HIV drug resistance in low-income and middle-income countries

Virological impact of HIV drug-resistance testing in children, adolescents, and adults failing first-line ART in Tanzania

BACKGROUND

Prospective data on the effectiveness of resistance testing in informing treatment decisions and outcomes in with first-line failure in these settings is limited. This study aimed to assess the virological impact of HIV drug-resistance testing in patients with virological failure in Tanzania.

METHODS

Participants were randomly assigned to either the control or the experimental group. In addition to the standard of care, patients in the experimental group had access to genotypic drug-resistance testing, information used during treatment change, and were followed up at six-and 12-months to determine virological suppression.

RESULTS

A total of 261 patients with a median age of 32 (14.7-44.7) years were enrolled. In the intention-to-treat analysis, at 6-months, suppression was achieved in 58 (42.3%; 95% CI, 34.1-50.1) experimental group patients versus 51 (41.1%; 95% CI, 32.5-49.8) control group patients, with a p-value of 0.4. At-12 months, suppression was achieved in 110 (80.3%; 95% CI, 73.6-87) experimental patients versus 99 (79.8%; 95% CI, 72.8-86.9) control patients, with a p-value of 0.5. In the per-protocol analysis, at 6-months, suppression was observed in 38.46% (95% CI, 27.6-49.3) experimental patients versus 38.6% (95% CI, 26.0-51.2) control patients, with a p-value of 0.5. At 12-months, suppression was observed in 79.49% (95% CI, 70.5-88.5) of experimental patients versus 75.44% (95% CI, 64.3-86.6) of control patients, with a p-value of 0.3.

CONCLUSION

Conducting HIV drug-resistance testing, and switch to individualised second-line regimens did not significantly improve virological suppression in patients experiencing first-line ART failure in Tanzania.

HIV-1 subtype-specific drug resistance on dolutegravir-based antiretroviral therapy: protocol for a multicentre study (DTG RESIST)

INTRODUCTION

HIV drug resistance poses a challenge to the United Nation's goal of ending the HIV/AIDS epidemic. The integrase strand transfer inhibitor (InSTI) dolutegravir, which has a higher resistance barrier, was endorsed by the WHO in 2019 for first-line, second-line and third-line antiretroviral therapy (ART). This multiplicity of roles of dolutegravir in ART may facilitate the emergence of dolutegravir resistance.

METHODS AND ANALYSIS

Nested within the International epidemiology Databases to Evaluate AIDS (IeDEA), DTG RESIST is a multicentre study of adults and adolescents living with HIV in sub-Saharan Africa, Asia, and South and Central America who experienced virological failure on dolutegravir-based ART. At the time of virological failure, whole blood will be collected and processed to prepare plasma or dried blood spots. Laboratories in Durban, Mexico City and Bangkok will perform genotyping. Analyses will focus on (1) individuals who experienced virological failure on dolutegravir and (2) those who started or switched to such a regimen and were at risk of virological failure. For population (1), the outcome will be any InSTI drug resistance mutations, and for population (2) virological failure is defined as a viral load >1000 copies/mL. Phenotypic testing will focus on non-B subtype viruses with major InSTI resistance mutations. Bayesian evolutionary models will explore and predict treatment failure genotypes. The study will have intermediate statistical power to detect differences in resistance mutation prevalence between major HIV-1 subtypes; ample power to identify risk factors for virological failure and limited power for analysing factors associated with individual InSTI drug resistance mutations.

ETHICS AND DISSEMINATION

The research protocol was approved by the Biomedical Research Ethics Committee at the University of KwaZulu-Natal, South Africa and the Ethics Committee of the Canton of Bern, Switzerland. All sites participate in International epidemiology Databases to Evaluate AIDS and have obtained ethics approval from their local ethics committee to collect additional data.

TRIAL REGISTRATION NUMBER

NCT06285110.

Impact of Low-Frequency Human Immunodeficiency Virus Type 1 Drug Resistance Mutations on Antiretroviral Therapy Outcomes

BACKGROUND

The association between low-frequency human immunodeficiency virus type 1 (HIV-1) drug resistance mutations (DRMs) and treatment failure (TF) is controversial. We explore this association using next-generation sequencing (NGS) methods that accurately sample low-frequency DRMs.

METHODS

We enrolled women with HIV-1 in Malawi who were either antiretroviral therapy (ART) naive (cohort A), had ART failure (cohort B), or had discontinued ART (cohort C). At entry, cohorts A and C began a nonnucleoside reverse transcriptase inhibitor-based regimen and cohort B started a protease inhibitor-based regimen. We used Primer ID MiSeq to identify regimen-relevant DRMs in entry and TF plasma samples, and a Cox proportional hazards model to calculate hazard ratios (HRs) for entry DRMs. Low-frequency DRMs were defined as ≤20%.

RESULTS

We sequenced 360 participants. Cohort B and C participants were more likely to have TF than cohort A participants. The presence of K103N at entry significantly increased TF risk among A and C participants at both high and low frequency, with HRs of 3.12 (95% confidence interval [CI], 1.58-6.18) and 2.38 (95% CI, 1.00-5.67), respectively. At TF, 45% of participants showed selection of DRMs while in the remaining participants there was an apparent lack of selective pressure from ART.

CONCLUSIONS

Using accurate NGS for DRM detection may benefit an additional 10% of patients by identifying low-frequency K103N mutations.

Performance of the Applied Biosystems HIV-1 Genotyping Kit with Integrase

HIV genotyping is used to assess HIV susceptibility to antiretroviral drugs. The Applied Biosystems HIV-1 Genotyping Kit with Integrase (AB kit, Thermo Fisher Scientific) detects resistance-associated mutations (RAMs) in HIV protease (PR), reverse transcriptase (RT), and integrase (IN). We compared results from the AB kit with results obtained previously with the ViroSeq HIV-1 Genotyping System. DNA amplicons from the AB kit were also analyzed using next-generation sequencing (NGS). HIV RNA was extracted using the MagNA Pure 24 instrument (Roche Diagnostics; 96 plasma samples, HIV subtype B, viral load range: 530-737,741 copies/mL). FASTA files were generated from AB kit data using Exatype (Hyrax Biosciences). DNA amplicons from the AB kit were also analyzed by NGS using the Nextera XT kit (Illumina). Drug resistance was predicted using the Stanford HIV Drug Resistance Database. The mean genetic distance for sequences from ViroSeq and the AB kit was 0.02% for PR/RT and 0.04% for IN; 103 major RAMs were detected by both methods. Four additional major RAMs were detected by the AB kit only. These four major RAMs were also detected by NGS (detected in 18.1%-38.2% of NGS reads). NGS detected 27 major RAMs that were not detected with either of the Sanger sequencing-based kits. All major RAMs detected with ViroSeq were detected with the AB kit; additional RAMs were detected with the AB kit only. DNA amplicons from the AB kit can be used for NGS for more sensitive detection of RAMs.

Ex vivo sensitivity to broadly neutralizing antibodies and anti-CD4 antibody UB-421 of infectious viral isolates from people living with multidrug-resistant HIV

BACKGROUND

People living with HIV (PLWH) with multidrug-resistant (MDR) viruses have limited therapeutic options and present challenges regarding clinical management. Recent studies have shown that passive transfer of combination broadly neutralizing antibodies (bNAbs) against HIV and anti-domain 1 CD4 antibody UB-421 can sustain virologic suppression in PLWH in the absence of antiretroviral therapy (ART). Yet studies addressing the therapeutic potential of these antibodies and/or detailed characterization of immunologic and virologic parameters in PLWH with MDR HIV are lacking.

METHODS

We examined levels of immune activation and exhaustion markers on CD8+ T cells and the intact HIV proviral DNA burden in 11 PLWH with MDR viruses. For comparison purposes, we included a control group consisting of 27 ART-naïve viremic PLWH. In addition, we determined the sensitivity of infectious viral isolates obtained from the participants against eight bNAbs (3BNC117, 10-1074, VRC01, VRC07, N6, 10E8, PGDM1400, and PGT121) and two anti-CD4 antibodies (ibalizumab and UB-421) using a TZM-bl-based neutralization/suppression assay.

FINDINGS

The level of intact HIV proviral DNA was comparable between the two groups (P = 0.29). The levels of activation and exhaustion markers PD-1 (P = 0.0019), TIGIT (P = 0.0222), 2B4 (P = 0.0015), CD160 (P = 0.0015), and CD38+/HLA-DR+ (P = 0.0138) were significantly lower in the MDR group. The infectious viral isolates from each study participant with MDR HIV were resistant to at least 2 bNAbs; however, they were sensitive to at least one of the CD4-binding and non-CD4-binding site antibodies. The majority of participants had ibalizumab-sensitive viruses although the isolates from some participants showed reduced sensitivity to ibalizumab. Notably, none of the 93 viral isolates obtained from the participants were resistant to UB-421.

INTERPRETATION

Our data suggest that combination therapy with HIV-specific bNAbs and/or UB-421 in the presence of optimized background therapy could potentially provide sustained virologic suppression in PLWH with MDR HIV. However, this therapeutic strategy needs to be evaluated in human clinical trials.

FUNDING

Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health.

HIV-1 subtype-specific drug resistance on dolutegravir-based antiretroviral therapy: protocol for a multicentre longitudinal study (DTG RESIST)

Introduction

HIV drug resistance poses a challenge to the United Nation's goal of ending the HIV/AIDS epidemic. The integrase strand transfer inhibitor (InSTI) dolutegravir, which has a higher resistance barrier, was endorsed by the World Health Organization in 2019 for first-, second-, and third-line antiretroviral therapy (ART). This multiplicity of roles of dolutegravir in ART may facilitate the emergence of dolutegravir resistance.

Methods and analysis

DTG RESIST is a multicentre longitudinal study of adults and adolescents living with HIV in sub-Saharan Africa, Asia, and South and Central America who experienced virologic failure on dolutegravir-based ART. At the time of virologic failure whole blood will be collected and processed to prepare plasma or dried blood spots. Laboratories in Durban, Mexico City and Bangkok will perform genotyping. Analyses will focus on (i) individuals who experienced virologic failure on dolutegravir, and (ii) on those who started or switched to such a regimen and were at risk of virologic failure. For population (i), the outcome will be any InSTI drug resistance mutations, and for population (ii) virologic failure defined as a viral load >1000 copies/mL. Phenotypic testing will focus on non-B subtype viruses with major InSTI resistance mutations. Bayesian evolutionary models will explore and predict treatment failure genotypes. The study will have intermediate statistical power to detect differences in resistance mutation prevalence between major HIV-1 subtypes; ample power to identify risk factors for virologic failure and limited power for analysing factors associated with individual InSTI drug resistance mutations.

