLUSIONS

While acknowledging the many uncertainties about source, significance and optimal management of low-level viremia during ART, the findings provide insights to help harmonise clinical practice. There is a need for well-designed randomised studies assessing different interventions to manage low-level viremia and future research regarding its definition.

Comparison of Different HIV-1 Resistance Interpretation Tools for Next-Generation Sequencing in Italy

BACKGROUND

Next-generation sequencing (NGS) is gradually replacing Sanger sequencing for HIV genotypic drug resistance testing (GRT). This work evaluated the concordance among different NGS-GRT interpretation tools in a real-life setting.

METHODS

Routine NGS-GRT data were generated from viral RNA at 11 Italian laboratories with the AD4SEQ HIV-1 Solution v2 commercial kit. NGS results were interpreted by the SmartVir system provided by the kit and by two online tools (HyDRA Web and Stanford HIVdb). NGS-GRT was considered valid when the coverage was >100 reads (100×) at each PR/RT/IN resistance-associated position listed in the HIVdb 9.5.1 algorithm.

RESULTS

Among 629 NGS-GRT, 75.2%, 74.2%, and 70.9% were valid according to SmartVir, HyDRA Web, and HIVdb. Considering at least two interpretation tools, 463 (73.6%) NGS-GRT had a valid coverage for resistance analyses. The proportion of valid samples was affected by viremia <10,000-1000 copies/mL and non-B subtypes. Mutations at an NGS frequency >10% showed fair concordance among different interpretation tools.

CONCLUSION

This Italian survey on NGS resistance testing suggests that viremia levels and HIV subtype affect NGS-GRT coverage. Within the current routine method for NGS-GRT, only mutations with frequency >10% seem reliably detected across different interpretation tools.

Resistance to protease inhibitors among persons living with HIV in Ghana: a case for viral load and drug resistance monitoring

OBJECTIVE

Routine viral load and drug resistance testing are well supported in most resource-rich settings and provide valuable benefits in the clinical care of PLWH in these communities. Undoubtedly, there exist financial and political constraints for the scale-up of viral load and drug resistance testing in Sub-Saharan Africa. To achieve the global UNAIDS 95/95/95 targets, there is the need to bridge this inequity in patient care and allow for a universal approach that leaves no community behind.

METHODS

Venous blood from 96 PLWH on second-line ART from Korle-Bu Teaching Hospital were collected and processed into plasma for CD4+ T- cell and viral load assessments. Ribonucleic acid (RNA) was extracted from stored plasma and the protease gene amplified, sequenced and analyzed for subtype and drug resistance mutations using the Stanford HIV drug resistance database.

RESULTS

Out of the 96 PLWH, 37 experienced virological failure with 8 patients' samples successfully sequenced. The predominant HIV-1 subtype identified was CRF02_AG (6/8, 75.0%) with 12.5% (1/8) each of CFR06_cpx infection and one case unable to subtype. The major PI resistance mutations identified were; M46I, I54V, V82A, I47V, I84V and L90M.

CONCLUSIONS

Persons living with HIV who had experienced virologic failure in this study harboured drug resistance mutations to PI, thus compromise the effectiveness of the drugs in the second line. Resistance testing is strongly recommended prior to switching to a new regimen. This will help to inform the choice of drug and to achieve optimum therapeutic outcome among PLWH in Ghana.

HIV-1 low-level viraemia predicts virological failure in first-line and second-line ART-experienced individuals in India: A retrospective longitudinal study

OBJECTIVE

To study the prevalence of low-level viraemia (LLV) and its association with virological failure (VF).

METHODS

We conducted a retrospective analysis of 3498 participants at YRG CARE, Chennai, India (2013-2018) on antiretroviral therapy (ART) for ≥6 months with two or more plasma viral load (pVL) measurements. Results were stratified for those with pVL <1000 copies/mL: fully suppressed (FS) (pVL <40), low-LLV (pVL 40-199), mid-LLV (pVL 200-399), and high-LLV (pVL 400-999). The study assessed the association with VF (pVL >1000 copies/mL) using Cox proportional hazard model.

RESULTS

Among 3498 participants, 2965 (84.8%) were FS and 533 (15.2%) were LLV. During the follow-up, 348 (10%) experienced VF, with 222 (6.3%) experienced after LLV (42% of LLV) and 126 (3.6%) experienced after FS (4.3% of FS). When compared with FS, those with LLV had a greater risk of VF [adjusted hazard ratio (aHR) = 12.7; 95% confidence interval (CI): 10.2-15.9]. First-line participants had a higher VF incidence (aHR = 15.8, 95% CI: 11.4-21.9) than second-line participants (aHR = 5.6, 95% CI: 4.1-7.7). Those with high-LLV had the highest VF risk (aHR = 22.856, 95% CI: 15.204-34.359 vs. aHR = 8.186, 95% CI: 5.564-12.043, for first-line vs. second-line participants, respectively), followed by those with mid-LLV (aHR = 13.375, 95% CI: 8.327-21.483 vs. aHR = 6.261, 95% CI: 4.044-9.695) and low-LLV (aHR = 12.976, 95% CI: 7.974-21.118 vs. aHR = 4.158, 95% CI: 2.826-6.119).

CONCLUSIONS

The prevalence of LLV was intermediate in our study population. There was a higher risk of VF among individuals with LLV, and this risk increased with the increasing levels of LLV. Close monitoring of individuals experiencing LLV could help in the early identification of VF.

Low-Level Viremia among Adults Living with HIV on Dolutegravir-Based First-Line Antiretroviral Therapy Is a Predictor of Virological Failure in Botswana

We evaluated subsequent virologic outcomes in individuals experiencing low-level virem ia (LLV) on dolutegravir (DTG)-based first-line antiretroviral therapy (ART) in Botswana. We used a national dataset from 50,742 adults who initiated on DTG-based first-line ART from June 2016-December 2022. Individuals with at least two viral load (VL) measurements post three months on DTG-based first-line ART were evaluated for first and subsequent episodes of LLV (VL:51-999 copies/mL). LLV was sub-categorized as low-LLV (51-200 copies/mL), medium-LLV (201-400 copies/mL) and high-LLV (401-999 copies/mL). The study outcome was virologic failure (VF) (VL ≥ 1000 copies/mL): virologic non-suppression defined as single-VF and confirmed-VF defined as two-consecutive VF measurements after an initial VL < 1000 copies/mL. Cox regression analysis identified predictive factors of subsequent VF. The prevalence of LLV was only statistically different at timepoints >6-12 (2.8%) and >12-24 (3.9%) (p-value < 0.01). LLV was strongly associated with both virologic non-suppression (adjusted hazards ratio [aHR] = 2.6; 95% CI: 2.2-3.3, p-value ≤ 0.001) and confirmed VF (aHR = 2.5; 95% CI: 2.4-2.7, p-value ≤ 0.001) compared to initially virally suppressed PLWH. High-LLV (HR = 3.3; 95% CI: 2.9-3.6) and persistent-LLV (HR = 6.6; 95% CI: 4.9-8.9) were associated with an increased hazard for virologic non-suppression than low-LLV and a single-LLV episode, respectively. In a national cohort of PLWH on DTG-based first-line ART, LLV > 400 copies/mL and persistent-LLV had a stronger association with VF. Frequent VL testing and adherence support are warranted for individuals with VL > 50 copies/mL.

Effectiveness of intensive adherence counselling in achieving an undetectable viral load among people on antiretroviral therapy with low-level viraemia in Uganda

INTRODUCTION

Uganda was using a threshold of 1000 copies/mL to determine viral non-suppression for antiretroviral therapy monitoring among people living with HIV, prior to this study. It was not clear whether people living with HIV with low-level viraemia (LLV, ≥50 to <1000 copies/mL) would benefit from intensive adherence counselling (IAC). The purpose of this study was to determine the effectiveness of IAC among people living with HIV, receiving antiretroviral therapy, and with LLV in Uganda, to guide key policy decisions in HIV care, including the review of the viral load (VL) testing algorithm.

METHODS

This cluster-randomized clinical trial comprised adults from eight HIV clinics who were living with HIV, receiving ART, and had recent VL results indicating LLV (tested from July 2022 to October 2022). Participants in the intervention arm clinics received three once-monthly sessions of IAC, and those in the comparison non-intervention arm clinics received the standard of care. At the end of the study, all participants were re-tested for VL to determine the proportions of those who then had an undetectable VL (<50 copies/mL). We assessed the statistical association between cross-tabulated variables using Fisher's exact test and then modified Poisson regression.

RESULTS

A total of 136 participants were enrolled into the study at eight HIV clinics. All 68 participants in the intervention arm completed all IAC sessions. Only one participant in the non-intervention arm was lost to follow-up. The average follow-up time was 3.7 months (standard deviation [SD] 0.2) and 3.5 months (SD 0.1) in the intervention and non-intervention arms, respectively. In total, 59 (43.7%) of 135 people living with HIV achieved an undetectable VL during the study follow-up period. The effect of IAC on attaining an undetectable VL among people with LLV was nearly twice as high in the intervention arm (57.4%) than in the non-intervention arm (29.9%): adjusted risk ratio 1.9 (95% confidence interval 1.0-3.5), p = 0.037.

CONCLUSION

IAC doubled the likelihood of an undetectable VL among people living with HIV with LLV. Therefore, IAC has been instituted as an intervention to manage people living with HIV with LLV in Uganda, and this should also be adopted in other Sub-Saharan African countries with similar settings.

CLINICALTRIALS

GOV IDENTIFIER

NCT05514418.

Clinical Relevance of Human Immunodeficiency Virus Low-level Viremia in the Dolutegravir era: Data From the Viral Load Cohort North-East Lesotho (VICONEL)

Background

Human immunodeficiency virus low-level viremia (LLV) is associated with subsequent treatment failure at least with non nucleoside reverse transcriptase inhibitor (NNRTI)-containing antiretroviral therapy. Data on implications of LLV occurring under dolutegravir, which has largely replaced NNRTIs in Africa, are scarce, however.

