High Levels of Dual-Class Drug Resistance in HIV-Infected Children Failing First-Line Antiretroviral Therapy in Southern Ethiopia

Virological Non-Suppression among Newly Diagnosed HIV-Positive Individuals on Dolutegravir-Based Antiretroviral Treatment in Eastern Ethiopia: Follow-Up Study

There have been limited studies linking baseline factors, including the viral load (VL) test, with virological non-suppression since the introduction of dolutegravir (DTG)-based regimens as first-line antiretroviral treatment (ART) in Ethiopia. This study aimed to identify baseline factors associated with virological non-suppression between October 2020 and July 2022. A follow-up study was conducted in eastern Ethiopia among newly diagnosed people living with HIV (PLHIV). A questionnaire and a checklist were used to collect the data. Five milliliters of venous blood were obtained at baseline and six months to determine the VL. A VL test was performed using the Abbott RealTime HIV-1 assay. To determine predictors of virological non-suppression, bivariate and multivariate logistic regression analyses were used. There were 235 PLHIV enrolled, 70.6% of whom were female, with a mean age of 33.9 years. Of the 161 retained on ART, virological non-suppression was 8.7% at six months. Baseline predictors of virological non-suppression were age ≤ 30 years, a history of substance use, and a VL greater than 4-log10 copies/mL. In this cohort, virological non-suppression was found to be optimal but still lagged slightly behind the third 95%-target. Thus, targeted interventions, the introduction of baseline VL testing to improve treatment outcomes, and fostering the attainment of UNAIDS 95-95-95 targets are recommended. Furthermore, broader research is recommended to explore the reasons for virological non-suppression in the study area.

Full-spectrum HIV drug resistance mutation detection by high-resolution complete pol gene sequencing

BACKGROUND

Drug resistance mutation testing is a key element for HIV clinical management, informing effective treatment regimens. However, resistance screening in current clinical practice is limited in reporting linked cross-class resistance mutations and minority variants, both of which may increase the risk of virological failure.

METHODS

To address these limitations, we obtained 358 full-length pol gene sequences from 52 specimens of 20 HIV infected individuals by combining microdroplet amplification, unique molecular identifier (UMI) labeling, and long-read high-throughput sequencing.

RESULTS

We conducted a rigorous assessment of the accuracy of our pipeline for precision drug resistance mutation detection, verifying that a sequencing depth of 35 high-throughput reads achieved complete, error-free pol gene sequencing. We detected 26 distinct drug resistance mutations to Protease Inhibitors (PIs), Nucleoside Reverse Transcriptase Inhibitors (NRTIs), Non-Nucleoside Reverse Transcriptase Inhibitors (NNRTIs), and Integrase Strand Transfer Inhibitors (INSTIs). We detected linked cross-class drug resistance mutations (PI+NRTI, PI+NNRTI, and NRTI+NNRTI) that confer cross-resistance to multiple drugs in different classes. Fourteen different types of minority mutations were also detected with frequencies ranging from 3.2% to 19%, and the presence of these mutations was verified by Sanger reference sequencing. We detected a putative transmitted drug resistance mutation (TDRM) in one individual that persisted for over seven months from the first sample collected at the acute stage of infection prior to seroconversion.

CONCLUSIONS

Our comprehensive drug resistance mutation profiling can advance clinical practice by reporting mutation linkage and minority variants to better guide antiretroviral therapy options.

Predictors of Efavirenz Plasma Exposure, Auto-Induction Profile, and Effect of Pharmacogenetic Variations among HIV-Infected Children in Ethiopia: A Prospective Cohort Study

(1) Background: Efavirenz plasma concentration displays wide between-patient variability partly due to pharmacogenetic variation and autoinduction. Pediatric data on efavirenz pharmacokinetics and the relevance of pharmacogenetic variation are scarce, particularly from sub-Saharan Africa, where >90% of HIV-infected children live and population genetic diversity is extensive. We prospectively investigated the short- and long-term effects of efavirenz auto-induction on plasma drug exposure and the influence of pharmacogenetics among HIV-infected Ethiopian children. (2) Method: Treatment-naïve HIV-infected children aged 3-16 years old (n = 111) were enrolled prospectively to initiate efavirenz-based combination antiretroviral therapy (cART). Plasma efavirenz concentrations were quantified at 4, 8, 12, 24, and 48 weeks of cART. Genotyping for CYP2B6, CYP3A5, UGT2B7, ABCB1, and SLCO1B1 common functional variant alleles was performed. (3) Results: The efavirenz plasma concentration reached a peak at two months, declined by the 3rd month, and stabilized thereafter, with no significant difference in geometric mean over time. On average, one-fourth of the children had plasma efavirenz concentrations ≥4 µg/mL. On multivariate analysis, CYP2B6*6 and ABCB1c.3435 C > T genotypes and low pre-treatment low-density lipoprotein (LDL) were significantly associated with higher plasma efavirenz concentration regardless of treatment duration. Duration of cART, sex, age, nutritional status, weight, and SLCO1B, CYP3A5, UGT2B7, and ABCB1 rs3842 genotypes were not significant predictors of efavirenz plasma exposure. (4) Conclusion: Pre-treatment LDL cholesterol and CYP2B6*6 and ABCB1c.3435 C > T genotypes predict efavirenz plasma exposure among HIV-infected children, but treatment-duration-dependent changes in plasma efavirenz exposure due to auto-induction are not statistically significant.

