Long-term virologic response and genotypic resistance mutations in HIV-1 infected Kenyan children on combination antiretroviral therapy

HIV Drug Resistance Patterns and Characteristics Associated with Clinically Significant Drug Resistance among Children with Virologic Failure on Antiretroviral Treatment in Kenya: Findings from the Opt4Kids Randomized Controlled Trial

Increasing HIV drug resistance (DR) among children with HIV (CHIV) on antiretroviral treatment (ART) is concerning. CHIV ages 1-14 years enrolled from March 2019 to December 2020 from five facilities in Kisumu County, Kenya, were included. Children were randomized 1:1 to control (standard-of-care) or intervention (point-of-care viral load (POC VL) testing every three months with targeted genotypic drug resistance testing (DRT) for virologic failure (VF) (≥1000 copies/mL)). A multidisciplinary committee reviewed CHIV with DRT results and offered treatment recommendations. We describe DR mutations and present logistic regression models to identify factors associated with clinically significant DR. We enrolled 704 children in the study; the median age was 9 years (interquartile range (IQR) 7, 12), 344 (49%) were female, and the median time on ART was 5 years (IQR 3, 8). During the study period, 106 (15%) children had DRT results (84 intervention and 22 control). DRT detected mutations associated with DR in all participants tested, with 93 (88%) having major mutations, including 51 (54%) with dual-class resistance. A history of VF in the prior 2 years (adjusted odds ratio (aOR) 11.1; 95% confidence interval (CI) 6.3, 20.0) and less than 2 years on ART at enrollment (aOR 2.2; 95% CI 1.1, 4.4) were associated with increased odds of major DR. DR is highly prevalent among CHIV on ART with VF in Kenya. Factors associated with drug resistance may be used to determine which children should be prioritized for DRT.

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.

Prevalence and predictors of virological failure in pediatric patients on HAART in sub-Saharan Africa: a systematic review and meta-analysis

Antiretroviral treatment failure has emerged as a challenge in the management of pediatric human immunodeficiency virus (HIV) patients, especially in resource-limited countries despite accessibility to Highly Active Antiretroviral Therapy (HAART). A systematic review and meta-analysis was conducted to synthesize virological failure (VF) prevalence and ascertain its predictors in children in sub-Saharan Africa. An electronic database search strategy was conducted from January to September 2021 on PubMed, EMBASE, SCOPUS, HINARI, and CINAHL. Further, manual searching was conducted on non-indexed journals. Utilizing the JASP© version 0.17.2 (2023) statistical software, a meta-analysis of pooled prevalence of VF was estimated using the standardized mean differences. Further, selection models were used to assess the risk of bias and heterogeneity. The pooled odds ratios were estimated for the respective studies reporting on predictors of VF. The overall pooled estimate of the prevalence of VF in sub-Saharan Africa among the sampled population was 29% (95% CI: 27.0-32.0; p<0.001). Predictors of VF were drug resistance (OR: 1.68; 95% CI: 0.88-2.49; p < 0.001), poor adherence (OR: 5.35; 95% CI: 5.26-5.45; p < 0.001), nevirapine (NVP)-based regimen (OR: 5.11; 95% CI: 4.66-5.56; p < 0.001), non-usage of cotrimoxazole prophylaxis (OR: 4.30; 95% CI: 4.13-4.47; p < 0.001), higher viral load at the initiation of antiretroviral therapy (ART) (OR: 244.32; 95% CI: 244.2-244.47; p <0.001), exposure to the prevention of mother to child transmission (PMTCT) (OR: 8.02; 95%CI: 7.58-8.46; p < 0.001), increased age/older age (OR: 3.37; 95% CI: 2.70-4.04; p < 0.001), advanced World Health Organization (WHO) stage (OR: 6.57; 95% CI: 6.17-6.98; p < 0.001), not having both parents as primary caregivers (OR: 3.01; 95% CI: 2.50-3.53; p < 0.001), and tuberclosis (TB) treatment (OR: 4.22; 95% CI: 3.68-4.76; p <0.001). The mean VF prevalence documented is at variance with studies in other developing countries outside the sub-Saharan region. The high prevalence of HIV cases contrasting with the limited expertise in the management of pediatric ART patients could explain this variance.

Prevalence and factors associated with pediatric HIV therapy failure in a tertiary hospital in Asmara, Eritrea: A 15-year retrospective cohort study

INTRODUCTION

Treatment failure (TF) in HIV infected children is a major concern in resource-constrained settings in Sub-Saharan Africa (SSA). This study investigated the prevalence, incidence, and factors associated with first-line cART failure using the virologic (plasma viral load), immunologic and clinical criteria among HIV-infected children.

METHODS

A retrospective cohort study of children (<18 years of age on treatment for a period of > 6 months) enrolled in the pediatric HIV/AIDs treatment program at Orotta National Pediatric Referral Hospital from January 2005 to December 2020 was conducted. Data were summarized using percentages, medians (± interquartile range (IQR)), or mean ± standard deviation (SD). Where appropriate, Pearson Chi-Squire (χ2) tests or Fishers exacts test, Kaplan-Meier (KM) estimates, and unadjusted and adjusted Cox-proportional hazard regression models were employed.

RESULTS

Out of 724 children with at least 24 weeks' follow-up 279 experienced therapy failure (TF) making prevalence of 38.5% (95% CI 35-42.2) over a median follow-up of 72 months (IQR, 49-112 months), with a crude incidence of failure of 6.5 events per 100- person-years (95% CI 5.8-7.3). In the adjusted Cox proportional hazards model, independent factors of TF were suboptimal adherence (Adjusted Hazard Ratio (aHR) = 2.9, 95% CI 2.2-3.9, p < 0.001), cART backbone other than Zidovudine and Lamivudine (aHR = 1.6, 95% CI 1.1-2.2, p = 0.01), severe immunosuppression (aHR = 1.5, 95% CI 1-2.4, p = 0.04), wasting or weight for height z-score < -2 (aHR = 1.5, 95% CI 1.1-2.1, p = 0.02), late cART initiation calendar years (aHR = 1.15, 95% CI 1.1-1.3, p < 0.001), and older age at cART initiation (aHR = 1.01, 95% CI 1-1.02, p < 0.001).