Methods

We included adults with human immunodeficiency virus in Lesotho who had ≥2 viral loads (VLs) taken after ≥6 months of NNRTI- or dolutegravir-based antiretroviral therapy. Within VL pairs, we assessed the association of viral suppression (<50 copies/mL) and low- and high-range LLV (50-199 and 200-999 copies/mL, respectively) with virological failure (≥1000 copies/mL) using a mixed-effects regression model. Participants could contribute VLs to the NNRTI and the dolutegravir group.

Results

Among 18 550 participants, 12 216 (65.9%) were female and median age at first VL included was 41.2 years (interquartile range, 33.4-51.5). In both groups, compared with a suppressed VL, odds of subsequent virological failure were higher for low-range LLV (NNRTI: adjusted odds ratio; 95% confidence interval: 1.9; 1.4-2.4 and dolutegravir: 2.1; 1.3-3.6) and high-range LLV (adjusted odds ratio; 95% confidence interval, 4.2; 3.1-5.7 and 4.4; 2.4-7.9).

Conclusions

In the dolutegravir era, LLV remains associated with virological failure, endorsing the need for close clinical and laboratory monitoring of those with a VL ≥50 copies/mL.

Dynamics of Low-Level Viremia and Immune Activation after Switching to a Darunavir-Based Regimen

There is an ongoing debate regarding whether low-level viremia (LLV), in particular persistent LLV, during HIV treatment with optimal adherence originates from low-level viral replication, viral production, or both. We performed an observational study in 30 individuals with LLV who switched to a boosted darunavir (DRV)-based therapy. In-depth virological analyses were used to characterize the viral population and the (activity) of the viral reservoir. Immune activation was examined using cell-bound and soluble markers. The primary outcome was defined as the effect on HIV-RNA and was categorized by responders (<50 cp/mL) or non-responders (>50 cp/mL). At week 24, 53% of the individuals were considered responders, 40% non-responders, and 7% could not be assigned. Sequencing showed no evolution or selection of drug resistance in the non-responders. Production of defective virus with mutations in either the protease (D25N) or RT active site contributed to persistent LLV in two individuals. We show that in about half of the study participants, the switch to a DRV-based regimen resulted in a viral response indicative of ongoing low-level viral replication as the cause of LLV before the switch. Our data confirm that in clinical management, high genetic barrier drugs like DRV are a safe choice, irrespective of the source of LLV.

Reaching HIV epidemic control in Nigeria using a lower HIV viral load suppression cut-off

BACKGROUND

Virologic suppression has been defined using a HIV viral load of less than 1000 copies/ml. Low-level viremia (51-999 copies/ml) is associated with an increased risk of virologic failure and HIV drug resistance.

METHODS

Retrospective data from persons with HIV (PWH) who initiated ART between January 2016 and September 2022 in Nigeria were analyzed for virologic suppression at cut-off values less than 1000 copies/ml.

RESULTS

In 2022, virologic suppression at less than 1000 copies/ml was 95.7%. Using cut-off values of less than 400, less than 200 and less than 50 copies/ml, virologic suppression was 94.2%, 92.5%, and 87%, respectively.

DISCUSSION

Monitoring virologic suppression using lower cut-off values, alongside differentiated management of low-level viremia, may help Nigeria achieve HIV epidemic control targets.

Retrospective longitudinal analysis of low-level viremia among HIV-1 infected adults on antiretroviral therapy in Kenya

Background

HIV low-level viremia (LLV) (51-999 copies/mL) can progress to treatment failure and increase potential for drug resistance. We analyzed retrospective longitudinal data from people living with HIV (PLHIV) on antiretroviral therapy (ART) in Kenya to understand LLV prevalence and virologic outcomes.

Methods

We calculated rates of virologic suppression (≤50 copies/mL), LLV (51-999 copies/mL), virologic non-suppression (≥1000 copies/mL), and virologic failure (≥2 consecutive virologic non-suppression results) among PLHIV aged 15 years and older who received at least 24 weeks of ART during 2015-2021. We analyzed risk for virologic non-suppression and virologic failure using time-dependent models (each viral load (VL) <1000 copies/mL used to predict the next VL).

Findings

Of 793,902 patients with at least one VL, 18.5% had LLV (51-199 cp/mL 11.1%; 200-399 cp/mL 4.0%; and 400-999 cp/mL 3.4%) and 9.2% had virologic non-suppression at initial result. Among all VLs performed, 26.4% were LLV. Among patients with initial LLV, 13.3% and 2.4% progressed to virologic non-suppression and virologic failure, respectively. Compared to virologic suppression (≤50 copies/mL), LLV was associated with increased risk of virologic non-suppression (adjusted relative risk [aRR] 2.43) and virologic failure (aRR 3.86). Risk of virologic failure increased with LLV range (aRR 2.17 with 51-199 copies/mL, aRR 3.98 with 200-399 copies/mL and aRR 7.99 with 400-999 copies/mL). Compared to patients who never received dolutegravir (DTG), patients who initiated DTG had lower risk of virologic non-suppression (aRR 0.60) and virologic failure (aRR 0.51); similarly, patients who transitioned to DTG had lower risk of virologic non-suppression (aRR 0.58) and virologic failure (aRR 0.35) for the same LLV range.

Interpretation

Approximately a quarter of patients experienced LLV and had increased risk of virologic non-suppression and failure. Lowering the threshold to define virologic suppression from <1000 to <50 copies/mL to allow for earlier interventions along with universal uptake of DTG may improve individual and program outcomes and progress towards achieving HIV epidemic control.

Funding

No specific funding was received for the analysis. HIV program support was provided by the President's Emergency Plan for AIDS Relief (PEPFAR) through the United States Centers for Disease Control and Prevention (CDC).

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.

Drug Resistance Profile Among HIV-1 Infections Experiencing ART with Low-Level Viral Load in Guangdong China During 2011-2022: A Retrospective Study

Background

Antiretroviral therapy (ART) efficiently reduces the morbidities and mortalities caused by HIV-1 infection and prevents the HIV epidemic. However, virologic failure (VF) occurs in some patients receiving ART experience, especially increases in those patients with intermittent or persistent low-level viremia (LLV). The presence of drug resistance mutations (DRMs) in LLV was a strong predictor of subsequent VF. The data on drug resistance (DR) or DRMs for HIV-1 infections at low-level viral load (LLVL) are limited in China.

Objective

To monitor the prevalence of HIV-1 drug resistance and to evaluate the risk factors associated with drug resistance in LLVL HIV-1 infections during ART in Guangdong, China.

Methods

Plasma samples with LLVL during ART in Guangdong Province between Jan 2011 and Dec 2022 were subjected to a modified reverse-transcription PCR with a pre-step of virus concentration by ultracentrifugation before extraction and the Sanger sequencing. Then, the genotypic resistance test was performed and DR was analyzed by the Stanford HIVDB program. Finally, DR-associated factors were identified by logistic regression analysis.

Results

We found that CRF01_AE (53.57%) and CRF07_BC (25.07%) were the dominant HIV-1 genotypes in LLVL in Guangdong between 2011 and 2022 but that the percentage of CRF01_AE showed a trend of decrease over time. M46 (1.49%), M184 (30.91%), and K103 (21.46%) were the dominant PI-, NRTI-, and NNRTI-associated mutations, respectively. The total DR rate was 47.06%. Specifically, PI (3.71%) showed a significantly lower DR rate than NNRTI (40.74%) and NRTI (34.14%). Duration of ART, initial ART regimen, ethnicity, and WHO clinical stages were associated with DR.

Conclusion

The drug resistance rate among the LLVL during ART in Guangdong, China is high. The risk factors associated with HIV drug resistance should be seriously considered for better control.

Hopes, joys and fears: Meaning and perceptions of viral load testing and low-level viraemia among people on antiretroviral therapy in Uganda: A qualitative study

Uganda applies the World Health Organization threshold of 1,000 copies/ml to determine HIV viral non-suppression. While there is an emerging concern of low-level viraemia (≥50 to <1,000 copies/ml), there is limited understanding of how people on antiretroviral therapy perceive viral load testing and low-level viremia in resource-limited settings. This qualitative study used the health belief model to explore the meaning that people living with HIV attach to viral load testing and low-level viraemia in Uganda. We used stratified purposive sampling to select people on antiretroviral therapy from eight high volume health facilities from the Central, Eastern, Northern and Western regions of Uganda. We used an interview guide, based on the health belief model, to conduct 32 in-depth interviews, which were audio-recorded and transcribed verbatim. Thematic analysis technique was used to analyze the data with the help of ATLAS.ti 6. The descriptions of viral load testing used by the participants nearly matched the medical meaning, and many people living with HIV understood what viral load testing was. Perceived benefits for viral load testing were the ability to show; the amount of HIV in the body, how the people living with HIV take their drugs, whether the drugs are working, and also guide the next treatments steps for the patients. Participants reported HIV stigma, lack of transport, lack of awareness for viral load testing, delayed and missing viral load results and few health workers as the main barriers to viral load testing. On the contrary, most participants did not know what low-level viraemia meant, while several perceived it as having a reduced viral load that is suppressed. Many people living with HIV are unaware about low-level viraemia, and hence do not understand its associated risks. Likewise, some people living with HIV are still not aware about viral load testing. Lack of transport, HIV stigma and delayed viral load results are major barriers to viral load testing. Hence, there is an imminent need to institute more strategies to create awareness about both low-level viraemia and viral load testing, manage HIV related stigma, and improve turnaround time for viral load results.