Predictors of Virologic Failure Among a Cohort of HIV-infected Children in Southern Ethiopia

BACKGROUND

Optimal care for children with HIV infection includes timely assessment of treatment failure. Using HIV viral load to define treatment failure remains a challenge in resource-limited settings.

METHODS

Children with HIV infection who were already on or starting first-line antiretroviral therapy were enrolled and followed over time. We examined clinical and immunologic predictors of virologic failure (VF), defined as consecutive viral load measurements > 1000 copies/mL (VF). Children were followed every 6 months with clinical assessments, immunologic assays and viral load testing until treatment failure or up to 18 months.

RESULTS

Of the 484 children with complete data, we observed a prevalence of 15% who had VF at enrollment, and 18 who developed VF over 10.5 person-years of follow-up for an incidence of 4.97 [95% CI: 3.04-7.70) per 100 person-years. Lower adherence, lower CD4 T-cell count, lower white blood cells count, lower platelets and a lower glomerular filtration rate were all associated with increased VF. However, in a multivariable analysis, renal function (estimated glomerular filtration rate < 90 mL/min), odds ratio: 11.5 (95% CI: 1.5-63.7), and lower adherence, odds ratio: 3.9 (95% CI: 1.1-13.4), were the only factors associated with development of VF.

CONCLUSIONS

We identified a significant risk of VF in children with HIV infection in a prospective cohort study in southern Ethiopia and limited predictive value of clinical variables for VF. This provides further evidence that rapid and reliable viral load testing is needed to adequately address the HIV epidemic, along with implementation of adherence interventions in sub-Saharan Africa.

High predictive efficacy of integrase strand transfer inhibitors in perinatally HIV-1-infected African children in therapeutic failure of first- and second-line antiretroviral drug regimens recommended by the WHO

Objectives

The predictive efficacy of integrase (IN) strand transfer inhibitors (INSTIs) was investigated in HIV-infected children born to HIV-infected mothers in Africa.

Methods

Plasma was collected at the Complexe Pédiatrique of Bangui, Central African Republic, from INSTI-naive children (n = 8) and adolescents (n = 10) in virological failure (viral load >1000 copies/mL) after 5 years of first- and/or second-line combination ART (cART). IN, reverse transcriptase (RT) and protease (P) genes were genotyped and drug resistance mutations (DRMs) to INSTIs, NRTIs, NNRTIs and PIs were interpreted using the Stanford algorithm.

Results

Successful IN, RT and P genotypes were obtained for 18, 13 and 15 children (median age 11 years, range 5–18; 8 were female), respectively. Two (2/18; 11.1%) viruses from children treated with a first-line regimen had INSTI DRMs at codon 138 (E138K and E138T), which is known to harbour major resistance mutations, and also had the accessory mutations L74I, G140K, G140R and G163R. The majority (16/18; 88.9%) of HIV-1 IN sequences demonstrated full susceptibility to all major INSTIs with a high frequency of natural polymorphic mutations. Most (12/15; 80%) genotyped viruses harboured at least one major DRM conferring resistance to at least one of the WHO-recommended antiretroviral drugs (NNRTIs, NRTIs and PIs) prescribed in first- and second-line regimens.

Conclusions

INSTIs could be proposed in first-line regimens in the majority of African children or adolescents and may constitute relevant therapeutic alternatives as second- and third-line cART regimens in HIV-infected children and adolescents living in sub-Saharan Africa.

Rates and Correlates of Short Term Virologic Response among Treatment-Naïve HIV-Infected Children Initiating Antiretroviral Therapy in Ethiopia: A Multi-Center Prospective Cohort Study

There is limited data on virologic outcome and its correlates among HIV-infected children in resource-limited settings. We investigated rate and correlates of virologic outcome among treatment naïve HIV-infected Ethiopian children initiating cART, and were followed prospectively at baseline, 8, 12, 24 and 48 weeks using plasma viral load, clinical examination, laboratory tests and pretreatment HIV drug resistance (PDR) screening. Virologic outcome was assessed using two endpoints–virological suppression defined as having “undetectable” plasma viral load < 150 RNA copies/mL, and rebound defined as viral load ≥150 copies/mL after achieving suppression. Cox Proportional Hazards Regression was employed to assess correlates of outcome. At the end of follow up, virologic outcome was measured for 110 participants. Overall, 94(85.5%) achieved virological suppression, of which 36(38.3%) experienced virologic rebound. At 48 weeks, 9(8.2%) children developed WHO-defined virological treatment failure. Taking tenofovir-containing regimen (Hazard Ratio (HR) 3.1-[95% confidence interval (95%CI) 1.0–9.6], p = 0.049) and absence of pretreatment HIV drug resistance (HR 11.7-[95%CI 1.3–104.2], p = 0.028) were independently associated with earlier virologic suppression. In conclusion, PDR and cART regimen type correlate with rate of virologic suppression which was prominent during the first year of cART initiation. However, the impact of viral rebound in 38.3% of the children needs evaluation.

