Drug resistance is widespread among children who receive long-term antiretroviral treatment at a rural Tanzanian hospital

Pharmacokinetics, Tolerability, and Safety of Doravirine and Doravirine/Lamivudine/Tenofovir Disoproxil Fumarate Fixed-Dose Combination Tablets in Adolescents Living With HIV: Week 24 Results From IMPAACT 2014

BACKGROUND

We studied the pharmacokinetics (PK) and safety of 100-mg doravirine and doravirine/lamivudine/tenofovir disoproxil fumarate fixed-dose combination (100/300/300 mg DOR FDC) treatment in adolescents with HIV-1.

METHODS

Adolescents ages 12 to younger than 18 years were enrolled in 2 sequential cohorts. Cohort 1 evaluated intensive PK and short-term safety of 100-mg single-dose doravirine in adolescents ≥35 kg. Cohort 2 participants either initiated treatment with DOR FDC (antiretroviral (ARV)-naïve) or switched to DOR FDC from a previous ARV regimen (virologically suppressed). The first 10 Cohort 2 participants had intensive PK evaluations, and safety, sparse PK, and HIV RNA were assessed through week 24.

RESULTS

Fifty-five adolescents, median age 15.0 years and baseline weight 51.5 kg, were enrolled. Nine participants completed Cohort 1 PK assessments (8 of the 9 participants weighed ≥45 kg) and 45 initiated study drug in Cohort 2. The doravirine geometric mean (GM) AUC 0-∞ was 34.8 μM∙hour, and the GM C 24 was 514 nM after a single dose, with a predicted steady-state GM C 24,ss,pred of 690 nM. Cohort 2 enrolled adolescents weighing ≥45 kg. Plasma concentrations of doravirine, tenofovir, and lamivudine achieved by Cohort 2 participants were similar to those reported in adults. No drug-related serious or grade 3 or 4 adverse events occurred. Forty-two of 45 participants (93.3%; 95% CI: [81.7, 98.6]) achieved or maintained HIV-1 RNA <40 copies/mL.

CONCLUSIONS

Doravirine and DOR FDC achieved target PK in adolescents with HIV-1. DOR FDC was well-tolerated and maintained excellent virologic efficacy through 24 weeks, offering a favorable option for adolescents.

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.

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 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.

High rates of virological failure and drug resistance in perinatally HIV-1-infected children and adolescents receiving lifelong antiretroviral therapy in routine clinics in Togo

INTRODUCTION

Antiretroviral treatment (ART) has been scaled up over the last decade but compared to adults, children living with HIV are less likely to receive ART. Moreover, children and adolescents are more vulnerable than adults to virological failure (VF) and emergence of drug resistance. In this study we determined virological outcome in perinatally HIV-1-infected children and adolescents receiving ART in Togo.

METHODS

HIV viral load (VL) testing was consecutively proposed to all children and adolescents who were on ART for at least 12 months when attending HIV healthcare services for their routine follow-up visit (June to September 2014). Plasma HIV-1 VL was measured using the m2000 RealTime HIV-1 assay (Abbott Molecular, Des Plaines, IL, USA). Genotypic drug resistance was done for all samples with VL>1000 copies/ml.

RESULTS AND DISCUSSION

Among 283 perinatally HIV-1-infected children and adolescents included, 167 (59%) were adolescents and 116 (41%) were children. The median duration on ART was 48 months (interquartile range: 28 to 68 months). For 228 (80.6%), the current ART combination consisted of two nucleoside reverse transcriptase inhibitors (NRTIs) (zidovudine and lamivudine) and one non-nucleoside reverse transcriptase inhibitor (NNRTI) (nevirapine or efavirenz). Only 28 (9.9%) were on a protease inhibitor (PI)-based regimen. VL was below the detection limit (i.e. 40 copies/ml) for 102 (36%), between 40 and 1000 copies/ml for 35 (12.4%) and above 1000 copies/ml for 146 (51.6%). Genotypic drug-resistance testing was successful for 125/146 (85.6%); 110/125 (88.0%) were resistant to both NRTIs and NNRTIs, 1/125 (0.8%) to NRTIs only, 4/125 (3.2%) to NNRTIs only and three harboured viruses resistant to reverse transcriptase and PIs. Overall, 86% (108/125) of children and adolescents experiencing VF and successfully genotyped, corresponding thus to at least 38% of the study population, had either no effective ART or had only a single effective drug in their current ART regimen.