Transcriptome analysis of CD4+ T cells from HIV-infected individuals receiving ART with LLV revealed novel transcription factors regulating HIV-1 promoter activity

Some HIV-infected individuals receiving ART develop low-level viremia (LLV), with a plasma viral load of 50-1000 copies/mL. Persistent low-level viremia is associated with subsequent virologic failure. The peripheral blood CD4+ T cell pool is a source of LLV. However, the intrinsic characteristics of CD4+ T cells in LLV which may contribute to low-level viremia are largely unknown. We analyzed the transcriptome profiling of peripheral blood CD4+ T cells from healthy controls (HC) and HIV-infected patients receiving ART with either virologic suppression (VS) or LLV. To identify pathways potentially responding to increasing viral loads from HC to VS and to LLV, KEGG pathways of differentially expressed genes (DEGs) were acquired by comparing VS with HC (VS-HC group) and LLV with VS (LLV-VS group). Characterization of DEGs in key overlapping pathways showed that CD4+ T cells in LLV expressed higher levels of Th1 signature transcription factors (TBX21), toll-like receptors (TLR-4, -6, -7 and -8), anti-HIV entry chemokines (CCL3 and CCL4), and anti-IL-1β factors (ILRN and IL1R2) compared to VS. Our results also indicated activation of the NF-κB and TNF signaling pathways that could promote HIV-1 transcription. Finally, we evaluated the effects of 4 and 17 transcription factors that were upregulated in the VS-HC and LLV-VS groups, respectively, on HIV-1 promoter activity. Functional studies revealed that CXXC5 significantly increased, while SOX5 markedly suppressed HIV-1 transcription. In summary, we found that CD4+ T cells in LLV displayed a distinct mRNA profiling compared to that in VS, which promoted HIV-1 replication and reactivation of viral latency and may eventually contribute to virologic failure in patients with persistent LLV. CXXC5 and SOX5 may serve as targets for the development of latency-reversing agents.

The association between low-level viraemia and subsequent viral non-suppression among people living with HIV/AIDS on antiretroviral therapy in Uganda

BACKGROUND

Uganda's efforts to end the HIV epidemic by 2030 are threatened by the increasing number of PLHIV with low-level viraemia (LLV). We conducted a study to determine the prevalence of LLV and the association between LLV and subsequent viral non-suppression from 2016 to 2020 among PLHIV on ART in Uganda.

METHOD

This was a retrospective cohort study, using the national viral load (VL) program data from 2016 to 2020. LLV was defined as a VL result of at least 50 copies/ml, but less than 1,000 copies/ml. Multivariable logistic regression was used to determine the factors associated with LLV, and cox proportional hazards regression model was used to determine the association between LLV and viral non-suppression.

RESULTS

A cohort of 17,783 PLHIV, of which 1,466 PLHIV (8.2%) had LLV and 16,317 (91.8%) had a non-detectable VL was retrospectively followed from 2016 to 2020. There were increasing numbers of PLHIV with LLV from 2.0% in 2016 to 8.6% in 2020; and LLV was associated with male sex, second line ART regimen and being of lower age. 32.5% of the PLHIV with LLV (476 out of 1,466 PLHIV) became non-suppressed, as compared to 7.7% of the PLHIV (1,254 out of 16,317 PLHIV) with a non-detectable viral load who became non-suppressed during the follow-up period. PLHIV with LLV had 4.1 times the hazard rate of developing viral non-suppression, as compared to PLHIV with a non-detectable VL (adjusted hazard ratio was 4.1, 95% CI: 3.7 to 4.7, p < 0.001).

CONCLUSION

Our study indicated that PLHIV with LLV increased from 2.0% in 2016 to 8.6% in 2020, and PLHIV with LLV had 4.1 times the hazard rate of developing viral non-suppression, as compared to PLHIV with a non-detectable VL. Hence the need to review the VL testing algorithm and also manage LLV in Uganda.

HIV Virologic Failure among Patients with Persistent Low-Level Viremia in Nairobi, Kenya: It Is Time to Review the >1000 Virologic Failure Threshold

Persistent low-level viremia (PLLV) of 200-999 copies/ml has been reported as a risk factor for HIV virologic failure (VF). This retrospective study was aimed at characterizing patients with PLLV, determining factors associated with VF, and determining the effect of regimen change. Data were extracted from electronic medical records for HIV care and treatment. Patients' characteristics (N = 705) were as follows: a mean age of 42 years, majority female (55%), and 51% married. A majority (78.7%) had a history of opportunistic infections in their ART lifetime. To determine factors associated with VF, 187 records on patients who maintained PLLV and 12 on deceased patients at the time of data review were eliminated from the analysis, leaving 506 patient records. Out of the 506, 89% (451/506) suppressed VL to nondetectable levels while 11% (55/506) had VF, and the difference was significant (P = 0.0001). Virologic failure was significantly associated with ages 10-30 years (P < 0.05). Baseline VL ≥ 1000 (OR 3.929; P = 0.002) and 200-999 copies/ml (OR 4.062; P = 0.004) were associated with VF. During PLLV, factors associated with VF included the following: PLLV of 200-999 copies/ml (P < 0.05), viral blips (OR 4.545; P = 0.0001), mean maximum VL (P < 0.05), and age (P = 0.043). Married marital status was inversely associated with VF (OR 0.318; P = 0.026). Regimen change was not significantly associated with virologic outcomes. However, patients who switched regimens to the second line had a high risk of VF (P = 0.028; OR 3.203). Regimen change was significantly high (P < 0.05) among adolescents and patients with a start regimen of 2NRTI+1NNRTI. Most of the PLLV patients (89%) achieved nondetectable VL after their continued ART monitoring for at least 12 months. Therefore, PLLV was not an indicator of VF. However, a consistent VL of ≥200-999 copies/ml at baseline and more than 12 months of ART care and treatment were significantly associated with VF. Patients with VL 200-999 copies/ml, adolescents, and young adults require intensive ART monitoring and support.

HIV-1C in-House RNA-Based Genotyping Assay for Detection of Drug Resistance Mutations in Samples with Low-Level Viral Loads

Purpose

Monitoring HIV-1 drug resistance mutations (DRM) in treated patients on combination antiretroviral therapy (cART) with a detectable HIV-1 viral load (VL) is important for the selection of appropriate cART. Currently, there is limited data on HIV DRM at low-level viremia (LLV) (VL 401-999 copies/mL) due to the use of a threshold of VL ≥1000 copies/mL for HIV DRM testing. We here assess the performance of an in-house HIV drug resistance genotyping assay using plasma for the detection of DRM at LLV.

Methods

We used a total of 96 HIV plasma samples from the population-based Botswana Combination Prevention Project (BCPP). The samples were stratified by VL groups: 50 samples had LLV, defined as 401-999 copies/mL, and 46 had ≥1000 copies/mL. HIV pol (PR and RT) region was amplified and sequenced using an in-house genotyping assay with BigDye sequencing chemistry. Known HIV DRMs were identified using the Stanford HIV Drug Resistance Database. Genotyping success rate between the two groups was estimated and compared using the comparison of proportions test.

Results

The overall genotyping success rate was 79% (76/96). For VL groups, the genotyping success was 72% (36/50) at LLV and 87% (40/46) at VL ≥1000 copies/mL. Among generated sequences, the overall prevalence of individuals with at least 1 major or intermediate-associated DRM was 24% (18/76). The proportions of NNRTI-, NRTI- and PI-associated resistance mutations were 28%, 24%, and 0%, respectively. The most predominant mutations detected were K103N (18%) and M184V (12%) in NNRTI- and NRTI-associated mutations, respectively. The prevalence of DRM was 17% (6/36) at LLV and 30% (12/40) at VL ≥1000 copies/mL.

Conclusion

The in-house HIV genotyping assay successfully genotyped 72% of LLV samples and was able to detect 17% of DRM amongst them. Our results highlight the possibility and clinical significance of genotyping HIV among individuals with LLV.

Genotypic Resistance Testing of HIV-1 DNA in Peripheral Blood Mononuclear Cells

HIV-1 DNA exists in nonintegrated linear and circular episomal forms and as integrated proviruses. In patients with plasma viremia, most peripheral blood mononuclear cell (PBMC) HIV-1 DNA consists of recently produced nonintegrated virus DNA while in patients with prolonged virological suppression (VS) on antiretroviral therapy (ART), most PBMC HIV-1 DNA consists of proviral DNA produced months to years earlier. Drug-resistance mutations (DRMs) in PBMCs are more likely to coexist with ancestral wild-type virus populations than they are in plasma, explaining why next-generation sequencing is particularly useful for the detection of PBMC-associated DRMs. In patients with ongoing high levels of active virus replication, the DRMs detected in PBMCs and in plasma are usually highly concordant. However, in patients with lower levels of virus replication, it may take several months for plasma virus DRMs to reach detectable levels in PBMCs. This time lag explains why, in patients with VS, PBMC genotypic resistance testing (GRT) is less sensitive than historical plasma virus GRT, if previous episodes of virological failure and emergent DRMs were either not prolonged or not associated with high levels of plasma viremia. Despite the increasing use of PBMC GRT in patients with VS, few studies have examined the predictive value of DRMs on the response to a simplified ART regimen. In this review, we summarize what is known about PBMC HIV-1 DNA dynamics, particularly in patients with suppressed plasma viremia, the methods used for PBMC HIV-1 GRT, and the scenarios in which PBMC GRT has been used clinically.

Low-level viraemia among people living with HIV in Nigeria: a retrospective longitudinal cohort study

BACKGROUND

HIV transmission can occur with a viral load of at least 200 copies per mL of blood and low-level viraemia can lead to virological failure; the threshold level at which risk for virological failure is conferred is uncertain. To better understand low-level viraemia prevalence and outcomes, we analysed retrospective longitudinal data from a large cohort of people living with HIV on antiretroviral therapy (ART) in Nigeria.

METHODS

In this retrospective cohort study using previously collected longitudinal patient data, we estimated rates of virological suppression (≤50 copies per mL), low-level viraemia (51-999 copies per mL), virological non-suppression (≥1000 copies per mL), and virological failure (≥2 consecutive virological non-suppression results) among people living with HIV aged 18 years and older who initiated and received at least 24 weeks of ART at 1005 facilities in 18 Nigerian states. We analysed risk for low-level viraemia, virological non-suppression, and virological failure using log-binomial regression and mixed-effects logistic regression.