CONCLUSIONS

Seven in one hundred children on first-line cART are likely to develop TF every year. To address this problem, access to viral load tests, adherence support, integration nutritional care into the clinic, and research on factors associated with suboptimal adherence should be prioritized.

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

BACKGROUND

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

SETTING

Academic Model Providing Access to Healthcare, western Kenya.

METHODS

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

RESULTS

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

CONCLUSION

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

Virologic failure and switch to second-line antiretroviral therapy in children with HIV in Lilongwe, Malawi: an observational cohort study

BACKGROUND

As routine viral load testing among HIV-infected individuals on antiretroviral therapy (ART) expands, virologic failure (VF) among children in developing countries remains poorly understood. We assessed the rate of VF, the proportion failing who were subsequently switched to second-line ART and factors associated with VF among children ≤18 y.

METHODS

An observation cohort study among 1312 children at two public clinics in Lilongwe, Malawi who initiated a first-line ART regimen between January 2014 and December 2017 and remained on treatment for ≥6 mo was conducted. Kaplan-Meier methods estimated the probabilities of VF. Univariable and multivariable Poisson regression models were used to explore predictors of VF.

RESULT

Overall, 16% (208/1312) of children experienced VF with an incidence rate of 10.1 events per 100 person-years. Of the 208, 184 (88%) were switched to second-line ART: 68 (43%) switched the same day VF was confirmed and 106 (66%) switched within 90 d of confirmed VF. Use of a Nevirapine (NVP)-based regimen and initiating ART in 2016-2017 compared with 2014-2015 were independent predictors of VF.

CONCLUSION

VF is common among children receiving ART. The findings suggest that VF can be reduced by phasing out NVP-based regimen and by ensuring optimal adherence to ART.

Optimizing viral load suppression in Kenyan children on antiretroviral therapy (Opt4Kids)

Background

As many as 40% of the 1 million children living with HIV (CLHIV) receiving antiretroviral treatment (ART) in resource limited settings have not achieved viral suppression (VS). Kenya has a large burden of pediatric HIV with nearly 140,000 CLHIV. Feasible, scalable, and cost-effective approaches to ensure VS in CLHIV are urgently needed. The goal of this study is to determine the feasibility and impact of point-of-care (POC) viral load (VL) and targeted drug resistance mutation (DRM) testing to improve VS in children on ART in Kenya.

Methods

We are conducting a randomized controlled study to evaluate the use of POC VL and targeted DRM testing among 704 children aged 1-14 years on ART at health facilities in western Kenya. Children are randomized 1:1 to intervention (higher frequency POC VL and targeted DRM testing) vs. control (standard-of-care) arms and followed for 12 months. Our primary outcome is VS (VL < 1000 copies/mL) 12 months after enrollment by study arm. Secondary outcomes include time to VS and the impact of targeted DRM testing on VS. In addition, key informant interviews with patients and providers will generate an understanding of how the POC VL intervention functions. Finally, we will model the cost-effectiveness of POC VL combined with targeted DRM testing.

Discussion

This study will provide critical information on the impact of POC VL and DRM testing on VS among CLHIV on ART in a resource-limited setting and directly address the need to find approaches that maximize VS among children on ART.

Trials registration

NCT03820323.

Drug resistance in HIV-infected children living in rural South Africa: Implications of an antiretroviral therapy initiated during the first year of life

INTRODUCTION

Management of antiretroviral-drug resistance in HIV-infected children is a global health concern. We compared the long-term virological outcomes of two cohorts of children living in a rural setting of South Africa. The first cohort initiated treatment before one year and the second after two years of age. The aim of this study was to describe the long-term consequences of early treatment initiation in terms of viral load and drug-resistance.

METHODS

This retrospective study was conducted at the Edendale Hospital located in a peri-urban area of KwaZulu-Natal. Children were included during their planned appointment. Drug resistance was assessed genotypically on proviral DNA.

RESULTS

From the 161 children included in this study, 93 samples were successfully genotyped. Both cohorts had comparable viral loads, but children treated early more often presented NRTI or NNRTI mutations, while there was no difference for PI mutations rates.

CONCLUSIONS

Treatment was highly effective when comparing virological outcomes in both early- and late-treated cohorts. The persistence of NNRTI mutations could lead to treatment failures in children older than 3 years initiating their therapy with a NNRTI, or for those switching from a PI to NNRTI based regimen. The accumulation of NRTI mutations may lead to a functional PI monotherapy and consequently to viral escape. To promote access to HIV genotyping in resource-limited settings is challenging but essential to avoid inappropriate therapy switches in case of virological failure, and to adapt national treatment guidelines in line with the epidemiology of resistance.