Ethics and dissemination

The research protocol was approved by the Biomedical Research Ethics Committee at the University of KwaZulu-Natal, South Africa, and the Ethics Committee of the Canton of Bern, Switzerland. All sites participate in IeDEA and have obtained ethics approval from their local ethics committee to conduct the additional data collection.

Registration

NCT06285110.

Strengths and limitations of this study

- DTG RESIST is a large international study to prospectively examine emergent dolutegravir resistance in diverse settings characterised by different HIV-1 subtypes, provision of ART, and guidelines on resistance testing. - Embedded within the International epidemiology Databases to Evaluate AIDS (IeDEA), DTG RESIST will benefit from harmonized clinical data across participating sites and expertise in clinical, epidemiological, biological, and computational fields. - Procedures for sequencing and assembling genomes from different HIV-1 strains will be developed at the heart of the HIV epidemic, by the KwaZulu-Natal Research Innovation and Sequencing Platform (KRISP), in Durban, South Africa. Phenotypic testing, Genome Wide Association Study (GWAS) methods and Bayesian evolutionary models will explore and predict treatment failure genotypes. - A significant limitation is the absence of genotypic resistance data from participants before they started dolutegravir treatment, as collecting and bio-banking pre-treatment samples was not feasible at most IeDEA sites. Consistent and harmonized data on adherence to treatment are also lacking. - The distribution of HIV-1 subtypes across different sites is uncertain, which may limit the statistical power of the study in analysing patterns and risk factors for dolutegravir resistance. The results from GWAS and Bayesian modelling analyses will be preliminary and hypothesis-generating.

Viremia and HIV Drug Resistance Among People Receiving Dolutegravir Versus Efavirenz-Based First-Line Antiretroviral Therapy

Supplemental Digital Content is Available in the Text.

Major Drug Resistance Mutations on Reverse Transcriptase Gene in Human Immunodeficiency Virus Type-1 in Indonesia: A Systematic Review

PURPOSE OF REVIEW

The prevalence of HIV-1 in Indonesia is on a concerning upward trajectory, with a concurrent rise in the development of drug-resistant strains, challenging the efficacy of antiretroviral therapy (ART). Many mutations have been found in the pol gene that makes HIV resistant to ART. We aim to review the major drug resistance mutations (DRMs) of reverse transcriptase (RT) of pol gene in HIV-1 cases in Indonesia.

RECENT FINDINGS

A total of eleven articles reporting DRMs in HIV-1 subjects from various regions between 2015-2020 in Indonesia are included. The prevalence of major DRMs on the RT gene in studies included varies from 3.4% to 34%. The CRF01_AE subtype stands out as the predominant variant. Notably, the prevalence of major DRMs in ART-experienced individuals is 22.1%, while ART-naïve individuals show a lower rate of 4.4%. Among the RT gene mutations, M184I/V emerges as the most prevalent (10.5%) within the nucleos(t)ide reverse transcriptase inhibitors (NRTI) group, while K103N leads among the non-NRTI (NNRTI) group, with a frequency of 6.4%. Regionally, North Sulawesi records the highest prevalence of major DRMs in the RT gene at 21.1%, whereas Riau and Central Papua exhibit the lowest rates at 3.4%. Significant variations in drug resistance mutations within the RT gene across Indonesian regions highlight the importance of closely monitoring and evaluating the effectiveness of current antiretroviral therapy (ART) regimens. Considerably, more studies are needed to understand better and overcome the emergence of DRMs on HIV-1 patients in Indonesia.

Integrase inhibitors: current protagonists in antiretroviral therapy

Since HIV was identified as the etiological agent of AIDS, there have been significant advances in antiretroviral therapy (ART) that has reduced morbidity/mortality. Still, the viral genome's high mutation rate, suboptimal ART regimens, incomplete adherence to therapy and poor control of the viral load generate variants resistant to multiple drugs. Licensing over 30 anti-HIV drugs worldwide, including integrase inhibitors, has marked a milestone since they are potent and well-tolerated drugs. In addition, they favor a faster recovery of CD4+ T cells. They also increase the diversity profile of the gut microbiota and reduce inflammatory markers. All of these highlight the importance of including them in different ART regimens.

Long-term outcomes of highly experienced people with HIV undergoing salvage therapy with raltegravir

Raltegravir and other third-line drugs have shown promise in improving outcomes in treatment-experienced patients. However, the efficacy and tolerability of these agents vary. This study assessed real-life virologic success, long-term survival, and adverse events in patients receiving raltegravir or other third-line drugs as salvage regimens. This retrospective cohort study included adults who experienced treatment failure (human immunodeficiency syndrome-1 RNA plasma viral load >1000 copies/mL) and subsequently initiated raltegravir or other third-line drugs (darunavir/ritonavir, maraviroc, or etravirine). Propensity score matching methods were employed to account for differences at the time of switching from failing antiretroviral therapy regimens. The matched subset was analyzed using the Kaplan-Meier method and Generalized Wilcoxon tests to evaluate the probability of achieving virologic suppression (plasma viral load <50 copies/mL). Mortality rates, toxicity, treatment interruption, virologic failure, and loss to follow-up were determined using Poisson regression. One hundred and sixty-eight patients initiating salvage regimens were included, with 123 receiving raltegravir and 45 other third-line drugs. Propensity score matching resulted in a subset of 90 patients, 45 in each group. During the follow-up period, there were no significant differences observed between the groups in terms of virologic suppression (77.8% vs 82.2%, P = .73), mortality rates (4.04 vs 6.18 persons per 100 person-years [p-y]; P = .67), drug toxicity (0.00 vs 2.06 persons per 100 p-y; P = .49), treatment interruption (8.07 vs 0.00 persons per 100 p-y; P = .06), virologic failure (2.02 vs 4.12 persons per 100 p-y; P = .61), and loss of follow-up (6.05 vs 4.12 persons per 100 p-y; P = .70). Our findings indicate comparable survival and virological success rates between raltegravir and other drugs used in salvage regimens. Similar rates of drug toxicity, treatment interruption, virologic failure, and loss of follow-up were also observed. These results suggest that raltegravir may be a viable option for salvage therapy, demonstrating outcomes comparable to other third-line drugs in real life.

Field performance and cost-effectiveness of a point-of-care triage test for HIV virological failure in Southern Africa

INTRODUCTION

Antiretroviral therapy (ART) monitoring using viral load (VL) testing is challenging in high-burden, limited-resources settings. Chemokine IP-10 (interferon gamma-induced protein 10) strongly correlates with human immunodeficiency virus (HIV) VL. Its determination could serve to predict virological failure (VF) and to triage patients requiring VL testing. We assessed the field performance of a semi-quantitative IP-10 lateral flow assay (LFA) for VF screening in South Africa, and the cost-effectiveness of its implementation in Mozambique.

METHODS

A cross-sectional study was conducted between June and December 2021 in three primary health clinics in the Western Cape. Finger prick capillary blood was collected from adults on ART for ≥1 year for direct application onto the IP-10 LFA (index test) and compared with a plasma VL result ≤1 month prior (reference test). We estimated the area under the receiver operating characteristic curves (AUC), sensitivity and specificity, to evaluate IP-10 LFA prediction of VF (VL>1000 copies/ml). A decision tree model was used to investigate the cost-effectiveness of integrating IP-10 LFA combined with VL testing into the current Mozambican ART monitoring strategy. Averted disability-adjusted life years (DALYs) and HIV acquisitions, and incremental cost-effectiveness ratios were estimated.

RESULTS

Among 209 participants (median age 38 years and 84% female), 18% had VF. Median IP-10 LFA values were higher among individuals with VF compared to those without (24.0 vs. 14.6; p<0.001). The IP-10 LFA predicted VF with an AUC = 0.76 (95% confidence interval (CI) 0.67-0.85), 91.9% sensitivity (95% CI 78.1-98.3) and 35.1% specificity (95% CI 28.0-42.7). Integrating the IP-10 LFA in a setting with 20% VF prevalence and 61% VL testing coverage could save 13.0% of costs and avert 14.9% of DALYs and 55.7% new HIV acquisitions. Furthermore, its introduction was estimated to reduce the total number of routine VL tests required for ART monitoring by up to 68%.

CONCLUSIONS

The IP-10 LFA is an effective VF triage test for routine ART monitoring. Combining a highly sensitive, low-cost IP-10 LFA-based screening with targeted VL confirmatory testing could result in significant healthcare quality improvements and cost savings in settings with limited access to VL testing.

Diagnostic accuracy of a point-of-care urine tenofovir assay, and associations with HIV viraemia and drug resistance among people receiving dolutegravir and efavirenz-based antiretroviral therapy

INTRODUCTION

Novel point-of-care assays which measure urine tenofovir (TFV) concentrations may have a role in improving adherence monitoring for people living with HIV (PLHIV) receiving antiretroviral therapy (ART). However, further studies of their diagnostic accuracy, and whether results are associated with viraemia and drug resistance, are needed to guide their use, particularly in the context of the global dolutegravir rollout.

METHODS

We conducted a cross-sectional evaluation among PLHIV receiving first-line ART containing tenofovir disoproxil fumarate at enrolment into a randomized trial in two South African public sector clinics. We calculated the diagnostic accuracy of the Abbott point-of-care immunoassay to detect urine TFV compared to liquid chromatography-tandem mass spectrometry (LC-MS/MS). We evaluated the association between point-of-care urine TFV results and self-reported adherence, viraemia ≥1000 copies/ml and HIV drug resistance, among people receiving either efavirenz or dolutegravir-based ART.

RESULTS

Between August 2020 and March 2022, we enrolled 124 participants. The median age was 39 (IQR 34-45) years, 55% were women, 74 (59.7%) were receiving efavirenz and 50 (40.3%) dolutegravir. The sensitivity and specificity of the immunoassay to detect urine TFV ≥1500 ng/ml compared to LC-MS/MS were 96.1% (95% CI 90.0-98.8) and 95.2% (75.3-100.0), respectively. Urine TFV results were associated with short (p<0.001) and medium-term (p = 0.036) self-reported adherence. Overall, 44/124 (35.5%) had viraemia, which was associated with undetectable TFV in those receiving efavirenz (OR 6.01, 1.27-39.0, p = 0.014) and dolutegravir (OR 25.7, 4.20-294.8, p<0.001). However, in those with viraemia while receiving efavirenz, 8/27 (29.6%) had undetectable urine TFV, compared to 11/17 (64.7%) of those receiving dolutegravir. Drug resistance was detected in 23/27 (85.2%) of those receiving efavirenz and only 1/16 (6.3%) of those receiving dolutegravir. There was no association between urine TFV results and drug resistance.

CONCLUSIONS

Among PLHIV receiving ART, a rapid urine TFV immunoassay can be used to accurately monitor urine TFV levels compared to the gold standard of LC-MS/MS. Undetectable point-of-care urine TFV results were associated with viraemia, particularly among people receiving dolutegravir.