FINDINGS

At first viral load for 402 668 patients during 2016-21, low-level viraemia was present in 64 480 (16·0%) individuals and virological non-suppression occurred in 46 051 (11·4%) individuals. Patients with low-level viraemia had increased risk of virological failure (adjusted relative risk 2·20, 95% CI 1·98-2·43; p<0·0001). Compared with patients with virological suppression, patients with low-level viraemia, even at 51-199 copies per mL, had increased odds of low-level viraemia and virological non-suppression at next viral load; patients on optimised ART (ie, integrase strand transfer inhibitors) had lower odds than those on non-integrase strand transfer inhibitors for the same low-level viraemia range (eg, viral load ≥1000 copies per mL following viral load 400-999 copies per mL, integrase strand transfer inhibitor: odds ratio 1·96, 95% CI 1·79-2·13; p<0·0001; non-integrase strand transfer inhibitor: 3·21, 2·90-3·55; p<0·0001).

INTERPRETATION

Patients with low-level viraemia had increased risk of virological non-suppression and failure. Programmes should revise monitoring benchmarks and targets from less than 1000 copies per mL to less than 50 copies per mL to strengthen clinical outcomes and track progress to epidemic control.

FUNDING

None.

Low-level viraemia: An emerging concern among people living with HIV in Uganda and across sub-Saharan Africa

Attaining viral load (VL) suppression for over 95% of the people living with HIV on antiretroviral therapy is a fundamental step in enabling Uganda and other sub-Saharan African countries to achieve global Sustainable Development Goal targets to end the HIV/AIDS epidemic by 2030. In line with the 2013 World Health Organization recommendations, several sub-Saharan African countries, including Uganda, use a threshold of 1000 HIV viral RNA copies/mL to determine HIV viral non-suppression. The United States Centers for Disease Control and Prevention and the International Association of Providers of AIDS Care deem this threshold very high, and hence recommend using 200 copies/mL to determine viral non-suppression. Using 1000 copies/mL as a threshold ignores people living with HIV who have low-level viraemia (LLV; HIV VL of at least 50 copies/mL but less than 1000 copies/mL). Despite the 2021 World Health Organization recommendations of using intensive adherence counselling for people living with HIV with LLV, several sub-Saharan African countries have no interventions to address LLV. However, recent studies have associated LLV with increased risks of HIV drug resistance, virologic failure and transmission. The purpose of this narrative review is to provide insights on the emerging concern of LLV among people living with HIV receiving antiretroviral therapy in sub-Saharan Africa. The review also provides guidance for Uganda and other sub-Saharan African countries to implement immediate appropriate interventions like intensive adherence counselling, reducing VL thresholds for non-suppression and conducting more research to manage LLV which threatens progress towards ending HIV by 2030.

Men who have sex with men is the high-risk drug resistance population: A meta-analysis of HIV-1 drug resistance profiles and trends in China

WHAT IS KNOWN AND OBJECTIVE

Except for the transmitted drug resistance (TDR)'s standard sampling and monitoring protocol, China's HIV-1 pretreatment drug resistance (PDR) and acquired drug resistance (ADR) results vary widely due to the studies' diverse background. This meta-analysis was conducted to comprehensively understand the drug resistance profiles of Chinese HIV/AIDS patients and compare the drug resistance differences among groups to provide a reference for the further improvement of treatment protocols.

METHODS

Data sources for this study were WANFANG, VIP, CNKI, SinoMed, PubMed and Web of Science databases from January 1, 2010 to January 13, 2022. Data extracted from the literature were analyzed by R and Stata to evaluate the profile and changing trend of drug resistance in Chinese HIV/AIDS patients.

RESULTS AND DISCUSSION

One hundred twenty-one literature were included. The combined PDR and ADR in the Chinese HIV/AIDS patients was 5.56% (95% CI: 4.77%-6.41%) and 51.33% (95% CI: 47.57%-55.38%), respectively. The time trend analysis shows the upward trend of PDR. There were significate differences in ADR among different sample sources, the ADR in the central region were higher than those in all other regions. The PDR in men who have sex with men (MSM) was lower the whole population, while the MSM's ADR was much higher than whole population.

WHAT IS NEW AND CONCLUSION

PDR in China showed an upward trend and exceeded the 5% warning line but is still at a low level worldwide. ADR is stable and below the middle level globally; the comprehensively promoted free ART in China still has lasting effects. MSM is the high-risk drug resistance population, targeted treatment strategies should be used.

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.

Impact of low-level viremia with drug resistance on CD4 cell counts among people living with HIV on antiretroviral treatment in China

Background

Maintaining plasma HIV RNA suppression below the limit of quantification is the goal of antiretroviral therapy (ART). When viral loads (VL) remain in low-level viremia (LLV), or between 201 and 999 copies/mL, the clinical consequences are still not clear. We investigated the occurrence of LLV with drug resistance and its effect on CD4 cell counts in a large Chinese cohort.

Methods

We analysed data of 6,530 ART-experienced patients (42.1 ± 10.9 years; 37.3% female) from the China’s national HIV drug resistance (HIVDR) surveillance database. Participants were followed up for 32.9 (IQR 16.7–50.5) months. LLV was defined as the occurrence of at least one viral load (VL) measurement of 50–200 copies/mL during ART. Outcomes were drug resistance associated mutations (DRAM) and CD4 cell counts levels.

Results

Among 6530 patients, 58.0% patients achieved VL less than 50 copies/mL, 27.8% with VL between 50 and 999 copies/mL (8.6% experienced LLV), and 14.2% had a VL ≥ 1000 copies/mL. Of 1818 patients with VL 50–999 copies/mL, 182 (10.0%) experienced HIVDR, the most common DRAM were M184I/V 28.6%, K103N 19.2%, and V181C/I/V 10.4% (multidrug resistance: 27.5%), and patients with HIVDR had a higher risk of CD4 cell counts < 200 cells/μL (AOR 3.8, 95% CI 2.6–5.5, p < 0.01) comparing with those without HIVDR. Of 925 patients with VL ≥ 1000 copies/mL, 495 (53.5%) acquired HIVDR, the most common DRAM were K103N 43.8%, M184I/V 43.2%, M41L 19.0%, D67N/G 16.4%, V181C/I/V 14.5%, G190A/S 13.9% and K101E 13.7% (multidrug resistance: 75.8%), and patients with HIVDR had a higher risk of CD4 cell counts < 200 cells/μL (AOR 5.8, 95% CI 4.6–7.4, p < 0.01) comparing with those without HIVDR.

Conclusion

Persistent with VL 50–999 copies/mL on ART is associated with emerging DRAM for all drug classes, and patients in this setting were at increased risk of CD4 cell counts < 200 cells/μL, which suggest resistance monitoring and ART optimization be earlier considered.

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.

Predictors of low-level HIV viraemia and virological failure in the era of integrase inhibitors: A Spanish nationwide cohort

OBJECTIVES

To pinpoint factors associated with low-level viraemia (LLV) and virological failure (VF) in people living with HIV in the era of high-efficacy antiretroviral treatment (ART) and widespread use of integrase strand transfer inhibitor (INSTIs)-based ART.

METHODS

We included adults aged > 18 years starting their first ART between 2015 and 2018 in the Spanish HIV/AIDS Research Network National Cohort (CoRIS). Low-level viraemia was defined as plasma viral load (pVL) of 50-199 copies/mL at weeks 48 and 72 and VF was defined as pVL ≥ 50 copies/mL at week 48 and pVL ≥ 200 copies/mL at week 72. Multivariable logistic regression models assessed the impact on LLV and VF of baseline CD4 T-cell count, CD4/CD8 T-cell ratio and pVL, initial ART classes, age at ART initiation, time between HIV diagnosis and ART initiation, gender and transmission route.

RESULTS

Out of 4186 participants, 3120 (76.0%) started INSTIs, 455 (11.1%) started boosted protease inhibitors (bPIs) and 443 (10.8%) started nonnucleoside reverse transcriptase inhibitors (NNRTIs), either of them with two nucleos(t)ide reverse transcriptase inhibitors (NRTIs). Low-level viraemia was met in 2.5% of participants and VF in 4.3%. There were no significant differences throughout the years for both virological outcomes. Baseline HIV-1 RNA > 5 log₁₀ copies/mL was the only consistent predictor of higher risk of LLV [adjusted odds ratio (aOR) = 9.8, 95% confidence interval (CI): 2.0-48.3] and VF (aOR = 5.4, 95% CI: 1.9-15.1), even in participants treated with INSTIs.

CONCLUSIONS

The rates of LLV and VF were low but remained steady throughout the years. Baseline HIV-1 RNA > 5 log₁₀ copies/mL showed a persistent association with LLV and VF even in participants receiving INSTIs.

HIV-1 Treatment Failure, Drug Resistance, and Clinical Outcomes in Perinatally Infected Children and Adolescents Failing First-Line Antiretroviral Therapy in Western Kenya

BACKGROUND

Long-term impact of drug resistance in perinatally infected children and adolescents living with HIV (CALWH) is poorly understood. We determined drug resistance and examined its long-term impact on failure and mortality in Kenyan CALWH failing first-line non-nucleoside reverse transcriptase inhibitor-based antiretroviral therapy (ART).

SETTING

Academic Model Providing Access to Healthcare, western Kenya.

METHODS

Participants were enrolled in 2010-2013 (timepoint 1) and a subsample re-enrolled after 4-7 years (timepoint 2). Viral load (VL) was performed on timepoint 1 samples, with genotyping of those with detectable VL. Primary endpoints were treatment failure (VL >1000 copies/mL) at and death before timepoint 2. Multinomial regression analysis was used to characterize resistance effect on death, failure, and loss-to-follow-up, adjusting for key variables.