Escalating and sustained immunovirological dissociation among antiretroviral drug-experienced perinatally human immunodeficiency virus-1-infected children and adolescents living in the Central African Republic: A STROBE-compliant study

Sub-Saharan Africa has the vast majority (∼90%) of new pediatric acquired immunodeficiency syndrome cases worldwide. Biologically monitoring HIV-infected pediatric populations remains challenging. The differential interest of human immunodeficiency virus (HIV)-1 RNA loads and CD4 T-cell counts is debated for the treatment of pediatric acquired immunodeficiency syndrome patients.Long-term antiretroviral treatment (ART) outcomes regarding immunological and virological surrogate markers were longitudinally evaluated between 2009 and 2014 (over 57 months) in 245 perinatally HIV-1-infected children and adolescents born from HIV-infected mothers, treated at inclusion for at least 6 months by the World Health Organization-recommended ART in Bangui, Central African Republic.Patients were monitored over time biologically for CD4 T-cell counts, HIV-1 RNA loads, and drug resistance mutation genotyping.Children lost to follow-up totaled 6%. Four categories of immunovirological responses to ART were observed. At baseline, therapeutic success with sustained immunological and virological responses was observed in 80 (32.6%) children; immunological and virologic nonresponses occurred in 32 (13.0%) children; finally, the majority (133; 54.2%) of the remaining children showed discordant immunovirological responses. Among them, 33 (13.4%) children showed rapid virological responses to ART with an undetectable viral load, whereas immunological responses remained absent after 6 months of treatment and increased progressively over time in most of the cases, suggesting slow immunorestoration. Notably, nearly half of the children (40.8% at baseline and 48.2% at follow-up) harbored discordant immunovirological responses with a paradoxically high CD4 T-cell count and HIV-1 RNA load, which are always associated with high levels of drug resistance mutations. The latter category showed a significant increase over time, with a growth rate of 1.23% per year of follow-up.Our STROBE-compliant study demonstrates the high heterogeneity of biological responses under ART in children with frequent passage from 1 category to another over time. Close biological evaluation with access to routine plasma HIV-1 RNA load monitoring is crucial for adapting the complex outcomes of ART in HIV-infected children born from infected mothers.

Compromise of Second-Line Antiretroviral Therapy Due to High Rates of Human Immunodeficiency Virus Drug Resistance in Mozambican Treatment-Experienced Children With Virologic Failure

BACKGROUND

Virologic failure (VF) is highly prevalent in sub-Saharan African children on antiretroviral therapy (ART) and is often associated with human immunodeficiency virus drug resistance (DR). Most children still lack access to routine viral load (VL) monitoring for early identification of treatment failure, with implications for the efficacy of second-line ART.

METHODS

Children aged 1 to 14 years on ART for ≥12 months at 6 public facilities in Maputo, Mozambique were consecutively enrolled after informed consent. Chart review and caregiver interviews were conducted. VL testing was performed, and specimens with ≥1000 copies/mL were genotyped.

RESULTS

Of the 715 children included, the mean age was 103 months, 85.8% had no immunosuppression, 73.1% were taking stavudine/lamivudine/nevirapine, and 20.1% had a history prevention of mother-to-child transmission exposure. The mean time on ART was 60.0 months. VF was present in 259 patients (36.3%); 248 (95.8%) specimens were genotyped, and DR mutations were found in 238 (96.0%). Severe immunosuppression and nutritional decline were associated with DR. M184V and Y181C were the most common mutations. In the 238 patients with DR, standard second-line ART would have 0, 1, 2, and 3 effective antiretrovirals in 1 (0.4%), 74 (31.1%), 150 (63.0%), and 13 (5.5%) patients, respectively.

CONCLUSION

This cohort had high rates of VF and DR with frequent compromise of second-line ART. There is urgent need to scale-up VL monitoring and heat-stable protease inhibitor formulations or integrase inhibitorsfor a more a durable first-line regimen that can feasibly be implemented in developing settings.

Pooled nucleic acid testing strategy for monitoring HIV-1 treatment in resource limited settings

BACKGROUND

Virological monitoring (VM) and drug resistance (DR) analysis are crucial for effective HIV management. Due to the high cost of commercial assays, VM and DR analysis is not performed in resource-limited-settings.

OBJECTIVE

The objective of this study is to develop a pooling based algorithm for the combined identification of virologic treatment failure (VTF) by nucleic acid testing (NAT) and DR by sequencing - NAT+DR assay.

STUDY DESIGN

We enrolled 559 participants on first-line therapy and analyzed for VTF. The virologically suppressed participants were followed-up to see the VTF prevalence (>1000 copies/mL) and DR by the NAT+DR pooling. Each pool comprising 5 plasma samples were amplified by targeting reverse transcriptase gene, if found positive, the pool was deconvoluted and samples were individually tested for HIV RNA and DR. Assay characteristics of NAT+DR assay were calculated in comparison with commercial assay.

RESULTS

Of 559 participants, 67 had VTF at baseline and were excluded. Of the remaining 478 participants, 325 returned for follow-up and NAT+DR assay was performed for them. Of 65 pools tested, 13 pools were positive. On deconvolution 14 individuals were found to have VTF. Sensitivity, specificity, positive predictive value and negative predictive value was 100%, relative efficiency was 59% and 87% & 85% cost was saved for identifying VTF and combined identification of VTF and DR, respectively.

CONCLUSIONS

Pooled NAT+DR assay is likely a good strategy to drastically reduce the cost and sustainability of the VM and can thereby facilitate the scale-up of successful HIV treatment programs, and reduce unnecessary switching to second-line drugs in resource-limited-settings.

Financial Incentives to Increase Uptake of Pediatric HIV Testing (FIT): study protocol for a randomised controlled trial in Kenya

INTRODUCTION

Index case testing (ICT) to identify HIV-infected children is efficient but has suboptimal uptake. Financial incentives (FI) have overcome financial barriers in other populations by offsetting direct and indirect costs. A pilot study found FI to be feasible for motivating paediatric ICT among HIV-infected female caregivers. This randomised trial will determine the effectiveness of FI to increase uptake of paediatric ICT.

METHODS AND ANALYSIS

The Financial Incentives to Increase Uptake of Pediatric HIV Testing trial is a five-arm, unblinded, randomised controlled trial that determines whether FI increases timely uptake of paediatric ICT. The trial will be conducted in multiple public health facilities in western Kenya. Each HIV-infected adult enrolled in HIV care will be screened for eligibility: primary caregiver to one or more children of unknown HIV status aged 0-12 years. Eligible caregivers will be individually randomised at the time of recruitment in equal 1:1:1:1:1 allocation to one of five arms (US$0 (control), US$1.25, US$2.50, US$5.00 and US$10.00). The trial aims to randomise 800 caregivers. Incentives will be disbursed at the time of child HIV testing using mobile money transfer or cash. Arms will be compared in terms of the proportion of adults who complete testing for at least one child within 2 months of randomisation and time to testing. A cost-effectiveness analysis of FI for paediatric ICT will also be conducted.