CONCLUSIONS

Our study provided important information on virological outcome on lifelong ART in perinatally HIV-1-infected children and adolescents who were still on ART and continued to attend antiretroviral (ARV) clinics for follow-up visits. Actual conditions for scaling up and monitoring lifelong ART in children in resource-limited countries can have dramatic long-term outcomes and illustrate that paediatric ART receives inadequate attention.

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.

Frequent detection of antiretroviral drug resistance in HIV-1-infected orphaned children followed at a donor-funded rural pediatric clinic in Dodoma, Tanzania

A total of 81 HIV-1 protease (PR) and reverse transcriptase (RT) sequences were obtained from 46 drug-naive and 35 pretreated individual HIV-1-infected orphaned children followed at a donor-funded rural pediatric clinic in Dodoma, Tanzania. PR and RT sequencing was performed by home-brew technology on 70 plasma samples and 11 dried blood spot specimens. Nucleoside RT inhibitor (NRTI) resistance mutations were detected in 2.2% of drug-naive and 82.9% of pretreated children. Nonnucleoside RT inhibitor (NNRTI) resistance mutations were detected in 69.6% of drug-naive and 91.4% of pretreated children. Resistance to protease inhibitors was rare (8.6% in pretreated children). Based on few complete treatment records, only around 20% of the treated children had undetectable plasma HIV-1 RNA. The rate of NRTI and NNRTI resistance in this donor-funded rural pediatric clinic was high and appeared to limit virological response to treatment.

Durability of antiretroviral therapy and predictors of virologic failure among perinatally HIV-infected children in Tanzania: a four-year follow-up

BACKGROUND

In Tanzania, HIV-1 RNA testing is rarely available and not standard of care. Determining virologic failure is challenging and resistance mutations accumulate, thereby compromising second-line therapy. We evaluated durability of antiretroviral therapy (ART) and predictors of virologic failure among a pediatric cohort at four-year follow-up.

METHODS

This was a prospective cross-sectional study with retrospective chart review evaluating a perinatally HIV-infected Tanzanian cohort enrolled in 2008-09 with repeat HIV-1 RNA in 2012-13. Demographic, clinical, and laboratory data were extracted from charts, resistance mutations from 2008-9 were analyzed, and prospective HIV RNA was obtained.

RESULTS

161 (78%) participants of the original cohort consented to repeat HIV RNA. The average age was 12.2 years (55% adolescents ≥12 years). Average time on ART was 6.4 years with 41% receiving second-line (protease inhibitor based) therapy. Among those originally suppressed on a first-line (non-nucleoside reverse transcriptase based regimen) 76% remained suppressed. Of those originally failing first-line, 88% were switched to second-line and 72% have suppressed virus. Increased level of viremia and duration of ART trended with an increased number of thymidine analogue mutations (TAMs). Increased TAMs increased the odds of virologic failure (p = 0.18), as did adolescent age (p < 0.01).

CONCLUSIONS

After viral load testing in 2008-09 many participants switched to second-line therapy. The majority achieved virologic suppression despite multiple resistance mutations. Though virologic testing would likely hasten the switch to second-line among those failing, methods to improve adherence is critical to maximize durability of ART and improve virologic outcomes among youth in resource-limited settings.