RESULTS

The initial cohort (n = 480) was 52% (n = 251) female, median age 8 years, median CD4% 31%, 79% (n = 379) on zidovudine/abacavir + lamivudine + efavirenz/nevirapine for median 2 years. Of these, 31% (n = 149) failed at timepoint 1. Genotypes at timepoint 1, available on n = 128, demonstrated 93% (n = 119) extensive resistance, affecting second line. Of 128, 22 failed at timepoint 2, 17 died, and 32 were lost to follow-up before timepoint 2. Having >5 resistance mutations at timepoint 1 was associated with higher mortality [relative risk ratio (RRR) = 8.7, confidence interval (CI) 2.1 to 36.3] and loss to follow-up (RRR = 3.2, CI 1.1 to 9.2). Switching to second line was associated with lower mortality (RRR <0.05, CI <0.05 to 0.1) and loss to follow-up (RRR = 0.1, CI <0.05 to 0.3).

CONCLUSION

Extensive resistance and limited switch to second line in perinatally infected Kenyan CALWH failing first-line ART were associated with long-term failure and mortality. Findings emphasize urgency for interventions to sustain effective, life-long ART in this vulnerable population.

Persistent low-Level viremia in persons living with HIV undertreatment: An unresolved status

Antiretroviral therapy (ART) allows suppressed viremia to reach less than 50 copies/mL in most treated persons living with HIV (PLWH). However, the existence of PLWH that show events of persistent low-level viremia (pLLV) between 50 and 1000 copies/mL and with different virological consequences have been observed. PLLV has been associated with higher virological failure (VF), viral genotype resistance, adherence difficulties and AIDS events. Moreover, some reports show that pLLV status can lead to residual immune activation and inflammation, with an increased risk of immunovirological failure and a pro-inflammatory cytokine level which can lead to a higher occurrence of non-AIDS defining events (NADEs) and other adverse clinical outcomes. Until now, however, published data have shown controversial results that hinder understanding of the true cause(s) and origin(s) of this phenomenon. Molecular mechanisms related to viral reservoir size and clonal expansion have been suggested as the possible origin of pLLV. This review aims to assess recent findings to provide a global view of the role of pLLV in PLWH and the impact this status may cause on the clinical progression of these patients.

Viral Load Status Before Switching to Dolutegravir-Containing Antiretroviral Therapy and Associations With Human Immunodeficiency Virus Treatment Outcomes in Sub-Saharan Africa

BACKGROUND

Dolutegravir is being rolled out globally as part of preferred antiretroviral therapy (ART) regimens, including among treatment-experienced patients. The role of viral load (VL) testing before switching patients already on ART to a dolutegravir-containing regimen is less clear in real-world settings.

METHODS

We included patients from the International epidemiology Databases to Evaluate AIDS consortium who switched from a nevirapine- or efavirenz-containing regimen to one with dolutegravir. We used multivariable cause-specific hazards regression to estimate the association of the most recent VL test in the 12 months before switching with subsequent outcomes.

RESULTS

We included 36 393 patients at 37 sites in 5 countries (Democratic Republic of the Congo, Kenya, Rwanda, Tanzania, Uganda) who switched to dolutegravir from July 2017 through February 2020, with a median follow-up of approximately 11 months. Compared with those who switched with a VL <200 copies/mL, patients without a recent VL test or with a preswitch VL ≥1000 copies/mL had significantly increased hazards of an incident VL ≥1000 copies/mL (adjusted hazard ratio [aHR], 2.89; 95% confidence interval [CI], 1.99-4.19 and aHR, 6.60; 95% CI, 4.36-9.99, respectively) and pulmonary tuberculosis or a World Health Organization clinical stage 4 event (aHR, 4.78; 95% CI, 2.77-8.24 and aHR, 13.97; 95% CI, 6.62-29.50, respectively).

CONCLUSIONS

A VL test before switching to dolutegravir may help identify patients who need additional clinical monitoring and/or adherence support. Further surveillance of patients who switched to dolutegravir with an unknown or unsuppressed VL is needed.

Feasibility and clinical relevance of HIV-1 drug resistance testing in patients with low-level viraemia in South Africa

OBJECTIVES

To determine the feasibility of HIV genotyping at low-level viraemia (LLV) using an in-house assay in a South African population and the prevalence, as well as the clinical relevance, of drug resistance (HIVDR) in this population.

METHODS

We conducted an observational, retrospective, cohort study on patient samples with LLV referred for routine HIVDR testing at a public sector Johannesburg laboratory from August 2017 to October 2018. Genotyping was performed using a nested RT-PCR assay and Sanger sequencing. The genotyping success rate was evaluated for different viraemia categories. Sequences were loaded onto the Stanford HIVdb genotypic resistance tool (version 8.7) for drug resistance interpretation.

RESULTS

Plasma samples from 159 HIV-1-infected, treatment-experienced adults with LLV (5-999 copies/mL) were analysed. The in-house assay performed well with an overall success rate of 78.6% (125/159, 95% CI 71.6-84.3). The prevalence of drug resistance mutations in the LLV cohort was 79.2% (99/125, 95% CI 71.2-85.4) with most patients (n = 109, 68.6%) on a PI-based regimen at the time of genotyping. Of 125 sequences obtained, 73.6% (92/125) had ≥1 NRTI mutation while 70.4% (88/125) had ≥1 NNRTI mutation. Major PI mutations, including M46I and V82A, were detected in 7.2% (9/125) of patients.

CONCLUSIONS

Current South African virological failure guidelines may keep patients on failing regimens for longer than necessary. Our data suggest that genotyping at LLV is feasible and implementation could result in earlier identification and referral of patients requiring third-line regimens.

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.

Impact of genotypic diversity on selection of subtype-specific drug resistance profiles during raltegravir-based therapy in individuals infected with B and BF recombinant HIV-1 strains

BACKGROUND

Current knowledge on HIV-1 resistance to integrase inhibitors (INIs) is based mostly on subtype B strains. This contrasts with the increasing use of INIs in low- and middle-income countries, where non-B subtypes predominate.

MATERIALS AND METHODS

HIV-1 drug resistance genotyping was performed in 30 HIV-1-infected individuals undergoing virological failure to raltegravir. Drug resistance mutations (DRMs) and HIV-1 subtype were characterized using Stanford HIVdb and phylogenetic analyses.

RESULTS

Of the 30 integrase (IN) sequences, 14 were characterized as subtype F (47%), 8 as subtype B (27%), 7 as BF recombinants (23%) and 1 as a putative CRF05_DF (3%). In 25 cases (83%), protease and reverse transcriptase (PR-RT) sequences from the same individuals confirmed the presence of different BF recombinants. Stanford HIVdb genotyping was concordant with phylogenetic inference in 70% of IN and 60% of PR-RT sequences. INI DRMs differed between B and F IN subtypes, with Q148K/R/H, G140S and E138K/A being more prevalent in subtype B (63% versus 0%, P = 0.0021; 50% versus 0%, P = 0.0096; and 50% versus 0%, P = 0.0096, respectively). These differences were independent of the time on raltegravir therapy or viral load at the time of genotyping. INI DRMs in subtype F IN genomes predicted a lower level of resistance to raltegravir and no cross-resistance to second-generation INIs.

CONCLUSIONS

Alternative resistance pathways to raltegravir develop in subtypes B and F IN genomes, with implications for clinical practice. Evaluating the role of HIV-1 subtype in development and persistence of mutations that confer resistance to INIs will be important to improve algorithms for resistance testing and optimize the use of INIs.

High level of HIV drug resistance informs dolutegravir roll-out and optimized NRTI backbone strategy in Mozambique

Background

HIV drug resistance (HIV-DR) is rising in sub-Saharan Africa in both ART-naive and ART-experienced patients.

Objectives

To estimate the level of acquired DR (ADR) and pre-treatment DR (PDR) across selected urban and rural sites in Southern Africa, in Mozambique.

Methods

We conducted two cross-sectional surveys among adult HIV patients (October 2017–18) assessing ADR and PDR. In the (ADR) survey, those on NNRTI-based first-line ART for ≥6 months were recruited (three sites). In the PDR survey, those ART-naive or experienced with ≥3 months of treatment interruption prior were enrolled (eight sites).

Results

Among 1113 ADR survey participants 83% were receiving tenofovir (TDF)/lamivudine (3TC)/efavirenz (EFV). The median time on ART was 4.5 years (Maputo) and 3.2 years (Tete), 8.3% (95% CI 6.2%-10.6%, Maputo) and 15.5% (Tete) had a VL ≥ 1000 copies/mL, among whom 66% and 76.4% had NNRTI+NRTI resistance, and 52.8% and 66.7% had 3TC+TDF-DR. Among those on TDF regimens, 31.1% (Maputo) and 42.2% (Tete) were still TDF susceptible, whereas 24.4% and 11.5% had TDF+zidovudine (ZDV)-DR. Among those on ZDV regimens, 25% and 54.5% had TDF+ZDV-DR. The PDR survey included 735 participants: NNRTI-PDR was 16.8% (12.0–22.6) (Maputo) and 31.2% (26.2–36.6) (Tete), with a higher proportion (≥50%) among those previously on ART affected by PDR.

Conclusions

In Mozambique, viral failure was driven by NNRTI and NRTI resistance, with NRTI DR affecting backbone options. NNRTI-PDR levels surpassed the WHO 10% ‘alert’ threshold. Replacing NNRTI first-line drugs is urgent, as is frequent viral load monitoring and resistance surveillance. Changing NRTI backbones when switching to second-line regimens may need reconsideration.

Substantial decline in heavily treated therapy-experienced persons with HIV with limited antiretroviral treatment options

OBJECTIVE

Historically, a high burden of resistance to antiretroviral therapy (ART) in heavily treatment-experienced (HTE) persons with HIV (PWH) resulted in limited treatment options (LTOs). We evaluated the prevalence, risk factors, and virologic control of HTE PWH with LTO throughout the modern ART era.

DESIGN

We examined all ART-experienced PWH in care between 2000 and 2017 in the Centers for AIDS Research Network of Integrated Clinical Systems cohort.