ETHICS AND DISSEMINATION

This study was reviewed and approved by the University of Washington Institutional Review Board and the Kenyatta National Hospital Ethics and Research Committee. Trial results will be disseminated to healthcare workers at study sites, regional and national policymakers, and with patient populations at study sites (regardless of enrolment in the trial). Randomised trials of caregiver-child FI interventions pose unique study design, ethical and operational challenges, detailed here as a resource for future investigations.

TRIAL REGISTRATION NUMBER

NCT03049917; Pre-results.

Challenges to and opportunities for the adoption and routine use of early warning indicators to monitor pediatric HIV drug resistance in Kenya

Background

Pediatric non-adherence to antiretroviral therapy (ART), loss to follow-up, and HIV drug resistance (HIVDR) are challenges to achieving UNAIDS’ targets of 90% of those diagnosed HIV-positive receiving treatment, and 90% of those receiving treatment achieving viral suppression. In Kenya, the pediatric population represents 8% of total HIV infections and pediatric virological failure is estimated at 33%. The monitoring of early warning indicators (EWIs) for HIVDR can help to identify and correct gaps in ART program functioning to improve HIV care and treatment outcomes. However, EWIs have not been integrated into health systems. We assessed challenges to the use of EWIs and solutions to challenges identified by frontline health administrators.

Methods

We conducted key informant interviews with health administrators who were fully knowledgeable of the ART program at 23 pediatric ART sites in 18 counties across Kenya from May to June 2015. Thematic content analysis identified themes for three EWIs: on-time pill pick-up, retention in care, and virological suppression.

Results

Nine themes—six at the facility level and three at the patient level—emerged as major challenges to EWI monitoring. At the facility level, themes centered on system issues (e.g., slow return of viral load results), staff shortages and inadequate adherence counseling skills, lack of effective patient tracking and linkage systems, and lack of support for health personnel. At the patient level, themes focused on stigma, non-disclosure of HIV status to children who are age eligible, and little engagement of guardians in the children’s care.

Practical solutions identified included the use of lay health workers (e.g., peer educators, community health workers) to implement a variety of care and treatment tasks, whole facility approaches to adherence counseling, adolescent peer support groups, and working with children directly as soon as they are age eligible.

Discussion

The monitoring of EWIs has not been routine in health facilities in Kenya due to several challenges. However, facilities have implemented novel strategies to address some of these barriers. Future work is needed to assess whether scale-up of some of these approaches can aid in the effective use of EWIs and improving HIV care outcomes among the pediatric population.

Virological response and resistance among HIV-infected children receiving long-term antiretroviral therapy without virological monitoring in Uganda and Zimbabwe: Observational analyses within the randomised ARROW trial

BACKGROUND

Although WHO recommends viral load (VL) monitoring for those on antiretroviral therapy (ART), availability in low-income countries remains limited. We investigated long-term VL and resistance in HIV-infected children managed without real-time VL monitoring.

METHODS AND FINDINGS

In the ARROW factorial trial, 1,206 children initiating ART in Uganda and Zimbabwe between 15 March 2007 and 18 November 2008, aged a median 6 years old, with median CD4% of 12%, were randomised to monitoring with or without 12-weekly CD4 counts and to receive 2 nucleoside reverse transcriptase inhibitors (2NRTI, mainly abacavir+lamivudine) with a non-nucleoside reverse transcriptase inhibitor (NNRTI) or 3 NRTIs as long-term ART. All children had VL assayed retrospectively after a median of 4 years on ART; those with >1,000 copies/ml were genotyped. Three hundred and sixteen children had VL and genotypes assayed longitudinally (at least every 24 weeks). Overall, 67 (6%) switched to second-line ART and 54 (4%) died. In children randomised to WHO-recommended 2NRTI+NNRTI long-term ART, 308/378 (81%) monitored with CD4 counts versus 297/375 (79%) without had VL <1,000 copies/ml at 4 years (difference = +2.3% [95% CI -3.4% to +8.0%]; P = 0.43), with no evidence of differences in intermediate/high-level resistance to 11 drugs. Among children with longitudinal VLs, only 5% of child-time post-week 24 was spent with persistent low-level viraemia (80-5,000 copies/ml) and 10% with VL rebound ≥5,000 copies/ml. No child resuppressed <80 copies/ml after confirmed VL rebound ≥5,000 copies/ml. A median of 1.0 (IQR 0.0,1.5) additional NRTI mutation accumulated over 2 years' rebound. Nineteen out of 48 (40%) VLs 1,000-5,000 copies/ml were immediately followed by resuppression <1,000 copies/ml, but only 17/155 (11%) VLs ≥5,000 copies/ml resuppressed (P < 0.0001). Main study limitations are that analyses were exploratory and treatment initiation used 2006 criteria, without pre-ART genotypes.

CONCLUSIONS

In this study, children receiving first-line ART in sub-Saharan Africa without real-time VL monitoring had good virological and resistance outcomes over 4 years, regardless of CD4 monitoring strategy. Many children with detectable low-level viraemia spontaneously resuppressed, highlighting the importance of confirming virological failure before switching to second-line therapy. Children experiencing rebound ≥5,000 copies/ml were much less likely to resuppress, but NRTI resistance increased only slowly. These results are relevant to the increasing numbers of HIV-infected children receiving first-line ART in sub-Saharan Africa with limited access to virological monitoring.

TRIAL REGISTRATION

ISRCTN Registry, ISRCTN24791884.