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.

A viral genome wide association study and genotypic resistance testing in patients failing first line antiretroviral therapy in the first large countrywide Ethiopian HIV cohort

BACKGROUND

Antiretroviral therapy (ART) was rolled-out in Ethiopia in 2005, but there are no reports on outcome of ART and human immunodeficiency virus drug resistance (HIVDR) at national level. We described acquired drug resistance mutations in pol gene and performed a viral genome wide association study in virologic treatment failure patients who started first line ART during 2009-2011 in the first large countrywide HIV cohort in Ethiopia.

METHODS

The outcome of tenofovir (TDF)- and zidovudine (ZDV)-based ART was defined in 874 ART naïve patients using the on-treatment (OT) and intention-to-treat (ITT) analyses. Genotypic resistance testing was done in patients failing ART (> 1000 copies/ml) at month 6 and 12. Near full-length genome sequencing (NFLG) was used to assess amino acid changes in HIV-1 gag, pol, vif, vpr, tat, vpu, and nef genes between paired baseline and month 6 samples.

RESULTS

High failure rates were found in ITT analysis at month 6 and 12 (23.3%; 33.9% respectively). Major nucleoside and non-nucleoside reverse transcriptase (NRTI/NNRTI) drug resistance mutations were detected in most failure patients at month 6 (36/47; 77%) and month 12 (20/30; 67%). A high rate of K65R was identified only in TDF treated patients (35.7%; 50.0%, respectively). No significant difference was found in failure rate or extent of HIVDR between TDF- and ZDV- treated patients. All target regions of interest for HIVDR were described by NFLG in 16 patients tested before initiation of ART and at month 6.

CONCLUSION

In this first Ethiopian national cohort, a high degree of HIVDR was seen among ART failure patients, independent on whether TDF- or ZDV was given. However, the major reason to ART failure was lost-to-follow-up rather than virologic failure. Our NFLG assay covered all relevant target genes for antiretrovirals and is an attractive alternative for HIVDR surveillance.

Antiretroviral Resistance Patterns in Children with HIV Infection

PURPOSE OF REVIEW

To provide an update on the patterns of HIV drug resistance in children, including pretreatment drug resistance (PDR) and acquired drug resistance (ADR), focusing on children in low- and middle-income countries (LMICs) for whom empiric first-line (FL) and second-line (SL) antiretroviral regimens are usually recommended.

RECENT FINDINGS

High levels of PDR, particularly to non-nucleoside reverse transcriptase inhibitors (NNRTIs), and poor treatment outcomes on NNRTI-based FL antiretroviral therapy (ART) have been widely reported among infants and young children. There is a paucity of recent data on the use of protease inhibitor (PI)-based FL and SL regimens in children, but studies have reported poor tolerability, adherence problems and the development of PI resistance. Limited access to virological monitoring and HIV drug resistance testing contributes to delays in identifying treatment failure due to ADR and delays in switching to SL regimens in children. Implementation of FL ART regimens that have a higher barrier to developing resistance and are safe and well tolerated is required in order to attain global treatment targets. Although PI-based regimens may be effective as FL or SL treatment in children, lack of appropriate formulations leading to poor tolerability, drug-drug interactions, and cost considerations have negatively impacted their use among children in LMICs. There is hope that dolutegravir-based regimens recommended for children by the World Health Organization will be widely implemented once child-friendly formulations are available, and dosing and safety studies currently underway are completed, and that this will significantly improve treatment outcomes.

An evaluation of elvitegravir plus cobicistat plus tenofovir alafenamide plus emtricitabine as a single-tablet regimen for the treatment of HIV in children and adolescents

INTRODUCTION

Approximately 2.1 million of the estimated 36 million infected with HIV are children or adolescents. International guidelines for HIV-1 Infection suggest starting antiretrovirals (ARV) at the moment of diagnosis. Many factors limit the optimization of antiretroviral therapy in children and adolescents: lack of pediatric formulations, poor adherence, metabolic and pharmacokinetic changes associated withnormal child development and puberty. Areas covered: Three integrase inhibitors are approved by the US Food and Drug Administration and by European Medical Agency for children and adolescents with HIV-1 infection. Raltegravir is approved for children aged 4 weeks to 18 years, while dolutegravir and elvitegravir co-formulated with cobicistat, emtricitabine, and tenofovir alafenamide (E/C/FTC/TAF) are approved for children from 6 years of age. This article evaluates E/C/FTC/TAF as a treatment option. Expert opinion: E/C/FTC/TAF was well tolerated, and the antiretroviral activity and tolerability data of this combination support the use in children and adolescents. However, the studies regarding E/C/FTC/TAF in children and adolescents are scant. Consequently, additional studies investigating its safety and efficacy in children are paramount.