METHODS

We computed the annual prevalence of HTE PWH with LTO defined as having two or less available classes with two or less active drugs per class based on genotypic data and cumulative antiretroviral resistance. We used multivariable Cox proportional hazards models to examine risk of LTO by 3-year study entry periods adjusting for demographic and clinical characteristics.

RESULTS

Among 27 133 ART-experienced PWH, 916 were classified as having LTO. The prevalence of PWH with LTO was 5.2-7.5% in 2000-2006, decreased to 1.8% in 2007, and remained less than 1% after 2012. Persons entering the study in 2009-2011 had an 80% lower risk of LTO compared with those entering in 2006-2008 (adjusted hazard ratio 0.20; 95% confidence interval: 0.09-0.42). We found a significant increase in undetectable HIV viral loads among PWH ever classified as having LTO from less than 30% in 2001 to more than 80% in 2011, comparable with persons who never had LTO.

CONCLUSION

Results of this large multicenter study show a dramatic decline in the prevalence of PWH with LTO to less than 1% with the availability of more potent drugs and a marked increase in virologic suppression in the current ART era.

Genotype-Informed Versus Empiric Management Of VirEmia (GIVE MOVE): study protocol of an open-label randomised clinical trial in children and adolescents living with HIV in Lesotho and Tanzania

Background

Globally, the majority of people living with HIV have no or only limited access to HIV drug resistance testing to guide the selection of antiretroviral drugs. This is of particular concern for children and adolescents, who experience high rates of treatment failure. The GIVE MOVE trial assesses the clinical impact and cost-effectiveness of routinely providing genotypic resistance testing (GRT) to children and adolescents living with HIV who have an unsuppressed viral load (VL) while taking antiretroviral therapy (ART).

Methods

GIVE MOVE is an open-label randomised clinical trial enrolling children and adolescents (≥6 months to <19 years) living with HIV with a VL ≥400 copies/mL (c/mL) while taking first-line ART. Recruitment takes place at sites in Lesotho and Tanzania. Participants are randomised in a 1:1 allocation to a control arm receiving the standard of care (3 sessions of enhanced adherence counselling, a follow-up VL test, continuation of the same regimen upon viral resuppression or empiric selection of a new regimen upon sustained elevated viremia) and an intervention arm (GRT to inform onward treatment). The composite primary endpoint is the occurrence of any one or more of the following events during the 36 weeks of follow-up period: i) death due to any cause; ii) HIV- or ART-related hospital admission of ≥24 h duration; iii) new clinical World Health Organisation stage 4 event (excluding lymph node tuberculosis, stunting, oral or genital herpes simplex infection and oesophageal candidiasis); and iv) no documented VL <50 c/mL at 36 weeks follow-up. Secondary and exploratory endpoints assess additional health-related outcomes, and a nested study will assess the cost-effectiveness of the intervention. Enrolment of a total of 276 participants is planned, with an interim analysis scheduled after the first 138 participants have completed follow-up.

Discussion

This randomised clinical trial will assess if the availability of resistance testing improves clinical outcomes in children and adolescents with elevated viremia while taking ART.

Trial registration

This trial is registered with ClinicalTrials.gov (NCT04233242; registered 18.01.2020). More information: www.givemove.org.

Switch to second-line versus continued first-line antiretroviral therapy for patients with low-level HIV-1 viremia: An open-label randomized controlled trial in Lesotho

BACKGROUND

Current World Health Organization (WHO) antiretroviral therapy (ART) guidelines define virologic failure as two consecutive viral load (VL) measurements ≥1,000 copies/mL, triggering empiric switch to next-line ART. This trial assessed if patients with sustained low-level HIV-1 viremia on first-line ART benefit from a switch to second-line treatment.

METHODS AND FINDINGS

This multicenter, parallel-group, open-label, superiority, randomized controlled trial enrolled patients on first-line ART containing non-nucleoside reverse transcriptase inhibitors (NNRTI) with two consecutive VLs ≥100 copies/mL, with the second VL between 100-999 copies/mL, from eight clinics in Lesotho. Consenting participants were randomly assigned (1:1), stratified by facility, demographic group, and baseline VL, to either switch to second-line ART (switch group) or continued first-line ART (control group; WHO guidelines). The primary endpoint was viral suppression (<50 copies/mL) at 36 weeks. Analyses were by intention to treat, using logistic regression models, adjusted for demographic group and baseline VL. Between August 1, 2017, and August 7, 2019, 137 individuals were screened, of whom 80 were eligible and randomly assigned to switch (n = 40) or control group (n = 40). The majority of participants were female (54 [68%]) with a median age of 42 y (interquartile range [IQR] 35-51), taking tenofovir disoproxil fumarate/lamivudine/efavirenz (49 [61%]) and on ART for a median of 5.9 y (IQR 3.3-8.6). At 36 weeks, 22/40 (55%) participants in the switch versus 10/40 (25%) in the control group achieved viral suppression (adjusted difference 29%, 95% CI 8%-50%, p = 0.009). The switch group had significantly higher probability of viral suppression across different VL thresholds (<20, <100, <200, <400, and <600 copies/mL) but not for <1,000 copies/mL. Thirty-four (85%) participants in switch group and 21 (53%) in control group experienced at least one adverse event (AE) (p = 0.002). No hospitalization or death or other serious adverse events were observed. Study limitations include a follow-up period too short to observe differences in clinical outcomes, missing values in CD4 cell counts due to national stockout of reagents during the study, and limited generalizability of findings to other than NNRTI-based first-line ART regimens.

CONCLUSIONS

In this study, switching to second-line ART among patients with sustained low-level HIV-1 viremia resulted in a higher proportion of participants with viral suppression. These results endorse lowering the threshold for virologic failure in future WHO guidelines.

TRIAL REGISTRATION

The trial is registered at ClinicalTrials.gov, NCT03088241.

Very high pre-therapy viral load is a predictor of virological rebound in HIV-1-infected patients starting a modern first-line regimen

BACKGROUND

Pre-cART (combined antiretroviral therapy) plasma viral load >500,000 copies/ml has been associated with a lower probability of achieving virological suppression, while few data about its role on maintenance of virological suppression are available. In this study we aimed to clarify whether high levels of pre-cART viraemia are associated with virological rebound (VR) after virological suppression.

METHODS

HIV-infected individuals who achieved virological suppression after first-line cART were included. VR was defined as the first of two consecutive viraemia >50 copies/ml (VR50) or, in an alternative analysis, >200 copies/ml (VR200). The impact of pre-cART viraemia on the risk of VR was evaluated by survival analyses.

RESULTS

Among 5,766 patients included, 59.2%, 31.4%, 5.2% and 4.2% had pre-cART viraemia ≤100,000, 100,001-500,000, 500,001-1,000,000 and >1,000,000 copies/ml, respectively. Patients with pre-cART viraemia levels >1,000,000 copies/ml had the highest probability of VR (>1,000,000; 500,000-1,000,000; 100,000-500,000; <100,000 copies/ml; VR50: 28.4%; 24.3%; 17.6%; 13.8%, P<0.0001; VR200: 14.4%; 11.1%; 7.2%; 7.6%; P=0.009). By Cox multivariable analyses, patients with pre-cART viraemia >500,000 and >1,000,000 copies/ml showed a significantly higher risk of VR regardless of the VR end point used. No difference in the risk of VR was found between patients with pre-cART viraemia ranging 500,000-1,000,000 copies/ml and those with pre-cART viraemia >1,000,000 copies/ml, regardless of the VR end point used.

CONCLUSIONS

Pre-cART plasma viral load levels >500,000 copies/ml can identify fragile patients with poorer chance of maintaining virological control after an initial response. An effort in defining effective treatment strategies is mandatory for these patients that remain difficult to treat.

Tenofovir and emtricitabine resistance among antiretroviral-naive patients in the Canadian Observational Cohort Collaboration: implications for PrEP

BACKGROUND

The real-world effectiveness of pre-exposure prophylaxis (PrEP) may be influenced by circulating HIV strains resistant to either tenofovir or emtricitabine. Yet, few studies have examined rates of resistance to these drugs in clinical settings.

METHODS

We conducted a retrospective cohort study of antiretroviral-naive participants in the Canadian Observational Cohort collaboration who initiated antiretroviral therapy between 2006 and 2014. In separate analyses, we determined the prevalence of pretherapy resistance and cumulative incidence of follow-up resistance to tenofovir and emtricitabine. We used multivariable proportional hazards models to examine associations between baseline variables and the development of resistance.

RESULTS

We studied 6,622 antiretroviral-naive participants initiating therapy, of whom 5,428 (82.0%) had a baseline resistance test. Baseline resistance to tenofovir and emtricitabine was observed in 83 (1.5%) and 21 (0.4%) patients, respectively. Among patients without baseline resistance, the cumulative incidence of resistance to tenofovir and emtricitabine 5 years following treatment initiation was 0.0070 (95% CI 0.0046, 0.0095) and 0.033 (95% CI 0.028, 0.038), respectively. Following multivariable analysis, a baseline viral load ≥100,000 copies/ml was associated with emergence of tenofovir (hazard ratio [HR] 2.88; 95% CI 1.35, 6.15) and emtricitabine (HR 2.27; 95% CI 1.64, 3.15) resistance. Initiating an integrase inhibitor-based regimen and CD4⁺ T-cell count below 200 cells/mm³ were also associated with resistance to each drug.

CONCLUSIONS

We observed a low prevalence of baseline resistance and a low incidence of emergence of resistance to tenofovir and emtricitabine among antiretroviral-naive patients in routine clinical care.

Virological suppression and clinical management in response to viremia in South African HIV treatment program: A multicenter cohort study

BACKGROUND

Uptake of antiretroviral treatment (ART) is expanding rapidly in low- and middle-income countries (LMIC). Monitoring of virological suppression is recommended at 6 months of treatment and annually thereafter. In case of confirmed virological failure, a switch to second-line ART is indicated. There is a paucity of data on virological suppression and clinical management of patients experiencing viremia in clinical practice in LMIC. We report a large-scale multicenter assessment of virological suppression over time and management of viremia under programmatic conditions.