Predictors of Virologic Failure on First-line Antiretroviral Therapy Among Children in a Referral Pediatric Center in Cameroon

BACKGROUND

Suboptimal response to antiretroviral therapy (ART) is common among children living with HIV (CLHIV) in resource-limited settings. We sought to assess virologic failure (VF), time for switching to second-line regimens and factors associated with VF in CLHIV receiving first-line ART in Cameroon.

METHODS

An observational cohort study was conducted in 375 CLHIV initiating a first-line ART and treated for ≥6 months at the National Social Insurance Fund Hospital in Yaoundé-Cameroon from 2009 to 2013. Using logistic regression, predictors of VF and delayed switch were assessed by univariate and multivariate analysis. P < 0.05 was considered statistically significant.

RESULTS

Overall, 17% (64/375) CLHIV experienced VF on first-line ART after a median time of 28 (interquartile range: 22-38) months. After VF, median time to switching from first- to second-line ART was 20 (interquartile range: 8-24) months. In multivariate analysis, VF was associated with male gender (adjusted odds ratio: 0.36; 95% confidence interval: 0.19-0.71; P = 0.003), motherless children (adjusted odds ratio: 2.9; 95% confidence interval: 1.3-6.06; P = 0.005) and treatment with stavudine-containing compared with zidovudine-containing regimens (P = 0.022). Overall, male gender, orphanhood (motherless) and treatment with stavudine-containing regimens predicted VF at a rate of 70% (area under curve =0.70).

CONCLUSION

VF on first-line pediatric ART is common, and switching children failing first-line to second-line ART is considerably delayed. These results suggest performance of pediatric ART program can be improved by targeting orphans, adapting counseling for male children, complete phasing-out of stavudine and ensuring timely switch to second-line regimens.

HIV drug resistance in infants increases with changing prevention of mother-to-child transmission regimens

OBJECTIVES

The objectives of this study were to determine HIV drug resistance (HIVDR) prevalence in Zambian infants upon diagnosis, and to determine how changing prevention of mother-to-child transmission (PMTCT) drug regimens affect drug resistance.

DESIGN

Dried blood spot (DBS) samples from infants in the Lusaka District of Zambia, obtained during routine diagnostic screening, were collected during four different years representing three different PMTCT drug treatment regimens.

METHODS

DNA extracted from dried blood spot samples was used to sequence a 1493 bp region of the reverse transcriptase gene. Sequences were analyzed via the Stanford HIVDRdatabase (http://hivdb.standford.edu) to screen for resistance mutations.

RESULTS

HIVDR in infants increased from 21.5 in 2007/2009 to 40.2% in 2014. Nonnucleoside reverse transcriptase inhibitor resistance increased steadily over the sampling period, whereas nucleoside reverse transcriptase inhibitor resistance and dual class resistance both increased more than threefold in 2014. Analysis of drug resistance scores in each group revealed increasing strength of resistance over time. In 2014, children with reported PMTCT exposure, defined as infant prophylaxis and/or maternal treatment, showed a higher prevalence and strength of resistance compared to those with no reported exposure.

CONCLUSION

HIVDR is on the rise in Zambia and presents a serious problem for the successful lifelong treatment of HIV-infected children. PMTCT affects both the prevalence and strength of resistance and further research is needed to determine how to mitigate its role leading to resistance.

High Prevalence of Abacavir-associated L74V/I Mutations in Kenyan Children Failing Antiretroviral Therapy

A survey of 461 HIV-infected Kenyan children receiving antiretroviral therapy found 143 (31%) failing virologically. Drug resistance mutations were found in 121; 37 had L74V/I mutations, with 95% receiving abacavir (ABC)-containing regimens. L74V/I was associated with current ABC usage (P = 0.0001). L74V/I may be more prevalent than previously realized in children failing ABC-containing regimens, even when time on treatment has been short. Ongoing rigorous pediatric drug resistance surveillance is needed.

Second-line HIV Treatment in Ugandan Children: Favorable Outcomes and No Protease Inhibitor Resistance

BACKGROUND

Data on pediatric second-line antiretroviral treatment (ART) outcomes are scarce, but essential to evaluate second-line and design third-line regimens.

METHODS

Children ≤12 years switching to second-line ART containing a protease inhibitor (PI) in Uganda were followed for 24 months. Viral load (VL) was determined at switch to second-line and every 6 months thereafter; genotypic resistance testing was done if VL ≥ 1000 cps/ml.

RESULTS

60 children were included in the analysis; all had ≥1 drug resistance mutations at switch. Twelve children (20.0%) experienced treatment failure; no PI mutations were detected. Sub-optimal adherence and underweight were associated with treatment failure.

CONCLUSIONS

No PI mutations occurred in children failing second-line ART, which is reassuring as pediatric third-line is not routinely available in these settings. Poor adherence rather than HIV drug resistance is likely to be the main mechanism for treatment failure and should receive close attention in children on second-line ART.

High levels of virological failure with major genotypic resistance mutations in HIV-1-infected children after 5 years of care according to WHO-recommended 1st-line and 2nd-line antiretroviral regimens in the Central African Republic: A cross-sectional study

A large cohort of 220 HIV-1-infected children (median [range] age: 12 [4-17] years) was cared and followed up in the Central African Republic, including 198 in 1st-line and 22 in 2nd-line antiretroviral regimens. Patients were monitored clinically and biologically for HIV-1 RNA load and drug resistance mutations (DRMs) genotyping. A total of 87 (40%) study children were virological responders and 133 (60%) nonresponders. In children with detectable viral load, the majority (129; 97%) represented a virological failure. In children receiving 1st-line regimens in virological failure for whom genotypic resistance test was available, 45% displayed viruses harboring at least 1 DRM to NNRTI or NRTI, and 26% showed at least 1 major DRM to NNRTI or NRTI; more than half of children in 1st-line regimens were resistant to 1st-generation NNRTI and 24% of the children in 1st-line regimens had a major DRMs to PI. Virological failure and selection of DRMs were both associated with poor adherence. These observations demonstrate high rate of virological failure after 3 to 5 years of 1st-line or 2nd-line antiretroviral treatment, which is generally associated with DRMs and therapeutic failure. Overall, more than half (55%) of children receiving 1st-line antiretroviral treatment for a median of 3.4 years showed virological failure and antiretroviral-resistance and thus eligible to 2nd-line treatment. Furthermore, two-third (64%) of children under 2nd-line therapy were eligible to 3rd-line regimen. Taken together, these observations point the necessity to monitor antiretroviral-treated children by plasma HIV-1 RNA load to diagnose as early as possible the therapeutic failure and operate switch to a new therapeutic line.