TRIAL REGISTRATION

Pan-African Clinical Trials Registry: PACTR202001785886049.

The Integrase: An Overview of a Key Player Enzyme in the Antiviral Scenario

Integration of a desossiribonucleic acid (DNA) copy of the viral ribonucleic acid (RNA) into host genomes is a fundamental step in the replication cycle of all retroviruses. The highly conserved virus-encoded Integrase enzyme (IN; EC 2.7.7.49) catalyzes such a process by means of two consecutive reactions named 3'-processing (3-P) and strand transfer (ST). The Authors report and discuss the major discoveries and advances which mainly contributed to the development of Human Immunodeficiency Virus (HIV) -IN targeted inhibitors for therapeutic applications. All the knowledge accumulated over the years continues to serve as a valuable resource for the design and development of effective antiretroviral drugs.

Genetic characterization of HIV-1 viruses among cases with antiretroviral therapy failure in Suzhou City, China

BACKGROUND

This retrospective study aimed to characterize the distribution of HIV-1 genotypes and the prevalence of drug resistance mutations in people with antiretroviral treatment (ART) failure in Suzhou City, China.

METHODS

Pol gene of HIV-1 viruses in blood samples of EDTA anticoagulants from 398 patients with failed antiviral treatment was successfully amplified by using an in-house assay. Drug resistance mutations were analyzed by using the Stanford HIV Drug Resistance Database system ( https://hivdb.stanford.edu/hivdb/by-mutations/ ). HIV-1 genotypes were determined by the REGA HIV subtyping tool (version 3.46, https://www.genomedetective.com/app/typingtool/hiv ). Near full-length genomes (NFLG) of HIV-1 viruses were obtained by next generation sequencing method.

RESULTS

Sequences analysis of the pol gene revealed that CRF 01_AE (57.29%, 228/398) was the dominant subtype circulating in Suzhou City, followed by CRF 07_BC (17.34%, 69/398), subtype B (7.54%, 30/398), CRF 08_BC (6.53%, 26/398), CRF 67_01B (3.02%, 12/398) and CRF55_01B (2.51%, 10/398). The overall prevalence of drug-resistant mutations in cases with ART failure was 64.57% (257/398), including 45.48% (181/398) for nucleotide reverse transcriptase inhibitors (NRTIs) mutations, 63.32% (252/398) for non-nucleoside reverse transcriptase inhibitors (NNRTIs) mutations, and 3.02% (12/398) for protease inhibitors (PIs) mutations. Ten near full-length genomes (NFLG) of HIV-1 viruses were identified, including six recombinants of CRF 01_AE and subtype B, two recombinants of CRF 01_AE, subtype B and subtype C sequences, one recombinant of CRF 01_AE and subtype C and one recombinant of CRF 01_AE, subtype A1 and subtype C.

CONCLUSIONS

The high prevalence of drug-resistant HIV-1 viruses was a serious challenge for HIV prevention and treatment of people with HIV infection. Treatment regimens for ART failure patients should be adjusted over time based on the outcome of drug resistance tests. NFLG sequencing facilitates the identification of new recombinants of HIV-1.

AI-Aided Search for New HIV-1 Protease Ligands

The availability of drugs capable of blocking the replication of microorganisms has been one of the greatest triumphs in the history of medicine, but the emergence of an ever-increasing number of resistant strains poses a serious problem for the treatment of infectious diseases. The search for new potential ligands for proteins involved in the life cycle of pathogens is, therefore, an extremely important research field today. In this work, we have considered the HIV-1 protease, one of the main targets for AIDS therapy. Several drugs are used today in clinical practice whose mechanism of action is based on the inhibition of this enzyme, but after years of use, even these molecules are beginning to be interested by resistance phenomena. We used a simple artificial intelligence system for the initial screening of a data set of potential ligands. These results were validated by docking and molecular dynamics, leading to the identification of a potential new ligand of the enzyme which does not belong to any known class of HIV-1 protease inhibitors. The computational protocol used in this work is simple and does not require large computational power. Furthermore, the availability of a large number of structural information on viral proteins and the presence of numerous experimental data on their ligands, with which it is possible to compare the results obtained with computational methods, make this research field the ideal terrain for the application of these new computational techniques.

HIV virologic response, patterns of drug resistance mutations and correlates among adolescents and young adults: A cross-sectional study in Tanzania

BACKGROUND

The emergence of HIV drug resistance mutations (DRMs) is of significant threat to achieving viral suppression (VS) in the quest to achieve global elimination targets. We hereby report virologic outcomes and patterns of acquired DRMs and its associated factors among adolescents and young adults (AYA) from a broader HIV drug resistance surveillance conducted in Tanzania.

METHODS

Data of AYA was extracted from a cross-sectional study conducted in 36 selected facilities using a two-stage cluster sampling design. Dried blood spot (DBS) samples were collected and samples with a viral load (VL) ≥1000 copies/mL underwent genotyping for the HIV-1 pol gene. Stanford HIV database algorithm predicted acquired DRMs, Fisher's exact test and multivariable logistic regression assessed factors associated with DRMs and VS, respectively.

FINDINGS

We analyzed data of 578 AYA on antiretroviral therapy (ART) for 9-15 and ≥ 36 months; among them, 91.5% and 88.2% had VS (VL<1000copies/mL) at early and late time points, respectively. Genotyping of 64 participants (11.2%) who had VL ≥1000 copies/ml detected 71.9% of any DRM. Clinically relevant DRMs were K103N, M184V, M41L, T215Y/F, L210W/L, K70R, D67N, L89V/T, G118R, E138K, T66A, T97A and unexpectedly absent K65R. Participants on a protease inhibitor (PI) based regimen were twice as likely to not achieve VS compared to those on integrase strand transfer inhibitors (INSTI). The initial VL done 6 months after ART initiation of ≥1000copies/mL was the primary factor associated with detecting DRMs (p = .019).

CONCLUSIONS

VS amongst AYA is lower than the third UNAIDs target. Additionally, a high prevalence of ADR and high levels of circulating clinically relevant DRMs may compromise the long-term VS in AYA. Furthermore, the first VL result of ≥1000copies/ml after ART initiation is a significant risk factor for developing DRMs. Thus, strict VL monitoring for early identification of treatment failure and genotypic testing during any ART switch is recommended to improve treatment outcomes for AYA.

Immunological, Cognitive, and Psychiatric Outcomes After Initiating Efavirenz- and Dolutegravir-based Antiretroviral Therapy During Acute Human Immunodeficiency Virus Infection

BACKGROUND

Efavirenz (EFV)- and dolutegravir (DTG)-based antiretroviral therapy (ART) is the former and current recommended regimen for treatment-naive individuals with human immunodeficiency virus type 1 (HIV-1). Whether they impact the immunological and neuropsychiatric profile differentially remains unclear.

METHODS

This retrospective analysis included 258 participants enrolled during acute HIV-1 infection (AHI). Participants initiated 1 of 3 ART regimens during AHI: EFV-based (n = 131), DTG-based (n = 92), or DTG intensified with maraviroc (DTG/MVC, n = 35). All regimens included 2 nucleoside reverse-transcriptase inhibitors and were maintained for 96 weeks. CD4+ and CD8+ T-cell counts, mood symptoms, and composite score on a 4-test neuropsychological battery (NPZ-4) were compared.

RESULTS

At baseline, the median age was 26 years, 99% were male, and 36% were enrolled during Fiebig stage I-II. Plasma viral suppression at weeks 24 and 96 was similar between the groups. Compared with the EFV group, the DTG group showed greater increments of CD4+ (P < .001) and CD8+ (P = .015) T-cell counts but a similar increment of CD4/CD8 ratio at week 96. NPZ-4 improvement was similar between the 2 groups at week 24 but greater in the DTG group at week 96 (P = .005). Depressive mood and distress symptoms based on the Patient Health Questionnaire and distress thermometer were similar between the 2 groups at follow-up. Findings for the DTG/MVC group were comparable to those for the DTG group vs the EFV group.

CONCLUSIONS

Among individuals with AHI, 96 weeks of DTG-based ART was associated with greater increments of CD4+ and CD8+ T-cell counts and improvement in cognitive performance.

Prevalence of HIV Transmitted Drug Resistance in Nanjing from 2018 to 2021

Background

Transmitted drug resistance (TDR) is a major challenge in the clinical management of acquired immunodeficiency syndrome (AIDS). Therefore, this study aimed to investigate the epidemic characteristics of and risk factors for human immunodeficiency virus (HIV)-1 TDR in Nanjing from 2018 to 2021 to provide support for clinical management.

Methods

The HIV-1 Pol gene was amplified by nested reverse transcription polymerase chain reaction from venous blood of 1190 HIV-infected patients who did not receive antiviral therapy, and the amplified product was sequenced using an in-house sequencing method. The sequencing result was compared with the HIV drug resistance database from Stanford University to elucidate the rates of antiviral drug resistance and distribution of drug-resistant mutation sites. Factors associated with TDR were evaluated using a logistic regression model.

Results

Detection of drug resistance at the gene level was successful in 1138 of 1190 HIV-1-infected patients (95.6%), and the overall 4-year drug resistance rate was 8.2% (93/1138). The drug resistance rate was higher for non-nucleoside reverse transcriptase inhibitors (NNRTIs; 6.7%) than for nucleoside reverse transcriptase inhibitors (NRTIs; 2.5%) or protease inhibitors (PIs; 0.1%) (χ ² = 83.907, P<0.0001). The most common NNRTI-related mutation was V179D/E followed by K103N. M184V was the dominant NRTI-associated mutation, and M46L/I was the most prevalent PI-associated mutation. A CD4⁺ T cell count of <50 cells/μL was significantly associated with an increased risk of TDR (OR=3.62, 95% CI: 1.38-9.51, P=0.009).

Conclusion

The prevalence of TDR in the city of Nanjing from 2018 to 2021 was at a moderate epidemic risk according to World Health Organization standards. Continuous monitoring of TDR can inform clinical diagnosis and treatment. Patients with advanced disease and a low CD4⁺ T lymphocyte count are more likely to have TDR in Nanjing.

Prevalence of Transmitted Drug Resistance among HIV-1 Patients in the Aegean Region: Results from the Western Part of Turkey

OBJECTIVES

This study aimed to analyze the antiretroviral drug resistance in antiretroviral treatment-naïve HIV-positive patients in the Aegean Region of Turkey from 2012 to 2019.

METHODS

The study included 814 plasma samples from treatment-naïve HIV-positive patients. Drug resistance analysis was performed by Sanger sequencing (SS) between 2012-2017 and by next-generation sequencing sequencing (NGS) between 2018-2019. SS was used to analyze resistance mutations in the protease (PR) and reverse transcriptase (RT) gene regions using a ViroSeq HIV-1 Genotyping System. PCR products were analyzed with an ABI3500 GeneticAnalyzer (Applied Biosystems). The sequencing of the HIV genome in the PR, RT, and integrase gene regions was carried out using MiSeq NGS technology. Drug resistance mutations and subtypes were interpreted using the Stanford University HIV-1 drug resistance database.