METHODS AND FINDINGS

Linked medical record and laboratory source data from adult patients on first-line ART at 52 South African centers between 1 January 2007 and 1 May 2018 were studied. Virological suppression, switch to second-line ART, death, and loss to follow-up were analyzed. Multistate models and Cox proportional hazard models were used to assess suppression over time and predictors of treatment outcomes. A total of 104,719 patients were included. Patients were predominantly female (67.6%). Median age was 35.7 years (interquartile range [IQR]: 29.9-43.0). In on-treatment analysis, suppression below 1,000 copies/mL was 89.0% at month 12 and 90.4% at month 72. Suppression below 50 copies/mL was 73.1% at month 12 and 77.5% at month 72. Intention-to-treat suppression was 75.0% and 64.3% below 1,000 and 50 copies/mL at month 72, respectively. Viremia occurred in 19.8% (20,766/104,719) of patients during a median follow-up of 152 (IQR: 61-265) weeks. Being male and below 35 years of age and having a CD4 count below 200 cells/μL prior to start of ART were risk factors for viremia. After detection of viremia, confirmatory testing took 29 weeks (IQR: 16-54). Viral resuppression to below 1,000 copies/mL without switch of ART occurred frequently (45.6%; 6,030/13,210) but was associated with renewed viral rebound and switch. Of patients with confirmed failure who remained in care, only 41.5% (1,872/4,510) were switched. The median time to switch was 68 weeks (IQR: 35-127), resulting in 12,325 person-years spent with a viral load above 1,000 copies/mL. Limitations of this study include potential missing data, which is in part addressed by the use of cross-matched laboratory source data, and the possibility of unmeasured confounding.

CONCLUSIONS

In this study, 90% virological suppression below the threshold of 1,000 copies/mL was observed in on-treatment analysis. However, this target was not met at the 50-copies/mL threshold or in intention-to-treat analysis. Clinical management in response to viremia was profoundly delayed, prolonging the duration of viremia and potential for transmission. Diagnostic tools to establish the cause of viremia are urgently needed to accelerate clinical decision-making.

Human Immunodeficiency Virus Drug Resistance: 2018 Recommendations of the International Antiviral Society-USA Panel

Background

Contemporary antiretroviral therapies (ART) and management strategies have diminished both human immunodeficiency virus (HIV) treatment failure and the acquired resistance to drugs in resource-rich regions, but transmission of drug-resistant viruses has not similarly decreased. In low- and middle-income regions, ART roll-out has improved outcomes, but has resulted in increasing acquired and transmitted resistances. Our objective was to review resistance to ART drugs and methods to detect it, and to provide updated recommendations for testing and monitoring for drug resistance in HIV-infected individuals.

Methods

A volunteer panel of experts appointed by the International Antiviral (formerly AIDS) Society–USA reviewed relevant peer-reviewed data that were published or presented at scientific conferences. Recommendations were rated according to the strength of the recommendation and quality of the evidence, and reached by full panel consensus.

Results

Resistance testing remains a cornerstone of ART. It is recommended in newly-diagnosed individuals and in patients in whom ART has failed. Testing for transmitted integrase strand-transfer inhibitor resistance is currently not recommended, but this may change as more resistance emerges with widespread use. Sanger-based and next-generation sequencing approaches are each suited for genotypic testing. Testing for minority variants harboring drug resistance may only be considered if treatments depend on a first-generation nonnucleoside analogue reverse transcriptase inhibitor. Different HIV-1 subtypes do not need special considerations regarding resistance testing.

Conclusions

Testing for HIV drug resistance in drug-naive individuals and in patients in whom antiretroviral drugs are failing, and the appreciation of the role of testing, are crucial to the prevention and management of failure of ART.

Determining virological suppression and resuppression by point-of-care viral load testing in a HIV care setting in sub-Saharan Africa

BACKGROUND

This prospective pilot study explored same-day point-of-care viral load testing in a setting in Ghana that has yet to implement virological monitoring of antiretroviral therapy (ART).

METHODS

Consecutive patients accessing outpatient care while on ART underwent HIV-1 RNA quantification by Xpert. Those with viraemia at the first measurement (T0) received immediate adherence counselling and were reassessed 8 weeks later (T1). Predictors of virological status were determined by logistic regression analysis. Drug resistance-associated mutations (RAMs) were detected by Sanger sequencing.

FINDINGS

At T0, participants had received treatment for a median of 8·9 years; 297/333 (89·2%) were on NNRTI-based ART. The viral load was ≥40 copies/mL in 164/333 (49·2%) patients and ≥1000 copies/mL in 71/333 (21·3%). In the latter group, 50/65 (76·9%) and 55/65 (84·6%) harboured NRTI and NNRTI RAMs, respectively, and 27/65 (41·5%) had ≥1 tenofovir RAM. Among 150/164 (91·5%) viraemic patients that reattended at T1, 32/150 (21·3%) showed resuppression <40 copies/mL, comprising 1/65 (1·5%) subjects with T0 viral load ≥1000 copies/mL and 31/85 (36·5%) subjects with lower levels. A T0 viral load ≥1000 copies/mL and detection of RAMs predicted ongoing T1 viraemia independently of self-reported adherence levels. Among participants with T0 viral load ≥1000 copies/mL, 23/65 (35·4%) showed resuppression <1000 copies/mL; the response was more likely among those with higher adherence levels and no RAMs.

INTERPRETATION

Same-day point-of-care viral load testing was feasible and revealed poor virological control and suboptimal resuppression rates despite adherence counselling. Controlled studies should determine optimal triaging modalities for same-day versus deferred viral load testing.

FUNDING

University of Liverpool, South Tees Infectious Diseases Research Fund.

Low-Level Viremia Is Associated With Clinical Progression in HIV-Infected Patients Receiving Antiretroviral Treatment

BACKGROUND

The objective of this study was to investigate the long-term impact of low-level viremia (LLV) on all-cause mortality, AIDS and non-AIDS events (NAEs), and virological failure in patients receiving antiretroviral therapy (ART).

METHODS

We analyzed ART-naive adults from the cohort of the Spanish AIDS Research Network (CoRIS) who initiated ART from 2004 to 2015 and achieved plasma viral load (VL) below 50 copies per milliliter. LLV50-199 was defined as 2 consecutive VL between 50 and 199 copies per milliliter, and LLV200-499 as 2 consecutive VL between 50 and 499 copies per milliliter with at least one between 200 and 499 copies per milliliter. Multivariable Cox models were used to estimate the association of LLV with AIDS events/death, non-AIDS events, and virological failure.

RESULTS

Of 5986 patients included, 237 (4.0%) experienced LLV50-199 and 168 (2.8%) developed LLV200-499. One hundred seventy-one patients died or developed an AIDS event, 245 had any serious NAE and 280 had virological failure. LLV200-499 was strongly associated with a higher risk of both AIDS events/death [adjusted hazard ratio (aHR), 2.89; 95% confidence interval (CI), 1.41 to 5.92] and virological failure (aHR, 3.25; 95% CI: 1.77 to 5.99), whereas no differences were observed between LLV50-199 and no LLV neither for AIDS events/death (aHR, 1.84; 95% CI: 0.89 to 3.82) nor virological failure (aHR, 1.42; 95% CI: 0.78 to 2.58). LLV was not associated with the occurrence of any serious NAE.

CONCLUSIONS

In this cohort, LLV200-499 was strongly associated with AIDS events/death and virological failure, but not with any serious NAE. Therefore, vigorous treatment should be implemented in patients with more than 200 copies per milliliter.

Impact of the M184V/I Mutation on the Efficacy of Abacavir/Lamivudine/Dolutegravir Therapy in HIV Treatment-Experienced Patients

Objective

The impact of the M184V/I mutation on the virological failure (VF) rate in HIV-positive patients with suppressed viremia switching to an abacavir/lamivudine/dolutegravir regimen has been poorly evaluated.

Method

This is an observational study from 5 European HIV cohorts among treatment-experienced adults with ≤50 copies/mL of HIV-1 RNA who switched to abacavir/lamivudine/dolutegravir. Primary outcome was the time to first VF (2 consecutive HIV-1 RNA >50 copies/mL or single HIV-1 RNA >50 copies/mL accompanied by change in antiretroviral therapy [ART]). We also analyzed a composite outcome considering the presence of VF and/or virological blips. We report also the results of an inverse probability weighting analysis on a restricted population with a prior history of VF on any ART regimen to calculate statistics standardized to the disparate sampling population.

Results

We included 1626 patients (median follow-up, 288.5 days; interquartile range, 154-441). Patients with a genotypically documented M184V/I mutation (n = 137) had a lower CD4 nadir and a longer history of antiviral treatment. The incidence of VF was 29.8 cases (11.2-79.4) per 1000 person-years in those with a previously documented M184V/I, and 13.6 cases (8.4-21.8) in patients without documented M184V/I. Propensity score weighting in a restricted population (n = 580) showed that M184V/I was not associated with VF or the composite endpoint (hazard ratio [HR], 1.27; 95% confidence interval [CI], 0.35-4.59 and HR 1.66; 95% CI, 0.81-3.43, respectively).

Conclusions

In ART-experienced patients switching to an abacavir/lamivudine/dolutegravir treatment, we observed few VFs and found no evidence for an impact of previously-acquired M184V/I mutation on this outcome. Additional analyses are required to demonstrate whether these findings will remain robust during a longer follow-up.