Development of HIV drug resistance and therapeutic failure in children and adolescents in rural Tanzania: an emerging public health concern

Objective:

To investigate the prevalence and determinants of virologic failure and acquired drug resistance-associated mutations (DRMs) in HIV-infected children and adolescents in rural Tanzania.

Design:

Prospective cohort study with cross-sectional analysis.

Methods:

All children 18 years or less attending the paediatric HIV Clinic of Ifakara and on antiretroviral therapy (ART) for at least 12 months were enrolled. Participants with virologic failure were tested for HIV-DRM. Pre-ART samples were used to discriminate acquired and transmitted resistances. Multivariate logistic regression analysis identified factors associated with virologic failure and the acquisition of HIV-DRM.

Results:

Among 213 children on ART for a median of 4.3 years, 25.4% failed virologically. ART-associated DRM were identified in 90%, with multiclass resistances in 79%. Pre-ART data suggested that more than 85% had acquired key mutations during treatment. Suboptimal adherence [odds ratio (OR) = 3.90; 95% confidence interval (CI) 1.11–13.68], female sex (aOR = 2.57; 95% CI 1.03–6.45), and current nonnucleoside reverse transcriptase inhibitor-based ART (aOR = 7.32; 95% CI 1.51–35.46 compared with protease inhibitor-based) independently increased the odds of virologic failure. CD4⁺ T-cell percentage (aOR = 0.20; 0.10–0.40 per additional 10%) and older age at ART initiation (aOR = 0.84 per additional year of age; 95% CI 0.73–0.97) were protective (also in predicting acquired HIV-DRM). At the time of virologic failure, less than 5% of the children fulfilled the WHO criteria for immunologic failure.

Conclusion:

Virologic failure rates in children and adolescents were high, with the majority of ART-failing children harbouring HIV-DRM. The WHO criteria for immunologic treatment failure yielded an unacceptably low sensitivity. Viral load monitoring is urgently needed to maintain future treatment options for the millions of African children living with HIV.

In-depth analysis of HIV-1 drug resistance mutations in HIV-infected individuals failing first-line regimens in West and Central Africa

OBJECTIVE

In resource-limited countries, antiretroviral therapy (ART) has been scaled up, but individual monitoring is still suboptimal. Here, we studied whether or not ART had an impact on the frequency and selection of drug resistance mutations (DRMs) under these settings. We also examined whether differences exist between HIV-1 genetic variants.

DESIGN

A total of 3736 sequences from individuals failing standard first-line ART (n = 1599, zidovudine/stavudine + lamivudine + neviparine/efavirenz) were analyzed and compared with sequences from reverse transcriptase inhibitor (RTI)-naive individuals (n = 2137) from 10 West and Central African countries.

METHODS

Fisher exact tests and corrections for multiple comparisons were used to assess the significance of associations.

RESULTS

All RTI-DRM from the 2015 International Antiviral Society list, except F227C, and nine mutations from other expert lists were observed to confer extensive resistance and cross-resistance. Five additional independently selected mutations (I94L, L109I, V111L, T139R and T165L) were statistically associated with treatment. The proportion of sequences with multiple mutations and the frequency of all thymidine analog mutations, M184V, certain NNRTIS, I94L and L109I showed substantial increase with time on ART. Only one nucleoside and two nonnucleoside RTI-DRMs differed by subtype/circulating recombinant form.

CONCLUSION

This study validates the global robustness of the actual DRM repertoire, in particular for circulating recombinant form 02 predominating in West and Central Africa, despite our finding of five additional selected mutations. However, long-term ART without virological monitoring clearly leads to the accumulation of mutations and the emergence of additional variations, which limit drug options for treatment and can be transmitted. Improved monitoring and optimization of ART are necessary for the long-term effectiveness of ART.

Affordable HIV drug-resistance testing for monitoring of antiretroviral therapy in sub-Saharan Africa

Increased provision of antiretroviral therapy in sub-Saharan Africa has led to a growing number of patients with therapy failure and acquired drug-resistant HIV, driving the demand for more costly further lines of antiretroviral therapy. In conjunction with accelerated access to viral load monitoring, feasible and affordable technologies to detect drug-resistant HIV could help maximise the durability and rational use of available drug regimens. Potential low-cost technologies include in-house Sanger and next-generation sequencing in centralised laboratories, and point mutation assays and genotype-free systems that predict response to antiretroviral therapy at point-of-care. Strengthening of centralised high-throughput laboratories, including efficient systems for sample referral and results delivery, will increase economies-of-scale while reducing costs. Access barriers can be mitigated by standardisation of in-house assays into commercial kits, use of polyvalent instruments, and adopting price-reducing strategies. A stepwise rollout approach should improve feasibility, prioritising WHO-recommended population-based surveillance and management of complex patient categories, such as patients failing protease inhibitor-based antiretroviral therapy. Implementation research, adaptations of existing WHO guidance, and political commitment, will be key to support the appropriate investments and policy changes. In this Personal View, we discuss the potential role of HIV drug resistance testing for population-based surveillance and individual patient management in sub-Saharan Africa. We review the strengths and challenges of promising low-cost technologies and how they can be implemented.