RESULTS

Transmitted drug resistance (TDR) mutation was detected in 34/814 (4.1 %) samples. Nonnucleoside reverse transcriptase inhibitor (NNRTI), nucleoside reverse transcriptase inhibitor (NRTI), and protease inhibitor (PI) mutations were identified in 1.4 % (n =12), 2.4 % (n =20), and 0.3 % (n = 3) of samples, respectively. The most common subtypes were B (53.1 %), A (10.9%), CRF29_BF (10.6%), and B + CRF02_AG (8,2%). The most common TDR mutations were E138A (3.4%), T215 revertants (1.7%), M41L (1.5%), and K103N (1.1%).

CONCLUSION

Transmitted drug resistance rate in the Aegean Region is compatible with national and regional data. Routine surveillance of resistance mutations may guide the safe and correct selection of initial drug combinations for antiretroviral therapy. The identification of HIV-1 subtypes and recombinant forms in Turkey may contribute to international molecular epidemiological data.

HIV-1 Protease as DNA Immunogen against Drug Resistance in HIV-1 Infection: DNA Immunization with Drug Resistant HIV-1 Protease Protects Mice from Challenge with Protease-Expressing Cells

DNA immunization with HIV-1 protease (PR) is advanced for immunotherapy of HIV-1 infection to reduce the number of infected cells producing drug-resistant virus. A consensus PR of the HIV-1 FSU_A strain was designed, expression-optimized, inactivated (D25N), and supplemented with drug resistance (DR) mutations M46I, I54V, and V82A common for FSU_A. PR variants with D25N/M46I/I54V (PR_Ai2mut) and with D25N/M46I/I54V/V82A (PR_Ai3mut) were cloned into the DNA vaccine vector pVAX1, and PR_Ai3mut, into a lentiviral vector for the transduction of murine mammary adenocarcinoma cells expressing luciferase 4T1luc2. BALB/c mice were DNA-immunized by intradermal injections of PR_Ai, PR_Ai2mut, PR_Ai3mut, vector pVAX1, or PBS with electroporation. All PR variants induced specific CD8+ T-cell responses revealed after splenocyte stimulation with PR-derived peptides. Splenocytes of mice DNA-immunized with PR_Ai and PR_Ai2mut were not activated by peptides carrying V82A, whereas splenocytes of PR_Ai3mut-immunized mice recognized both peptides with and without V82A mutation. Mutations M46I and I54V were immunologically silent. In the challenge study, DNA immunization with PR_Ai3mut protected mice from the outgrowth of subcutaneously implanted adenocarcinoma 4T1luc2 cells expressing PR_Ai3mut; a tumor was formed only in 1/10 implantation sites and no metastases were detected. Immunizations with other PR variants were not protective; all mice formed tumors and multiple metastasis in the lungs, liver, and spleen. CD8+ cells of PR_Ai3mut DNA-immunized mice exhibited strong IFN-γ/IL-2 responses against PR peptides, while the splenocytes of mice in other groups were nonresponsive. Thus, immunization with a DNA plasmid encoding inactive HIV-1 protease with DR mutations suppressed the growth and metastatic activity of tumor cells expressing PR identical to the one encoded by the immunogen. This demonstrates the capacity of T-cell response induced by DNA immunization to recognize single DR mutations, and supports the concept of the development of immunotherapies against drug resistance in HIV-1 infection. It also suggests that HIV-1-infected patients developing drug resistance may have a reduced natural immune response against DR HIV-1 mutations causing an immune escape.

Defensins: defenders of human reproductive health

BACKGROUND

Reproductive tract infection is an important factor leading to male and female infertility. Among female infertility factors, microbial and viral infections are the main factors affecting female reproductive health and causing tubal infertility, ectopic tubal pregnancy and premature delivery. Among male infertility factors, 13-15% of male infertility is related to infection. Defensins are cationic antibacterial and antiviral peptides, classified into α-defensins, β-defensins and θ-defensins. Humans only have α-defensins and β-defensins. Apart from their direct antimicrobial functions, defensins have an immunomodulatory function and are involved in many physiological processes. Studies have shown that defensins are widely distributed in the female reproductive tract (FRT) and male reproductive tract (MRT), playing a dual role of host defence and fertility protection. However, to our knowledge, the distribution, regulation and function of defensins in the reproductive tract and their relation to reproduction have not been reviewed.

OBJECTIVE AND RATIONALE

This review summarizes the expression, distribution and regulation of defensins in the reproductive tracts to reveal the updated research on the dual role of defensins in host defence and the protection of fertility.

SEARCH METHODS

A systematic search was conducted in PubMed using the related keywords through April 2022. Related data from original researches and reviews were integrated to comprehensively review the current findings and understanding of defensins in the human reproductive system. Meanwhile, female and male transcriptome data in the GEO database were screened to analyze defensins in the human reproductive tracts.

OUTCOMES

Two transcriptome databases from the GEO database (GSE7307 and GSE150852) combined with existing researches reveal the expression levels and role of the defensins in the reproductive tracts. In the FRT, a high expression level of α-defensin is found, and the expression levels of defensins in the vulva and vagina are higher than those in other organs. The expression of defensins in the endometrium varies with menstrual cycle stages and with microbial invasion. Defensins also participate in the local immune response to regulate the risk of spontaneous preterm birth. In the MRT, a high expression level of β-defensins is also found. It is mainly highly expressed in the epididymal caput and corpus, indicating that defensins play an important role in sperm maturation. The expression of defensins in the MRT varies with androgen levels, age and the status of microbial invasion. They protect the male reproductive system from bacterial infections by neutralizing lipopolysaccharide and downregulating pro-inflammatory cytokines. In addition, animal and clinical studies have shown that defensins play an important role in sperm maturation, motility and fertilization.

WIDER IMPLICATIONS

As a broad-spectrum antimicrobial peptide without drug resistance, defensin has great potential for developing new natural antimicrobial treatments for reproductive tract infections. However, increasing evidence has shown that defensins can not only inhibit microbial invasion but can also promote the invasion and adhesion of some microorganisms in certain biological environments, such as human immunodeficiency virus. Therefore, the safety of defensins as reproductive tract anti-infective drugs needs more in-depth research. In addition, the modulatory role of defensins in fertility requires more in-depth research since the current conclusions are based on small-size samples. At present, scientists have made many attempts at the clinical transformation of defensins. However, defensins have problems such as poor stability, low bioavailability and difficulties in their synthesis. Therefore, the production of safe, effective and low-cost drugs remains a challenge.

HIV drug resistance in a community-randomized trial of universal testing and treatment: HPTN 071 (PopART)

INTRODUCTION

Universal HIV testing and treatment (UTT) has individual and public health benefits. HPTN 071 (PopART), a community-randomized trial in Zambia and South Africa, demonstrated that UTT decreased HIV incidence. This endpoint was assessed in a cohort of >48,000 randomly selected adults in the study communities. We evaluated the impact of UTT on HIV drug resistance in this cohort and compared other resistance-related outcomes in participants with recent versus non-recent HIV infection.

METHODS

Two years after the start of HPTN 071 (2016-2017), 6259 participants were HIV positive and 1902 were viremic (viral load >400 copies/ml). HIV genotyping and antiretroviral (ARV) drug testing were performed for viremic participants in three groups: seroconverters (infected <1 year), non-seroconverters (infected >1 year, random subset) and participants with unknown duration of infection (random subset). A two-stage cluster-based approach was used to assess the impact of the study intervention on drug resistance. Treatment failure was defined as being viremic with ARV drugs detected. Participants were classified as ARV naïve based on self-report and ARV drug testing.

RESULTS

Genotyping results were obtained for 758 participants (143 seroconverters; 534 non-seroconverters; and 81 unknown duration of infection). The estimated prevalence of resistance in the study communities was 37% for all viremic persons and 11% for all HIV-positive persons. There was no association between UTT and drug resistance. Resistance was detected in 14.0% of seroconverters and 40.8% of non-seroconverters (non-nucleoside reverse transcriptase inhibitor resistance: 14.0% and 39.9%; nucleoside/nucleotide reverse transcriptase inhibitor resistance: 0.7% and 15.5%; protease inhibitor resistance: 0% and 1.9%; multi-class resistance: 0.7% and 16.1%, respectively). ARV drugs were detected in 2/139 (1.4%) of seroconverters and 94/534 (17.6%) of non-seroconverters tested. These participants were classified as failing ART; 88 (93.6%) of the non-seroconverters failing ART had resistance. Mutations used for surveillance of transmitted drug resistance were detected in 10.5% of seroconverters and 15.1% of non-seroconverters who were ARV naive.

CONCLUSIONS

UTT was not associated with an increase in drug resistance in this cohort. Higher rates of drug resistance and multi-class resistance were observed in non-seroconverters compared to seroconverters.

Highly dampened HIV-specific cytolytic effector T cell responses define viremic non-progression

This study reports on HIV-specific T cell responses in HIV-1 infected Viremic Non-Progressors (VNPs), a rare group of people living with HIV that exhibit asymptomatic infection over several years accompanied by stable CD4+ T cell counts in spite of ongoing viral replication. We attempted to identify key virus-specific functional attributes that could underlie the apparently paradoxical virus-host equilibrium observed in VNPs. Our results revealed modulation of HIV-specific CD4+ and CD8+ effector T cell responses in VNPs towards a dominant non-cytolytic profile with concomitantly diminished degranulation (CD107a+) ability. Further, the HIV specific CD8+ effector T cell response was primarily enriched for MIP-1β producing cells. As expected, concordant with better viral suppression, VCs exhibit a robust cytolytic T cell response. Interestingly, PuPs shared features common to both these responses but did not exhibit a CD4+ central memory IFN-γ producing Gag-specific response that was shared by both non-progressor (VC and VNP) groups, suggesting CD4 helper response is critical for non-progression. Our study also revealed that cytolytic response in VNPs is primarily limited to polyfunctional cells while both monofunctional and polyfunctional cells significantly contribute to cytolytic responses in VCs. To further understand mechanisms underlying the unique HIV-specific effector T cell response described here in VNPs we also evaluated and demonstrated a possible role for altered gut homing in these individuals. Our findings inform immunotherapeutic interventions to achieve functional cures in the context of ART resistance and serious non AIDS events.