Validation of publicly-available software used in analyzing NGS data for HIV-1 drug resistance mutations and transmission networks in a Washington, DC, Cohort

The DC Cohort is an ongoing longitudinal observational study of persons living with HIV. To better understand HIV-1 drug resistance and potential transmission clusters among these participants, we performed targeted, paired-end next-generation sequencing (NGS) of protease, reverse transcriptase and integrase amplicons. We elected to use free, publicly-available software (HyDRA Web, Stanford HIVdb and HIV-TRACE) for data analyses so that laboratory personnel without extensive bioinformatics expertise could use it; making the approach accessible and affordable for labs worldwide. With more laboratories transitioning away from Sanger-based chemistries to NGS platforms, lower frequency drug resistance mutations (DRMs) can be detected, yet their clinical relevance is uncertain. We looked at the impact choice in cutoff percentage had on number of DRMs detected and found an inverse correlation between the two. Longitudinal studies will be needed to determine whether low frequency DRMs are an early indicator of emerging resistance. We successfully validated this pipeline against a commercial pipeline, and another free, publicly-available pipeline. RT DRM results from HyDRA Web were compared to both SmartGene and PASeq Web; using the Mantel test, R2 values were 0.9332 (p<0.0001) and 0.9097 (p<0.0001), respectively. PR and IN DRM results from HyDRA Web were then compared with PASeq Web only; using the Mantel test, R2 values were 0.9993 (p<0.0001) and 0.9765 (p<0.0001), respectively. Drug resistance was highest for the NRTI drug class and lowest for the PI drug class in this cohort. RT DRM interpretation reports from this pipeline were also highly correlative compared to SmartGene pipeline; using the Spearman's Correlation, rs value was 0.97757 (p<0.0001). HIV-TRACE was used to identify potential transmission clusters to better understand potential linkages among an urban cohort of persons living with HIV; more individuals were male, of black race, with an HIV risk factor of either MSM or High-risk Heterosexual. Common DRMs existed among individuals within a cluster. In summary, we validated a comprehensive, easy-to-use and affordable NGS approach for tracking HIV-1 drug resistance and identifying potential transmission clusters within the community.

Patterns of detectable viraemia among children and adults with HIV infection taking antiretroviral therapy in Zimbabwe

OBJECTIVE

To investigate the incidence and predictors of viraemia among individuals on antiretroviral therapy (ART) in Harare, Zimbabwe.

METHODS

Children (0-19 years) and adults (>19 years) starting ART between 2013 and 2015 were followed for a median of 2.8 and 2.7 years, respectively. The incidence rates of virological failure (VF), low-level viraemia (LLV), and viral blips were assessed and the predictors of viraemia were determined using logistic and parametric survival regression analyses.

RESULTS

A total of 630 individuals initiated ART, and 19.7% of children and 5.6% of adults did not achieve viral suppression by 12 months. Younger age and CD4 count ≤200 cells/mm3 at baseline were associated with not being virally suppressed at 12 months in adults. Among those who achieved viral suppression during the follow-up period, the incidence of VF was higher in children (4.0/100 person-years vs. 0.4/100 person-years in adults; p<0.001), as was the incidence of LLV (1.9/100 person-years vs. 0.3/100 person-years in adults; p=0.03). The incidence rate of blips was 10.9 per 100 person-years in children and 4.0 per 100 person-years in adults.

CONCLUSIONS

Children are less likely to reach viral suppression and are at higher risk of viraemia while on ART than adults. The significance of LLV and blips needs further study.

HIV-1 second-line failure and drug resistance at high-level and low-level viremia in Western Kenya

OBJECTIVE

Characterize failure and resistance above and below guidelines-recommended 1000 copies/ml virologic threshold, upon second-line failure.

DESIGN

Cross-sectional study.

METHODS

Kenyan adults on lopinavir/ritonavir-based second-line were enrolled at AMPATH (Academic Model Providing Access to Healthcare). Charts were reviewed for demographic/clinical characteristics and CD4/viral load were obtained. Participants with detectable viral load had a second visit and pol genotyping was attempted in both visits. Accumulated resistance was defined as mutations in the second, not the first visit. Low-level viremia (LLV) was detectable viral load less than 1000 copies/ml. Failure and resistance associations were evaluated using logistic and Poisson regression, Fisher Exact and t-tests.

RESULTS

Of 394 participants (median age 42, 60% women, median 1.9 years on second-line) 48% had detectable viral load; 21% had viral load more than 1000 copies/ml, associated with younger age, tuberculosis treatment, shorter time on second-line, lower CD4count/percentage, longer first-line treatment interruption and pregnancy. In 105 sequences from the first visit (35 with LLV), 79% had resistance (57% dual-class, 7% triple-class; 46% with intermediate-to-high-level resistance to ≥1 future drug option). LLV was associated with more overall and NRTI-associated mutations and with predicted resistance to more next-regimen drugs. In 48 second-visit sequences (after median 55 days; IQR 28-33), 40% accumulated resistance and LLV was associated with more mutation accumulation.

CONCLUSION

High resistance upon second-line failure exists at levels above and below guideline-recommended virologic-failure threshold, impacting future treatment options. Optimization of care should include increased viral load monitoring, resistance testing and third-line ART access, and consideration of lowering the virologic failure threshold, though this demands further investigation.

SESOTHO trial ("Switch Either near Suppression Or THOusand") - switch to second-line versus WHO-guided standard of care for unsuppressed patients on first-line ART with viremia below 1000 copies/mL: protocol of a multicenter, parallel-group, open-label, randomized clinical trial in Lesotho, Southern Africa

BACKGROUND

The World Health Organization (WHO) recommends viral load (VL) measurement as the preferred monitoring strategy for HIV-infected individuals on antiretroviral therapy (ART) in resource-limited settings. The new WHO guidelines 2016 continue to define virologic failure as two consecutive VL ≥1000 copies/mL (at least 3 months apart) despite good adherence, triggering switch to second-line therapy. However, the threshold of 1000 copies/mL for defining virologic failure is based on low-quality evidence. Observational studies have shown that individuals with low-level viremia (measurable but below 1000 copies/mL) are at increased risk for accumulation of resistance mutations and subsequent virologic failure. The SESOTHO trial assesses a lower threshold for switch to second-line ART in patients with sustained unsuppressed VL.

METHODS

In this multicenter, parallel-group, open-label, randomized controlled trial conducted in Lesotho, patients on first-line ART with two consecutive unsuppressed VL measurements ≥100 copies/mL, where the second VL is between 100 and 999 copies/mL, will either be switched to second-line ART immediately (intervention group) or not be switched (standard of care, according to WHO guidelines). The primary endpoint is viral resuppression (VL < 50 copies/mL) 9 months after randomization. We will enrol 80 patients, giving us 90% power to detect a difference of 35% in viral resuppression between the groups (assuming two-sided 5% alpha error). For our primary analysis, we will use a modified intention-to-treat set, with those lost to care, death, or crossed over considered failure to resuppress, and using logistic regression models adjusted for the prespecified stratification variables.

DISCUSSION

The SESOTHO trial challenges the current WHO guidelines, assessing an alternative, lower VL threshold for patients with unsuppressed VL on first-line ART. This trial will provide data to inform future WHO guidelines on VL thresholds to recommend switch to second-line ART.

TRIAL REGISTRATION

ClinicalTrials.gov ( NCT03088241 ), registered May 05, 2017.

Expansion of Viral Load Testing and the Potential Impact on Human Immunodeficiency Virus Drug Resistance

Increasing the volume, strengthening the quality, and proactively using data of human immunodeficiency virus (HIV) load testing are pivotal to limiting the threat of HIV drug resistance (HIVDR) accumulation,and allow for optimal case-based HIVDR surveillance. Triangulation of viral load (VL) and HIVDR testing data could be pursued to answer key questions and translate data and results for program and public policy. Identification of virologic failure and early management mitigates the greater risk of HIVDR. Routine VL monitoring and evaluation systems are necessary, and countries should consider reviewing system requirements, structural needs, and procedural and technical factors for the entire VL cascade, with special emphasis on post-test result use.

Effect of HIV-1 low-level viraemia during antiretroviral therapy on treatment outcomes in WHO-guided South African treatment programmes: a multicentre cohort study

BACKGROUND

Antiretroviral therapy (ART) that enables suppression of HIV replication has been successfully rolled out at large scale to HIV-positive patients in low-income and middle-income countries. WHO guidelines for these regions define failure of ART with a lenient threshold of viraemia (HIV RNA viral load ≥1000 copies per mL). We investigated the occurrence of detectable viraemia during ART below this threshold and its effect on treatment outcomes in a large South African cohort.

METHODS

In this observational cohort study, we included HIV-positive adults registered between Jan 1, 2007, and May 1, 2016, at 57 clinical sites in South Africa, who were receiving WHO-recommended ART regimens and viral load monitoring. Low-level viraemia was defined as the occurrence of at least one viral load measurement of 51-999 copies per mL during ART. Outcomes were WHO-defined virological failure (one or more viral load measurement of ≥1000 copies per mL) and switch to second-line ART. Risks were estimated with Cox proportional hazard models.

FINDINGS

70 930 patients were included in the analysis, of whom 67 644 received first-line ART, 1476 received second-line ART, and 1810 received both. Median duration of follow-up was 124 weeks (IQR 56-221) for patients on first-line ART and 101 weeks (IQR 51-178) for patients on second-line ART. Low-level viraemia occurred in 16 013 (23%) of 69 454 patients, with an incidence of 11·5 per 100 person-years of follow-up (95% CI 11·4-11·7), during first-line ART. Virological failure during follow-up occurred in 14 380 (22%) of 69 454 patients on first-line ART. Low-level viraemia was associated with increased hazards of virological failure (hazard ratio [HR] 2·6, 95% CI 2·5-2·8; p<0·0001) and switch to second-line ART (HR 5·2, 4·4-6·1; p<0·0001]) compared with virological suppression of less than 50 copies per mL. Risk of virological failure increased further with higher ranges and persistence of low-level viraemia.

INTERPRETATION

In this large cohort, low-level viraemia occurred frequently and increased the risk of virological failure and switch to second-line ART. Strategies for management of low-level viraemia need to be incorporated into WHO guidelines to meet UNAIDS-defined targets aimed at halting the global HIV epidemic.

FUNDING

None.