Outcomes after viral load rebound on first-line antiretroviraltreatment in children with HIV in the UK and Ireland: an observational cohort study

BACKGROUND

About a third of children with HIV have virological failure within 2 years of beginning antiretroviral treatment (ART). We assessed the probability of switch to second-line ART or virological re-suppression without switch in children who had virological rebound on first-line ART in the UK and Ireland.

METHODS

In this study, we used data reported to the Collaborative HIV Paediatric Study (CHIPS), a national multicentre observational cohort. We included children with virological rebound (confirmed viral load>400 copies per mL after suppression<400 copies per mL) on first-line ART. We did a competing-risk analysis to estimate the probability of switch to second-line treatment, confirmed resuppression (two consecutive viral load measurments<400 copies per mL) without switch, and continued viral load above 400 copies per mL without switch. We also assessed factors that predicted a faster time to switch.

FINDINGS

Of the 900 children starting first-line ART who had a viral load below 400 copies per mL within a year of starting treatment, 170 (19%) had virological rebound by a median of 20·6 months (IQR 9·7–40·5). At rebound, median age was 10·6 years (5·6–13·4), median viral load was 3·6 log10 copies per mL (3·1–4·2), and median CD4% was 24% (17–32). 89 patients (52%) switched to second-line ART at a median of 4·9 months (1·7–13·4) after virological rebound, 53 (31%) resuppressed without switch (19 [61%] of 31 patients on a first-line regimen that included a protease inhibitor and 31 [24%] of 127 patients on a first-line regimen that included a non-nucleoside reverse transcriptase inhibitor; NNRTI), and 28 (16%) neither resuppressed nor switched. At 12 months after rebound, the estimated probability of switch was 38% (95% CI 30–45) and of resuppression was 27% (21–34). Faster time to switch was associated with a higher viral load (p<0·0001), later calendar year at virological rebound (p=0·02), and being on an NNRTI-based or triple nucleoside reverse transcriptase inhibitor-based versus protease-inhibitor-based first-line regimen (p=0·001).

INTERPRETATION

A third of children with virological rebound resuppressed without switch. Clinicians should consider the possibility of resuppression with adherence support before switching treatment in children with HIV.

FUNDING

NHS England (London Specialised Commissioning Group).

A Case Series of Acquired Drug Resistance-Associated Mutations in Human Immunodeficiency Virus-Infected Children: An Emerging Public Health Concern in Rural Africa

The acquisition of drug-resistance mutations among African children living with in human immunodeficiency virus on antiretroviral treatment has been scarcely reported. This threatens the overall success of antiretroviral programs and the clinical outcomes of children in care. We present a well characterized series of children from rural Tanzania with acquired drug-resistance mutations to contribute to the better understanding of this emerging public health concern.

HIV-1 protease inhibitor drug resistance in Kenyan antiretroviral treatment-naive and -experienced injection drug users and non-drug users

BACKGROUND

Although injection drug use drives antiretroviral drug resistance, the prevalence of protease inhibitor (PI) resistance among Kenyan IDUs remains undetermined. We, therefore, explored PI resistance mutations and their association with viral load and CD4+ T cell counts in HIV-1 infected IDUs (ART-naive, n = 32; and -experienced, n = 47) and non-drug users (ART-naive, n = 21; and -experienced, n = 32) naive for PI treatment from coastal Kenya.

RESULTS

Only IDUs harboured major PI resistance mutations consisting of L90M, M46I and D30 N among 3 (6.4 %) ART-experienced and 1 (3.1 %) -naive individuals. Minor PI mutations including A71T, G48E, G48R, I13V, K20I, K20R, L10I, L10V, L33F, L63P, T74S, V11I, and V32L were detected among the ART-experienced (36.2 vs. 46.9 %) and -naive (43.8 vs. 66.7 %) IDUs and non-drug users, respectively. All the four IDUs possessing major mutations had high viral load while three presented with CD4+ T cell counts of <500 cells/ml. Among the ART-naive non-drug users, CD4+ T cell counts were significantly lower in carriers of minor mutations compared to non-carriers (P < 0.05).

CONCLUSION

Transmitted drug resistance may occur in IDUs underscoring the need for genotyping resistance before initiating PI treatment.

Tackling virological failure in HIV-infected children living in Africa

Drug resistance in HIV-infected children is one of the main contributors to antiretroviral treatment (ART) failure, especially in developing countries. Sub-Saharan Africa has the largest burden of pediatric HIV infection in the world. Herein, we systematically review the current status of ART failure in HIV-infected African children. A literature search for publications within 10 years was performed through PubMed to identify relevant articles. Included studies examined the impact of timing of ART initiation, criteria for diagnosing therapeutic failure, predictors of therapeutic failure, management strategies and future directions to minimize failure rates in these pediatric populations. Although there is scale-up of ART programs in Africa, novel therapeutic and management strategies are needed to overcome current challenges.

Paediatric European Network for Treatment of AIDS (PENTA) guidelines for treatment of paediatric HIV-1 infection 2015: optimizing health in preparation for adult life

The 2015 Paediatric European Network for Treatment of AIDS (PENTA) guidelines provide practical recommendations on the management of HIV‐1 infection in children in Europe and are an update to those published in 2009. Aims of treatment have progressed significantly over the last decade, moving far beyond limitation of short‐term morbidity and mortality to optimizing health status for adult life and minimizing the impact of chronic HIV infection on immune system development and health in general. Additionally, there is a greater need for increased awareness and minimization of long‐term drug toxicity. The main updates to the previous guidelines include: an increase in the number of indications for antiretroviral therapy (ART) at all ages (higher CD4 thresholds for consideration of ART initiation and additional clinical indications), revised guidance on first‐ and second‐line ART recommendations, including more recently available drug classes, expanded guidance on management of coinfections (including tuberculosis, hepatitis B and hepatitis C) and additional emphasis on the needs of adolescents as they approach transition to adult services. There is a new section on the current ART ‘pipeline’ of drug development, a comprehensive summary table of currently recommended ART with dosing recommendations. Differences between PENTA and current US and World Health Organization guidelines are highlighted and explained.