Therapeutic potentials of CRISPR-Cas genome editing technology in human viral infections

Viral infections are a common cause of morbidity worldwide. The emergence of Coronavirus Disease 2019 (COVID-19) has led to more attention to viral infections and finding novel therapeutics. The CRISPR-Cas9 system has been recently proposed as a potential therapeutic tool for the treatment of viral diseases. Here, we review the research progress in the use of CRISPR-Cas technology for treating viral infections, as well as the strategies for improving the delivery of this gene-editing tool in vivo. Key challenges that hinder the widespread clinical application of CRISPR-Cas9 technology are also discussed, and several possible directions for future research are proposed.

Exploring the mechanisms behind HIV drug resistance in sub-Saharan Africa: conceptual mapping of a complex adaptive system based on multi-disciplinary expert insights

BACKGROUND

HIV drug resistance (HIVDR) continues to threaten the effectiveness of worldwide antiretroviral therapy (ART). Emergence and transmission of HIVDR are driven by several interconnected factors. Though much has been done to uncover factors influencing HIVDR, overall interconnectedness between these factors remains unclear and African policy makers encounter difficulties setting priorities combating HIVDR. By viewing HIVDR as a complex adaptive system, through the eyes of multi-disciplinary HIVDR experts, we aimed to make a first attempt to linking different influencing factors and gaining a deeper understanding of the complexity of the system.

METHODS

We designed a detailed systems map of factors influencing HIVDR based on semi-structured interviews with 15 international HIVDR experts from or with experience in sub-Saharan Africa, from different disciplinary backgrounds and affiliated with different types of institutions. The resulting detailed system map was conceptualized into three main HIVDR feedback loops and further strengthened with literature evidence.

RESULTS

Factors influencing HIVDR in sub-Saharan Africa and their interactions were sorted in five categories: biology, individual, social context, healthcare system and 'overarching'. We identified three causal loops cross-cutting these layers, which relate to three interconnected subsystems of mechanisms influencing HIVDR. The 'adherence motivation' subsystem concerns the interplay of factors influencing people living with HIV to alternate between adherence and non-adherence. The 'healthcare burden' subsystem is a reinforcing loop leading to an increase in HIVDR at local population level. The 'ART overreliance' subsystem is a balancing feedback loop leading to complacency among program managers when there is overreliance on ART with a perceived low risk to drug resistance. The three subsystems are interconnected at different levels.

CONCLUSIONS

Interconnectedness of the three subsystems underlines the need to act on the entire system of factors surrounding HIVDR in sub-Saharan Africa in order to target interventions and to prevent unwanted effects on other parts of the system. The three theories that emerged while studying HIVDR as a complex adaptive system form a starting point for further qualitative and quantitative investigation.

Infectious RNA: Human Immunodeficiency Virus (HIV) Biology, Therapeutic Intervention, and the Quest for a Vaccine

Different mechanisms mediate the toxicity of RNA. Genomic retroviral mRNA hijacks infected host cell factors to enable virus replication. The viral genomic RNA of the human immunodeficiency virus (HIV) encompasses nine genes encoding in less than 10 kb all proteins needed for replication in susceptible host cells. To do so, the genomic RNA undergoes complex alternative splicing to facilitate the synthesis of the structural, accessory, and regulatory proteins. However, HIV strongly relies on the host cell machinery recruiting cellular factors to complete its replication cycle. Antiretroviral therapy (ART) targets different steps in the cycle, preventing disease progression to the acquired immunodeficiency syndrome (AIDS). The comprehension of the host immune system interaction with the virus has fostered the development of a variety of vaccine platforms. Despite encouraging provisional results in vaccine trials, no effective vaccine has been developed, yet. However, novel promising vaccine platforms are currently under investigation.

Antiretroviral Imprints and Genomic Plasticity of HIV-1 pol in Non-clade B: Implications for Treatment

Combinational antiretroviral therapy (cART) is the most effective tool to prevent and control HIV-1 infection without an effective vaccine. However, HIV-1 drug resistance mutations (DRMs) and naturally occurring polymorphisms (NOPs) can abrogate cART efficacy. Here, we aimed to characterize the HIV-1 pol mutation landscape in Cameroon, where highly diverse HIV clades circulate, and identify novel treatment-associated mutations that can potentially affect cART efficacy. More than 8,000 functional Cameroonian HIV-1 pol sequences from 1987 to 2020 were studied for DRMs and NOPs. Site-specific amino acid frequencies and quaternary structural features were determined and compared between periods before (≤2003) and after (2004-2020) regional implementation of cART. cART usage in Cameroon induced deep mutation imprints in reverse transcriptase (RT) and to a lower extent in protease (PR) and integrase (IN), according to their relative usage. In the predominant circulating recombinant form (CRF) 02_AG (CRF02_AG), 27 canonical DRMs and 29 NOPs significantly increased or decreased in RT during cART scale-up, whereas in IN, no DRM and only seven NOPs significantly changed. The profound genomic imprints and higher prevalence of DRMs in RT compared to PR and IN mirror the dominant use of reverse transcriptase inhibitors (RTIs) in sub-Saharan Africa and the predominantly integrase strand transfer inhibitor (InSTI)-naïve study population. Our results support the potential of InSTIs for antiretroviral treatment in Cameroon; however, close surveillance of IN mutations will be required to identify emerging resistance patterns, as observed in RT and PR. Population-wide genomic analyses help reveal the presence of selective pressures and viral adaptation processes to guide strategies to bypass resistance and reinstate effective treatment.

A Meta-Analytic Review of the Effect of Antiretroviral Therapy on Neurocognitive Outcomes in Adults Living with HIV-1 in Low-and Middle-Income Countries

HIV-associated neurocognitive impairment remains a challenge even in the era of antiretroviral therapy (ART). Over 90% of people living with HIV are in low- and middle-income countries. Hence, it is not surprising that such countries bear a considerable burden of comorbidities like HIV-associated neurocognitive impairment despite an overall increase in life expectancy. The literature suggests differences in patient characteristics, clinical profile, prevalent HIV subtypes, treatment choices, pharmacogenetics, and socioeconomic factors between low- and middle-income countries compared with high-income countries. Therefore, we aimed to evaluate the effect of ART on neurocognitive outcomes in low- and middle-income countries. A comprehensive search of five databases (PubMed, CINAHL, CENTRAL, PsychInfo, Google scholar) for studies published between 1996 to 2020 was performed to identify studies that reported neurocognitive outcomes in ART-treated and ART naïve HIV positive individuals. Two independent reviewers conducted study screening, data extraction, and evaluation of the risk of bias. Pooled effect size estimates (Hedges' g) and 95% CI were computed using random-effects models. Sensitivity analysis, subgroup analysis, meta-regression, and evaluation of publication bias were also conducted. Forty studies (24 cross-sectional, 13 longitudinal studies, and two randomized controlled trials) contributed to a series of meta-analyses. We found significant small to moderate effects of antiretroviral therapy for global cognition (Hedges' g observed = 0.30; 95% CI: 0.15, 0.44; k = 25; p = 0.0003; I² = 92.1%; tau = 0.32; Q = 305.1), executive function (Hedges' g = 0.24, 95%CI: 0.02,0.46; p-0.04; k = 8; I² = 37.5%; tau = 0.23; Q = 11.2), and speed of information processing (Hedges' g = 0.25, 95% CI: 0.05, 0.45; k = 9; p = 0.02; I² = 86.4%; tau = 0.21; Q = 58.9). We found no significant ART effect on attention-working memory, learning and memory, motor function, and verbal fluency. No significant effect was seen with the duration of therapy, efavirenz use, and Central Penetrating Effectiveness (CPE) of antiretroviral therapy. Subgroup analyses identified study design (between-group and within-group; cross-sectional and longitudinal) and normative scores as significant sources of heterogeneity. Meta-regression analysis indicated that nadir CD4 modified the magnitude of ART's effect on cognitive outcomes. Age, gender, and country income-group were not significant moderators. Our findings provide systematic evidence that antiretroviral therapy improves neurocognitive outcomes in the domains of global cognition, executive function and speed of information processing, of people living with HIV in low- and middle-income countries, especially those with advanced immunosuppression. However, these findings are not definitive as they are limited by the probability of publication bias, high heterogeneity, and exclusion of significant confounders. Prospero registration number: CRD42020203791.

Low prevalence of doravirine-associated resistance mutations among polish human immunodeficiency-1 (HIV-1)–infected patients

Introduction

Doravirine (DOR) is a novel non-nucleoside reverse transcriptase inhibitor (NNRTI) that retains activity against common NNRTI resistance mutations. In this study, we aimed to investigate the prevalence of DOR resistance mutations compared with that of resistance mutations for other NNRTIs among HIV-1-infected treatment‐experienced and -naïve patients from Poland.

Methods

Resistance to DOR and other NNRTIs was assessed in two datasets: 1760 antiretroviral treatment-naïve HIV-1 patients and 200 treatment‐experienced patients. All 1960 sequences were derived from the patients using bulk sequencing. For resistance analyses, Stanford HIV drug resistance database scores were used.

Results

Overall, DOR resistance was present in 32 patients (1.62%), of whom 13 (0.74%) were naïve and 19 (9.50%) were treatment-experienced. The most common DOR resistance mutations observed among the naïve patients were A98G and K101E (0.2% each), and those among cART-experienced patients were L100I (2.0%), K101E, V108I, H221Y, and P225H (1.5% each). Furthermore, among the naïve patients, less common resistance to DOR (0.7%) compared with that to nevirapine (NVP) (2.1%; p = 0.0013) and rilpivirine (5.40%; p < 0.0001) was observed. For sequences obtained from treatment-experienced patients, the frequency of resistance to DOR (9.5%) was lower than that for efavirenz (25.5%; p < 0.0001) and NVP (26.0%; p < 0.0001).

Conclusions

The frequency of transmitted drug resistance to DOR is low, allowing for effective treatment of antiretroviral treatment-naïve patients and rapid treatment initiation. In cART-experienced patients, this agent remains an attractive NNRTI option with a higher genetic barrier to resistance.

Drivers of HIV-1 drug resistance to non-nucleoside reverse-transcriptase inhibitors (NNRTIs) in nine southern African countries: a modelling study

INTRODUCTION

The rise of HIV-1 drug resistance to non-nucleoside reverse-transcriptase inhibitors (NNRTI) threatens antiretroviral therapy's long-term success (ART). NNRTIs will remain an essential drug for the management of HIV-1 due to safety concerns associated with integrase inhibitors. We fitted a dynamic transmission model to historical data from 2000 to 2018 in nine countries of southern Africa to understand the mechanisms that have shaped the HIV-1 epidemic and the rise of pretreatment NNRTI resistance.