Antiretroviral treatment failure predicts mortality in rural Tanzania

Virological monitoring of HIV-infected patients on antiretroviral treatment (ART) is rarely available in resource-limited settings and many patients experience unrecognized virological failure. We studied the long-term consequences of virological failure in rural Tanzania. Previously, virological efficacy was measured in a cohort treated with ART. In the present study, patients with virological failure (VF; HIV-RNA >400 copies/ml) were followed up and compared to those with virological response (VR; HIV-RNA <400 copies/ml) with regard to mortality, CD4 change and subsequent virological outcome. Fifty-six patients with VF had a median CD4 count of 358 cells/µl (interquartile range [IQR] 223-635) and a median HIV-RNA of 13,573 copies/ml (IQR 2326-129,736). Median CD4 count for those with VR was 499 cells/µl (IQR 290-636). During a median follow-up time of 39 months (IQR 18-42), 8 of 56 patients (14.3%) with VF died, compared to 1 of 63 patients (1.6%) with VR (p = 0.009). All registered deaths were HIV-related. Of 55 patients with subsequent HIV-RNA measurements, only 12 of 30 (40%) patients with VF achieved virological suppression, compared to 20 of 25 (80%) patients with VR (p = 0.003). Virological failure predicted death and subsequent virological failure in patients on ART in a resource-limited setting.

HIV-1 drug mutations in children from northern Tanzania

OBJECTIVES

In resource-limited settings, it is a challenge to get quality clinical specimens due to poor infrastructure for their collection, transportation, processing and storage. Using dried blood spots (DBS) might be an alternative to plasma for HIV-1 drug resistance testing in this setting. The objectives of this study were to determine mutations associated with antiretroviral resistance among children <18 months old born to HIV-1-infected mothers enrolled in prevention of mother-to-child transmission services in northern Tanzania.

PATIENTS AND METHODS

Kilimanjaro Christian Medical Center (KCMC) Clinical Laboratory is the zonal centre for early infant diagnosis using DBS in northern Tanzania. DBS were collected from January 2011 to December 2012. Mothers were kept on triple therapy and single-dose nevirapine before pregnancy and during labour, respectively. Infants were given single-dose nevirapine and most of them were breastfed. Genotypic resistance was determined in those with a viral load of >400 copies/mL.

RESULTS

Genotypic resistance mutations were detected in 13 of 46 children (28%). HIV-1 genotypes were A1 (n = 27), C (n = 10), A/D (n = 4), D (n = 3) and CRF10_CD (n = 2). The median age was 12 weeks (IQR 6-28). The mean log10 viral load was 3.87 copies/mL (SD 0.995). All major mutations were detected in the reverse transcriptase gene and none in the protease gene region. The most frequent mutations were Y181C (n = 8) and K103N (n = 4), conferring resistance to non-nucleoside reverse transcriptase inhibitors.

CONCLUSIONS

One-third of infants newly diagnosed with HIV in northern Tanzania harboured major drug resistance mutations to currently used antiretroviral regimens. These mutations were detected from DBS collected from the field and stored at room temperature. Surveillance of drug resistance among this population in resource-limited settings is warranted.

Long-term effectiveness of combination antiretroviral therapy and prevalence of HIV drug resistance in HIV-1-infected children and adolescents in Rwanda

OBJECTIVE

To determine the long-term outcomes of treatment and prevalence of genotypic drug resistance in children and adolescents on combination antiretroviral therapy.

METHODS

A cross-sectional study (September 2009 to October 2010) in which clinical, immunologic and virologic outcomes were assessed at a single-study visit and through patient records in a cohort of HIV-infected children and adolescents. Risk factors for clinical and immunologic responses and virologic outcome were evaluated using logistic regression, and the accuracy of clinical and immunologic criteria in identifying virologic failure was assessed.

RESULTS

Four hundred twenty-four patients were enrolled with a median age of 10.8 years (range: 1.7-18.8) and a median duration on combination antiretroviral therapy of 3.4 years (range: 1.0-8.1). Thirty-three percent were stunted and 17% underweight. Eighty-four percent (95% confidence interval: 79-87) of children >5 years had CD4 ≥350 cells/mm and in 74% (95% confidence interval: 62-84) of younger children CD4% was ≥25. CD4 values and age at combination antiretroviral therapy initiation were independently associated with CD4 outcomes; 124 (29%) had HIV-1 RNA ≥1000 copies/mL, with no significant predictors. Sensitivity for weight-for-age and height-for-age and CD4 cells (<350/mm) remained under 50% (15-42%); CD4 cells showed the best specificity, ranging from 91% to 97%. Of 52 samples tested, ≥1 mutations were observed in 91% (nucleoside reverse transcriptase inhibitors) and 95% (non-nucleoside reverse transcriptase inhibitors); 1 to 2 thymidine analogue-associated mutations were detected in 16 (31%) and ≥3 thymidine analogue-associated mutations in 7 (13%).