HIV diversity and drug resistance from plasma and non-plasma analytes in a large treatment programme in western Kenya

INTRODUCTION

Antiretroviral resistance leads to treatment failure and resistance transmission. Resistance data in western Kenya are limited. Collection of non-plasma analytes may provide additional resistance information.

METHODS

We assessed HIV diversity using the REGA tool, transmitted resistance by the WHO mutation list and acquired resistance upon first-line failure by the IAS-USA mutation list, at the Academic Model Providing Access to Healthcare (AMPATH), a major treatment programme in western Kenya. Plasma and four non-plasma analytes, dried blood-spots (DBS), dried plasma-spots (DPS), ViveST(TM)-plasma (STP) and ViveST-blood (STB), were compared to identify diversity and evaluate sequence concordance.

RESULTS

Among 122 patients, 62 were treatment-naïve and 60 treatment-experienced; 61% were female, median age 35 years, median CD4 182 cells/µL, median viral-load 4.6 log10 copies/mL. One hundred and ninety-six sequences were available for 107/122 (88%) patients, 58/62 (94%) treatment-naïve and 49/60 (82%) treated; 100/122 (82%) plasma, 37/78 (47%) attempted DBS, 16/45 (36%) attempted DPS, 14/44 (32%) attempted STP from fresh plasma and 23/34 (68%) from frozen plasma, and 5/42 (12%) attempted STB. Plasma and DBS genotyping success increased at higher VL and shorter shipment-to-genotyping time. Main subtypes were A (62%), D (15%) and C (6%). Transmitted resistance was found in 1.8% of plasma sequences, and 7% combining analytes. Plasma resistance mutations were identified in 91% of treated patients, 76% NRTI, 91% NNRTI; 76% dual-class; 60% with intermediate-high predicted resistance to future treatment options; with novel mutation co-occurrence patterns. Nearly 88% of plasma mutations were identified in DBS, 89% in DPS and 94% in STP. Of 23 discordant mutations, 92% in plasma and 60% in non-plasma analytes were mixtures. Mean whole-sequence discordance from frozen plasma reference was 1.1% for plasma-DBS, 1.2% plasma-DPS, 2.0% plasma-STP and 2.3% plasma-STB. Of 23 plasma-STP discordances, one mutation was identified in plasma and 22 in STP (p<0.05). Discordance was inversely significantly related to VL for DBS.

CONCLUSIONS

In a large treatment programme in western Kenya, we report high HIV-1 subtype diversity; low plasma transmitted resistance, increasing when multiple analytes were combined; and high-acquired resistance with unique mutation patterns. Resistance surveillance may be augmented by using non-plasma analytes for lower-cost genotyping in resource-limited settings.

Drug resistance in the HIV-1-infected paediatric population worldwide: a systematic review

BACKGROUND

Drug resistance monitoring of the paediatric HIV-1-infected population is required to optimize treatment success and preserve future treatment options.

OBJECTIVES

To explore the current knowledge of HIV drug resistance (HIVDR) in naive and pretreated HIV-1-infected paediatric populations across diverse settings and sampling time periods.

METHODS

PubMed database screened until May 2013. We selected publications including data on transmitted (TDR) and acquired drug resistance mutation (DRM) rates and/or pol sequences for HIVDR testing in paediatric patients. We recorded the children's country, age, study period, number of children with pol sequences, presence or absence of antiretroviral treatment (ART) at sampling time, viral region sequenced, HIVDR rate to the three main drug classes (single, double or triple), the considered resistance mutation list and performed assay, specimen type, HIV-1 variants and subtyping methodology when available.

RESULTS

Forty-one selected studies showed HIVDR data from 2538 paediatric HIV-1-infected patients (558 naive and 1980 pretreated) from 30 countries in Africa (11), Asia (6), America (10) and Europe (3). Both TDR and DRM prevalence were reported in 9 studies, only TDR in 6 and only DRM in 26. HIVDR prevalence varied across countries and periods. Most studies used in-house resistance assays using plasma or infected cells. HIV-1 non-B variants were prevalent in 18 paediatric cohorts of the 24 countries with reported subtypes. Only five countries (Uganda, Spain, the UK, Brazil and Thailand) presented resistance data in ≥200 patients.

CONCLUSIONS

Systematic and periodic studies among infected children are crucial to design a more suitable first- or second-line therapy.

Antiretroviral treatment, management challenges and outcomes in perinatally HIV-infected adolescents

Three decades into the HIV/AIDS epidemic there is a growing cohort of perinatally HIV-infected adolescents globally. Their survival into adolescence and beyond represent one of the major successes in the battle against the disease that has claimed the lives of millions of children. This population is diverse and there are unique issues related to antiretroviral treatment and management. Drawing from the literature and experience, this paper discusses several broad areas related to antiretroviral management, including: 1) diverse presentation of HIV, (2) use of combination antiretroviral therapy including in the setting of co-morbidities and rapid growth and development, (3) challenges of cART, including nonadherence, resistance, and management of the highly treatment-experienced adolescent patient, (4) additional unique concerns and management issues related to PHIV-infected adolescents, including the consequences of longterm inflammation, risk of transmission, and transitions to adult care. In each section, the experience in both resource-rich and limited settings are discussed with the aim of highlighting the differences and importantly the similarities, to share lessons learnt and provide insight into the multi-faceted approaches that may be needed to address the challenges faced by this unique and resilient population.