METHODS

We included data on HIV-1 prevalence, ART coverage, HIV-related mortality, and survey data on pretreatment NNRTI resistance from nine southern Africa countries from a systematic review, UNAIDS and World Bank. Using a Bayesian hierarchical framework, we developed a dynamic transmission model linking data on the HIV-1 epidemic to survey data on NNRTI drug resistance in each country. We estimated the proportion of resistance attributable to unregulated, off-programme use of ART. We examined each national ART programme's vulnerability to NNRTI resistance by defining a fragility index: the ratio of the rate of NNRTI resistance emergence during first-line ART over the rate of switching to second-line ART. We explored associations between fragility and characteristics of the health system of each country.

RESULTS

The model reliably described the dynamics of the HIV-1 epidemic and NNRTI resistance in each country. Predicted levels of resistance in 2018 ranged between 3.3% (95% credible interval 1.9-7.1) in Mozambique and 25.3% (17.9-33.8) in Eswatini. The proportion of pretreatment NNRTI resistance attributable to unregulated antiretroviral use ranged from 6% (2-14) in Eswatini to 64% (26-85) in Mozambique. The fragility index was low in Botswana (0.01; 0.0-0.11) but high in Namibia (0.48; 0.16-10.17), Eswatini (0.64; 0.23-11.8) and South Africa (1.21; 0.83-9.84). The combination of high fragility of ART programmes and high ART coverage levels was associated with a sharp increase in pretreatment NNRTI resistance.

CONCLUSIONS

This comparison of nine countries shows that pretreatment NNRTI resistance can be controlled despite high ART coverage levels. This was the case in Botswana, Mozambique, and Zambia, most likely because of better HIV care delivery, including rapid switching to second-line ART of patients failing first-line ART.

HIV virological non-suppression and its associated factors in children on antiretroviral therapy at a major treatment centre in Southern Ghana: a cross-sectional study

BACKGROUND

Children living with human immunodeficiency virus (HIV) infection require lifelong effective antiretroviral therapy (ART). The goal of ART in HIV-infected persons is sustained viral suppression. There is limited information on virological non-suppression or failure and its associated factors in children in resource limited countries, particularly Ghana.

METHODS

A cross-sectional study of 250 children aged 8 months to 15 years who had been on ART for at least 6 months attending the Paediatric HIV clinic at Korle Bu Teaching hospital in Ghana was performed. Socio-demographic, clinical, laboratory and ART Adherence related data were collected using questionnaires as well as medical records review. Blood samples were obtained for viral load and CD4⁺ count determination. Viral load levels > 1000 copies/ml on ART was considered virological non-suppression. Logistic regression was used to identify factors associated with virological non-suppression.

RESULTS

The mean (±SD) age of the study participants was 11.4 ± 2.4 years and the proportion of males was 53.2%. Of the 250 study participants, 96 (38.4%) had virological non-suppression. After adjustment for significant variables, the factors associated with non-suppressed viral load were female gender (AOR 2.51 [95% CI 1.04-6.07], p = 0.041), having a previous history of treatment of tuberculosis (AOR 4.95 [95% CI 1.58-15.5], p = 0.006), severe CD4 immune suppression status at study recruitment (AOR 24.93 [95% CI 4.92-126.31], p < 0.001) and being on a nevirapine (NVP) based regimen (AOR 7.93 [95% CI 1.58-1.15], p = 0.005).

CONCLUSION

The prevelance of virological non-suppression was high. Virological non-suppression was associated with a previous history of TB treatment, female gender, severe CD4 immune suppression status at study recruitment and being on a NVP based regimen. Early initiation of ART and phasing out NVP-based regimen might improve viral load suppression in children. In addition, children with a history of TB may need focused measures to maximize virological suppression.

Second-generation mother-to-child HIV transmission in South Africa is characterized by poor outcomes

OBJECTIVE

The worldwide incidence of pregnancy for women living with perinatal HIV infection is increasing. Subsequently, there is growing risk of second-generation mother-to-child HIV transmission. The infant clinical outcomes for such a phenomenon have yet to be described.

DESIGN

As part of a wider observational study in KwaZulu-Natal, South Africa, six infants with in-utero HIV infection were identified as being born to mothers with perinatal HIV infection.

METHODS

Blood results and clinical data were collected in the first 3 years of life. In two cases, sample availability allowed confirmation by phylogenetic analysis of grandmother-to-mother-to-child HIV transmission.

RESULTS

Outcomes were poor in all six cases. All six mothers had difficulty administering twice daily combination antiretroviral therapy to their infants due to difficulties with acceptance, disclosure, poor health and being themselves long-term nonprogressors. Nonnucleoside reverse transcriptase inhibitor-resistant virus was detected in all mothers tested. None of the infants maintained suppression of viraemia on combination antiretroviral therapy. One infant died, and another was lost to follow-up.

CONCLUSION

As the numbers of second-generation mother-to-child transmissions increase, it is important to highlight that this mother-infant dyad represents an extremely vulnerable group. In order for them to survive and thrive, these infants' mothers require their specific needs to be addressed and given intensive support.

Diverse Human Immunodeficiency Virus-1 Drug Resistance Profiles at Screening for ACTG A5288: A Study of People Experiencing Virologic Failure on Second-line Antiretroviral Therapy in Resource-limited Settings

BACKGROUND

Human immunodeficiency virus (HIV) drug resistance profiles are needed to optimize individual patient management and to develop treatment guidelines. Resistance profiles are not well defined among individuals on failing second-line antiretroviral therapy (ART) in low- and middle-income countries (LMIC).

METHODS

Resistance genotypes were performed during screening for enrollment into a trial of third-line ART (AIDS Clinical Trials Group protocol 5288). Prior exposure to both nucleoside reverse transcriptase inhibitors (NRTIs) and non-NRTIs and confirmed virologic failure on a protease inhibitor-containing regimen were required. Associations of drug resistance with sex, age, treatment history, plasma HIV RNA, nadir CD4+T-cell count, HIV subtype, and country were investigated.

RESULTS

Plasma HIV genotypes were analyzed for 653 screened candidates; most had resistance (508 of 653; 78%) to 1 or more drugs. Genotypes from 133 (20%) showed resistance to at least 1 drug in a drug class, from 206 (32%) showed resistance to at least 1 drug in 2 drug classes, and from 169 (26%) showed resistance to at least 1 drug in all 3 commonly available drug classes. Susceptibility to at least 1 second-line regimen was preserved in 59%, as were susceptibility to etravirine (78%) and darunavir/ritonavir (97%). Susceptibility to a second-line regimen was significantly higher among women, younger individuals, those with higher nadir CD4+ T-cell counts, and those who had received lopinavir/ritonavir, but was lower among prior nevirapine recipients.

CONCLUSIONS

Highly divergent HIV drug resistance profiles were observed among candidates screened for third-line ART in LMIC, ranging from no resistance to resistance to 3 drug classes. These findings underscore the need for access to resistance testing and newer antiretrovirals for the optimal management of third-line ART in LMIC.

Protocol for a randomised feasibility study of Point-Of-care HIV viral load testing to Enhance Re-suppression in South Africa: the POwER study

INTRODUCTION

Access to HIV viral load testing remains difficult for many people on antiretroviral therapy (ART) in low-income and middle-income countries. Weak laboratory and clinic systems often delay the detection and management of viraemia, which can lead to morbidity, drug resistance and HIV transmission. Point-of-care testing could overcome these challenges. We aim to assess whether it is feasible to conduct a randomised trial of point-of-care viral load testing to manage viraemia.

METHODS AND ANALYSIS

We will conduct an open-label, single-site, individually randomised, feasibility study of Point-Of-care HIV viral load testing to Enhance Re-suppression, in Durban, South Africa. We will enrol approximately 100 people living with HIV who are aged ≥18 years, receiving first-line ART but with recent viraemia ≥1000 copies/mL, and randomise them 1:1 to receive point-of-care viral load or standard laboratory viral load monitoring, after 12 weeks. All participants will continue to receive care from public sector healthcare workers following South African HIV management guidelines. Participants with persistent viraemia ≥1000 copies/mL will be considered for switching to second-line ART. We will compare the proportion in each study arm who achieve the primary outcome of viral suppression <50 copies/mL at 24 weeks after enrolment. Additional outcomes include proportions retained in the study, proportions with HIV drug resistance, time to viral load results and time to switching to second-line ART. We will assess implementation of point-of-care viral load testing using process evaluation data, and through interviews and focus groups with healthcare workers.

ETHICS AND DISSEMINATION

University of Oxford Tropical Research Ethics Committee and the Biomedical Research Ethics Committee of the University of KwaZulu-Natal have approved the study. We will present results to stakeholders, and through conferences and open-access, peer-reviewed journals.

TRIAL REGISTRATION NUMBER

PACTR202001785886049.

The case for an HIV cure and how to get there

In light of the increasing global burden of new HIV infections, growing financial requirements, and shifting funding landscape, the global health community must accelerate the development and delivery of an HIV cure to complement existing prevention modalities. An effective curative intervention could prevent new infections, overcome the limitations of antiretroviral treatment, combat stigma and discrimination, and provide a sustainable financial solution for pandemic control. We propose steps to plan for an HIV cure now, including defining a target product profile and establishing the HIV Cure Africa Acceleration Partnership (HCAAP), a multidisciplinary public-private partnership that will catalyse and promote HIV cure research through diverse stakeholder engagement. HCAAP will convene stakeholders, including people living with HIV, at an early stage to accelerate the design, social acceptability, and rapid adoption of HIV-cure products.

Community acceptability of dolutegravir-based HIV treatment in women: a qualitative study in South Africa and Uganda

Background

Despite concerns about dolutegravir use in pregnancy, most low- and middle-income countries are accelerating the introduction of dolutegravir-based regimens into national antiretroviral treatment programmes. Questions remain about the acceptability of dolutegravir use in women due to the potential risks in pregnancy. This study from South Africa and Uganda explored community values, preferences and attitudes towards the use of dolutegravir-based regimens in women.

Methods

This study employed a qualitative design involving in-depth interviews and focus group discussion conducted between August 2018 to March 2019. The study was conducted in the months following an announcement of a potential risk for neural tube defects with dolutegravir use among women during conception and the first trimester. Participants included HIV positive pregnant and lactating women and their partners. They were selected purposively from urban poor communities in South Africa and Uganda. Data was analysed thematically in NVivo.

Results

Forty-four in-depth interviews and 15 focus group discussions were conducted. Most participants had positive views of dolutegravir-based regimens and perceived it to be more desirable compared with efavirenz-containing regimens. There was widespread concern about use of dolutegravir during pregnancy and among women of childbearing age due to publicity around the possible association with neural tube defects. Acceptability was gendered, with nearly all male participants preferring their female spouses of childbearing potential not to use dolutegravir, while most women not planning pregnancy wanted access to contraception alongside dolutegravir. Community awareness and knowledge of dolutegravir was low and characterised by negative information. Women were concerned about HIV-related stigma and wanted the privacy features of dolutegravir to be strengthened with modification of the pill appearance and disguised packaging.