CONCLUSION

Nearly 1 in 3 children showed virologic failure, and >10% of the subgroup of children with treatment failure in whom genotyping was performed demonstrated multiple HIV drug resistance mutations. Neither clinical condition nor CD4 cells were good indicators for treatment failure.

Antiretroviral drug resistance profiles and response to second-line therapy among HIV type 1-infected Ugandan children

We sought to determine the pattern of resistance-associated mutations (RAMs) among HIV-1-infected children failing first-line antiretroviral therapy (ART) and ascertain their response to second-line regimens in 48 weeks of follow-up. The design involved a cohort study within an HIV care program. We studied records of 142 children on ART with virological failure to first-line ART and switched to second-line ART with prior genotypic resistance testing. The pattern of RAMs was determined in frequency runs and the factors associated with accumulation of≥3 thymidine analogue mutations (TAMs) and K103N were determined using multivariate logistic models. Changes in weight, height, CD4, and viral load at weeks 24 and 48 after switch to second-line therapy were determined using descriptive statistics. The children were mean age 10.9±4.6 years and 55.6% were male. The commonest nucleoside reverse transcriptase inhibitor (NRTI) RAM was M184V in 129/142 (90.8%) children. TAMs,≥3 TAMs, 69 insertion complex, K65R/N, and Q151M were observed in 43.0%, 10.6%, 18.3%, 2.8%, and 2.1% of the children, respectively. The commonest nonnucleoside reverse transcriptase inhibitor (NNRTI) RAM was K103N in 72/142 (50.7%) children. The starting ART regimen was associated with accumulation of both≥3 TAMs (p=0.046) and K103N (p<0.0001), while a history of poor adherence was associated with K103N accumulation (p=0.0388). After 24 weeks and 48 weeks of follow-up on lopinavir-ritonavir based second-line ART, 86/108 (79.6%) and 84.5% (87/103) of the children had viral loads<400 copies/ml, respectively. The mean CD4 absolute count increased by 173 cells/μl and 267cells/μl at weeks 24 and 48, respectively. Increments were also observed in mean weight (1.6 kg and 4.3 kg) and height (1.8 cm and 5.8 cm) at weeks 24 and 48, respectively. Multiple RAMs were observed among HIV-1-infected children with virological failure on first-line ART with M184V and K103N most frequent. The children responded favorably to boosted PI-based second-line ART.

Surveillance of HIV drug resistance in children receiving antiretroviral therapy: a pilot study of the World Health Organization's generic protocol in Maputo, Mozambique

Between 2007 and 2008, the Mozambique Ministry of Health conducted an assessment of human immunodeficiency virus drug resistance (HIVDR) using World Health Organization (WHO) methods in a cohort of children initiating antiretroviral therapy (ART) at the main pediatric ART referral center in Mozambique. It was shown that prior to ART initiation 5.4% of children had HIVDR that was associated with nevirapine perinatal exposure (P < .001). Twelve months after ART initiation, 77% had viral load suppression (<1000 copies/mL), exceeding the WHO target of ≥ 70%; 10.3% had HIVDR at 12 months. Baseline HIVDR (P = .04), maternal prevention of mother-to-child transmission (P = .02), and estimated days of missed medication (P = .03) predicted HIVDR at 12 months. As efforts to eliminate pediatric AIDS are intensified, implementation of ritonavir-boosted protease inhibitor regimens in children with prevention of mother-to-child transmission exposure may reduce risk of virological failure in our setting.