Conclusions

Dolutegravir-based regimens were found to be generally acceptable for use in women except during pregnancy. Interest in a dolutegravir-based regimen was linked with its perceived potential to enhance health, privacy and reduce stigma while concerns about neural tube defects were the main potential barrier to dolutegravir uptake in women. In order to optimise the community acceptability and uptake of acceptability-based regimen among women it is critical to strengthen community awareness and understanding of dolutegravir treatment, improve contraception services alongside the introduction of dolutegravir, and engage with male partners.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12889-020-09991-w.

Determination of reverse transcriptase inhibitor resistance mutations in HIV-1 infected children in Côte d'Ivoire

Treatment scale-up is leading to a progressive increase in HIV resistance to antiretrovirals, especially in children. To assess resistance to reverse transcriptase inhibitors (RTIs) in HIV-1 infected children in Côte d'Ivoire, genotypic resistance tests were performed and interpreted using the ANRS algorithm (www.hivfrenchresistance.org). Phylogenetic trees were created using BioEdit v7 and Mega7 software. The frequency of resistance to at least one RTI was 79%. It was 88% for nucleoside reverse transcriptase inhibitors (NRTIs), 71% for non-nucleoside reverse transcriptase inhibitors (NNRTIs), and 63% for both classes (NRTI + NNRTI). The frequency of resistance was 50% for the ZDV + 3TC + EFV combination, 42% for the ABC + 3TC + EFV combination, and 8% for the TDF + 3TC + EFV combination. Frequently encountered resistance mutations were for NRTIs: M184V (88%), TAMs (67%), T215F/I/V/Y (33%), and L74I/V (24%); for NNRTIs: K103N/S (74%), P225H (26%), and G190A/E/Q (24%). The synthesis of phylogenetic analyses showed the predominance of the viral subtype CRF02_AG (85%). These results show a high prevalence of resistance to RTIs in children infected with HIV-1. Hence the interest of a more accessible monitoring of viral load and genotypic resistance tests in HIV-1 infected children undergoing treatment in Côte d'Ivoire.

Comparative efficacy, tolerability and safety of dolutegravir and efavirenz 400mg among antiretroviral therapies for first-line HIV treatment: A systematic literature review and network meta-analysis

BACKGROUND

To inform World Health Organization (WHO) global guidelines, we updated and expanded the evidence base to assess the comparative efficacy, tolerability, and safety of first-line antiretroviral therapy (ART) regimens.

METHODS

We searched Embase, Medline and CENTRAL on 28 February 2020 to update the systematic literature review of clinical trials comparing recommended first-line ART that informed previous WHO guidelines. Outcomes included viral suppression, change in CD4 cell counts, mortality, serious and overall adverse events (AEs), discontinuation, discontinuations due to AEs (DAEs); and new outcomes: drug-resistance, neuropsychiatric AEs, early viral suppression, weight gain and birth outcomes. Comparative effects were assessed through network meta-analyses and certainty in the evidence was assessed using the GRADE framework.

FINDINGS

We identified 156 publications pertaining to 68 trials for the primary population. Relative to efavirenz, dolutegravir had improved odds of viral suppression across all time points (odds ratio [OR]: 1·94; 95% credible interval [CrI]: 1·48-2·56 at 96 weeks); was protective of drug-resistance (OR: 0·13; 95%CrI: 0·04-0·48); and led to fewer discontinuations (OR: 0·58; 95%CrI: 0·48-0·70). Evidence supported dolutegravir use among TB-HIV co-infected persons and pregnant women. Adverse birth outcomes were observed in 33.2% of dolutegravir-managed pregnancies and 35.0% of efavirenz-managed pregnancies. Low-dose efavirenz had comparable efficacy and safety to standard-dose efavirenz, but led to fewer DAEs (OR: 0·70; 95%CrI: 0·50-0·92).

INTERPRETATION

The evidence supports choosing dolutegravir in combination with lamivudine/emtricitabine and tenofovir disoproxil fumarate as the preferred first-line regimen and low-dose efavirenz-based regimens as an alternative. Dolutegravir can be considered to be effective, safe and tolerable.

FUNDING

WHO.

Single-Cell Sequencing in Human Genital Infections

Human genital infections are one of the most concerning issues worldwide and can be categorized into sexually transmitted, urinary tract and vaginal infections. These infections, if left untreated, can disseminate to the other parts of the body and cause more complicated illnesses such as pelvic inflammatory disease, urethritis, and anogenital cancers. The effective treatment against these infections is further complicated by the emergence of antimicrobial resistance in the genital infection causing pathogens. Furthermore, the development and applications of single-cell sequencing technologies have open new possibilities to study the drug resistant clones, cell to cell variations, the discovery of acquired drug resistance mutations, transcriptional diversity of a pathogen across different infection stages, to identify rare cell types and investigate different cellular states of genital infection causing pathogens, and to develop novel therapeutical strategies. In this chapter, I will provide a complete review of the applications of single-cell sequencing in human genital infections before discussing their limitations and challenges.

Simplified dolutegravir dosing for children with HIV weighing 20 kg or more: pharmacokinetic and safety substudies of the multicentre, randomised ODYSSEY trial

BACKGROUND

Paediatric dolutegravir doses approved by stringent regulatory authorities (SRAs) for children weighing 20 kg to less than 40 kg until recently required 25 mg and 10 mg film-coated tablets. These tablets are not readily available in low-resource settings where the burden of HIV is highest. We did nested pharmacokinetic substudies in patients enrolled in the ODYSSEY-trial to evaluate simplified dosing in children with HIV.

METHODS

We did pharmacokinetic and safety substudies within the open-label, multicentre, randomised ODYSSEY trial (NCT02259127) of children with HIV starting treatment in four research centres in Uganda and Zimbabwe. Eligible children were randomised to dolutegravir in ODYSSEY and weighed 20 kg to less than 40 kg. In children weighing 20 kg to less than 25 kg, we assessed dolutegravir's pharmacokinetics in children given once daily 25 mg film-coated tablets (approved by the SRAs at the time of the study) in part one of the study, and 50 mg film-coated tablets (adult dose) or 30 mg dispersible tablets in part two of the study. In children weighing 25 kg to less than 40 kg, we also assessed dolutegravir pharmacokinetics within-subject on film-coated tablet doses of 25 mg or 35 mg once daily, which were approved by the SRAs for the children's weight band; then switched to 50 mg film-coated tablets once daily. Steady-state 24 h dolutegravir plasma concentration-time pharmacokinetic profiling was done in all enrolled children at baseline and 1, 2, 3, 4, 6, and 24 h after observed dolutegravir intake. Target dolutegravir trough concentrations (C_trough) were based on reference adult pharmacokinetic data and safety was evaluated in all children in the corresponding weight bands who consented to pharmacokinetic studies and received the studied doses.

FINDINGS

Between Sept 22, 2016, and May 31, 2018, we enrolled 62 black-African children aged from 6 years to younger than 18 years (84 pharmacokinetic-profiles). In children weighing 20 kg to less than 25 kg taking 25 mg film-coated tablets, the geometric mean (GM) C_trough (coefficient of variation) was 0·32 mg/L (94%), which was 61% lower than the GM C_trough of 0·83 mg/L (26%) in fasted adults on dolutegravir 50 mg once-daily; in children weighing 25 kg to less than 30 kg taking 25 mg film-coated tablets, the GM C_trough was 0·39 mg/L (48%), which was 54% lower than the GM C_trough in fasted adults; and in those 30 kg to less than 40 kg taking 35 mg film-coated tablets the GM C_trough was 0·46 mg/L (63%), which was 45% lower than the GM C_trough in fasted adults. On 50 mg film-coated tablets or 30 mg dispersible tablets, C_trough was close to the adult reference (with similar estimates on the two formulations in children in the 20 to <25 kg weight band), with total exposure (area under the concentration-time curve from 0 h to 24 h) in between reference values in adults dosed once and twice daily, where safety data are reassuring, although maximum concentrations were higher in children weighing 20 kg to less than 25 kg than in the twice-daily adult reference. Over a 24-week follow-up period in 47 children on 30 mg dispersible tablets or 50 mg film-coated tablets, none of the three reported adverse events (cryptococcal meningitis, asymptomatic anaemia, and asymptomatic neutropenia) were considered related to dolutegravir.

INTERPRETATION

Adult dolutegravir 50 mg film-coated tablets given once daily provide appropriate pharmacokinetic profiles in children weighing 20 kg or more, with no safety signal, allowing simplified practical dosing and rapid access to dolutegravir. These results informed the WHO 2019 dolutegravir paediatric dosing guidelines and have led to US Food and Drug Administration approval of adult dosing down to 20 kg.

FUNDING

Paediatric European Network for Treatment of AIDS Foundation, ViiV Healthcare, UK Medical Research Council.

Engendering health systems in response to national rollout of dolutegravir-based regimens among women of childbearing potential: a qualitative study with stakeholders in South Africa and Uganda

Background

In the era of rapid dolutegravir rollout, concerns about neural tube defects have complicated the health systems response among women of childbearing potential. This qualitative study, which was nested within the DolPHIN-2 clinical trial, examined the current and future health system opportunities and challenges associated with the transition to dolutegravir-based regimen as first line antiretroviral therapy among women of childbearing potential in South Africa and Uganda.

Method

Semi-structured in-depth interviews with members of antiretroviral therapy guideline development groups and affiliates were conducted. Thirty-one participants were purposively selected for the study, including senior officials from the Ministry of Health and National Drug Regulatory Authority in Uganda and South Africa as well as health-sector development partners, activists, researchers and health workers. A thematic approach was used to analyse the data.

Findings

Despite differences in health system contexts, several common challenges and opportunities were identified with the transition among women of childbearing potential in South Africa and Uganda. In both contexts national stakeholders identified challenges with ensuring gender equity in roll out due to the potential teratogenicity of dolutegravir, paucity of data on dolutegravir use in pregnancy, potential stock out of effective contraceptives, poorly integrated contraception services, and limited pharmacovigilance in pregnancy. Participants identified opportunities that could be harnessed to accelerate the transition, including high stakeholder interest and commitment to transition, national approval and licensure of a generic tenofovir/lamivudine/dolutegravir regimen, availability of a network of antiretroviral therapy providers, and strong desire among women for newer and more tolerable regimens.

Conclusion

The transition to dolutegravir-based regimens has the potential to strengthen health systems in low- and middle-income countries to engender equitable access to optimised antiretroviral regimen among women. There is the need for a multi-sectoral effort to harness the opportunities of the health systems to addresses the bottlenecks to the transition and initiate extensive community engagement alongside individual and institutional capacity strengthening. Improvements in pregnancy pharmacovigilance and counselling and family planning services are critical to ensuring a successful transition among women of childbearing potential.

The crosstalk between antiretrovirals pharmacology and HIV drug resistance

INTRODUCTION

The clinical development of antiretroviral drugs has been followed by a rapid and concomitant development of HIV drug resistance. The development and spread of HIV drug resistance is due on the one hand to the within-host intrinsic HIV evolutionary rate and on the other to the wide use of low genetic barrier antiretrovirals.

AREAS COVERED

We searched PubMed and Embase on 31 January 2020, for studies reporting antiretroviral resistance and pharmacology. In this review, we assessed the molecular target and mechanism of drug resistance development of the different antiretroviral classes focusing on the currently approved antiretroviral drugs. Then, we assessed the main pharmacokinetic/pharmacodynamic of the antiretrovirals. Finally, we retraced the history of antiretroviral treatment and its interconnection with antiretroviral worldwide resistance development both in , and middle-income countries in the perspective of 90-90-90 World Health Organization target.

EXPERT OPINION

Drug resistance development is an invariably evolutionary driven phenomenon, which challenge the 90-90-90 target. In high-income countries, the antiretroviral drug resistance seems to be stable since the last decade. On the contrary, multi-intervention strategies comprehensive of broad availability of high genetic barrier regimens should be implemented in resource-limited setting to curb the rise of drug resistance.

Modulation of mTORC1 Signaling Pathway by HIV-1

Mammalian target of rapamycin complex 1 (mTORC1) is a master regulator of cellular proliferation and survival which controls cellular response to different stresses, including viral infection. HIV-1 interferes with the mTORC1 pathway at every stage of infection. At the same time, the host cells rely on the mTORC1 pathway and autophagy to fight against virus replication and transmission. In this review, we will provide the most up-to-date picture of the role of the mTORC1 pathway in the HIV-1 life cycle, latency and HIV-related diseases. We will also provide an overview of recent trends in the targeting of the mTORC1 pathway as a promising strategy for HIV-1 eradication.

Zimbabwe's national third-line antiretroviral therapy program: Cohort description and treatment outcomes

Background

In 2015, Zimbabwe introduced third-line antiretroviral therapy (ART) through four designated treatment centers; three government clinics in Harare and Bulawayo, and Newlands Clinic (NC), operated by a private voluntary organization in Harare. We describe characteristics of patients receiving third line ART and analyzed treatment outcomes in this national programme as of 31 December 2018.

Methods

We described the population using proportions for categorical variables, and medians and interquartile ranges for continuous variables. Patients from NC, where data were more complete, were followed from the date of starting third-line ART until death, transfer, loss to follow up or 31 December 2018.

Results

A total of 209 patients had ever received third-line ART: 124 at NC and 85 from the three government clinics. HIV genotype results were available for 89 (72%) patients at NC and fourteen (16.5%) patients in the government clinics. Median duration of third line ART (years) in the government clinics was 2.3 (IQR:0.6–3.4), 1.3 (IQR: 0.7–1.7) and 1 (0.6–1.9). Of the 67 patients who received third line ART in the government clinics for at least six months, 53 (79%) had most recent viral load (VL) < 1000 copies/ml. Data on other treatment outcomes from government clinics were incomplete.

From NC: a total of 109 (88%) patients were still in care, 13 (10.5%) had died and 2 (1.5%) were transferred. Median duration of third-line ART was 1.4 years (IQR: 0.6–2.8). Among the 111 NC patients who had received third-line ART for at least 6 months, 83 (75%) had a VL <50 copies/ml and 106 (95.5%) had a VL <1000 copies/ml.

Conclusion

Our findings demonstrate that, with comprehensive care, patients failing second-line ART can achieve high rates of virological suppression on third-line regimens. There is need to decentralize the provision of third-line ART in Zimbabwe. More needs to be done to improve completeness of data in the government clinics.

HIV drug resistance in a cohort of HIV-infected MSM in the United States

OBJECTIVE

To analyze HIV drug resistance among MSM recruited for participation in the HPTN 078 study, which evaluated methods for achieving and maintaining viral suppression in HIV-infected MSM.

METHODS

Individuals were recruited at four study sites in the United States (Atlanta, Georgia; Baltimore, Maryland; Birmingham, Alabama; and Boston, Massachusetts; 2016-2017). HIV genotyping was performed using samples collected at study screening or enrollment. HIV drug resistance was evaluated using the Stanford v8.7 algorithm. A multiassay algorithm was used to identify individuals with recent HIV infection. Clustering of HIV sequences was evaluated using phylogenetic methods.

RESULTS

High-level HIV drug resistance was detected in 44 (31%) of 142 individuals (Atlanta: 21%, Baltimore: 29%, Birmingham: 53%, Boston: 26%); 12% had multiclass resistance, 16% had resistance to tenofovir or emtricitabine, and 8% had resistance to integrase strand transfer inhibitors (INSTIs); 3% had intermediate-level resistance to second-generation INSTIs. In a multivariate model, self-report of ever having been on antiretroviral therapy (ART) was associated with resistance (P = 0.005). One of six recently infected individuals had drug resistance. Phylogenetic analysis identified five clusters of study sequences; two clusters had shared resistance mutations.

CONCLUSION

High prevalence of drug resistance was observed among MSM. Some had multiclass resistance, resistance to drugs used for preexposure prophylaxis (PrEP), and INSTI resistance. These findings highlight the need for improved HIV care in this high-risk population, identification of alternative regimens for PrEP, and inclusion of integrase resistance testing when selecting ART regimens for MSM in the United States.

Challenges of HIV diagnosis and management in the context of pre-exposure prophylaxis (PrEP), post-exposure prophylaxis (PEP), test and start and acute HIV infection: a scoping review

INTRODUCTION

Knowledge of HIV status relies on accurate HIV testing, and is the first step towards access to HIV treatment and prevention programmes. Globally, HIV-status unawareness represents a significant challenge for achieving zero new HIV infections and deaths. In order to enhance knowledge of HIV status, the World Health Organisation (WHO) recommends a testing strategy that includes the use of HIV-specific antibody point-of-care tests (POCT). These POCTs do not detect acute HIV infection, the stage of disease when viral load is highest but HIV antibodies are undetectable. Complicating things further, in the presence of antiretroviral therapy (ART) for pre-exposure prophylaxis (PrEP) or post-exposure prophylaxis (PEP), other currently available testing technologies, such as viral load detection for diagnosis of acute HIV infection, may yield false-negative results. In this scoping review, we evaluate the evidence and discuss alternative HIV testing algorithms that may mitigate diagnostic dilemmas in the setting of increased utilization of ART for immediate treatment and prevention of HIV infection.

DISCUSSION

Missed acute HIV infection prevents people living with HIV (PLHIV) from accessing early treatment, increases likelihood of onward transmission, and allows for inappropriate initiation or continuation of PrEP, which may result in HIV drug resistance. While immediate ART is recommended for all PLHIV, studies have shown that starting ART in the setting of acute HIV infection may result in a delayed or complete absence of development of HIV-specific antibodies, posing a diagnostic challenge that is particularly pertinent to resource-limited, high HIV burden settings where HIV-antibody POCTs are standard of care. Similarly, ART used as PrEP or PEP may supress HIV RNA viral load, complicating current HIV testing algorithms in resource-wealthy settings where viral detection is included. As rollout of PrEP continues, HIV testing algorithms may need to be modified.

CONCLUSIONS

With increasing use of PrEP and ART in acute infection we anticipate diagnostic challenges using currently available HIV testing strategies. Research and surveillance are needed to determine the most appropriate assays and optimal testing algorithms that are accurate, affordable and sustainable.

Prevalence and Correlates of Pre-Treatment HIV Drug Resistance among HIV-Infected Children in Ethiopia

Pediatric human immunodeficiency virus (HIV) care in resource-limited settings remains a major challenge to achieving global HIV treatment and virologic suppression targets, in part because the administration of combination antiretroviral therapies (cART) is inherently complex in this population and because viral load and drug resistance genotyping are not routinely available in these settings. Children may also be at elevated risk of transmission of drug-resistant HIV as a result of suboptimal antiretroviral administration for prevention of mother-to-child transmission. We investigated the prevalence and the correlates of pretreatment HIV drug resistance (PDR) among HIV-infected, cART-naive children in Ethiopia. We observed an overall PDR rate of 14%, where all cases featured resistance to non-nucleoside reverse transcriptase inhibitors (NNRTIs): ~9% of participants harbored resistance solely to NNRTIs while ~5% harbored resistance to both NNRTIs and nucleoside reverse transcriptase inhibitors (NRTIs). No resistance to protease inhibitors was observed. No sociodemographic or clinical parameters were significantly associated with PDR, though limited statistical power is noted. The relatively high (14%) rate of NNRTI resistance in cART-naive children supports the use of non-NNRTI-based regimens in first-line pediatric treatment in Ethiopia and underscores the urgent need for access to additional antiretroviral classes in resource-limited settings.

Transmitted drug resistance in newly diagnosed and treatment-naïve HIV type 1-infected patients in Hungary

OBJECTIVES

Transmitted human immunodeficiency virus type 1 (HIV-1) drug resistance (TDR) may affect the success of first-line antiretroviral treatment. This study aimed to monitor the presence of HIV-1 strains carrying transmitted drug resistance-associated mutations (TDRMs) in newly diagnosed and treatment-naïve patients in Hungary.

METHODS

This study included 168 HIV-infected individuals diagnosed between 2013-2017; most of them (93.5%) belonged to the homo/bisexual population. HIV-1 subtypes and TDRMs were determined by analysing the protease and reverse transcriptase coding regions of the pol gene by the Stanford HIV Drug Resistance Database. Transmission clusters among patients were identified using phylogenetic analysis.

RESULTS

Although subtype B HIV-1 strains were predominant (87.5%), non-B subtypes including F, A, CRF01_AE, CRF02_AG, D and G were also recorded, especially in young adults. The overall prevalence of TDR was 10.7% (18 of 168; 95% CI: 6.9-16.3%). Subtype B HIV-1 strains carried most of the TDRMs (94.4%). Nucleoside reverse transcriptase inhibitor (NRTI)-associated mutations were the most prevalent indicators of TDR (16 of 168; 9.5%; 95% CI: 5.9-14.9%), followed by mutations conferring resistance to non-nucleoside reverse transcriptase inhibitors (NNRTIs) (2 of 168; 1.2%; 95% CI: 0.3-4.2%) and protease inhibitors (PIs) (1 of 168, 0.6%; 95% CI: 0.1-3.3%). Phylogenetic analysis revealed that most NRTI-associated resistance mutations were associated with a single monophyletic clade, suggesting early single-source introduction and ongoing spread of this drug-resistant HIV-1 strain.

CONCLUSIONS

Onward transmission of drug-resistant subtype B HIV-1 strains accounted for the majority of TDRs observed among treatment-naïve HIV-infected individuals in Hungary.