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

Virological outcomes and genotypic resistance on dolutegravir-based antiretroviral therapy versus standard of care in children and adolescents: a secondary analysis of the ODYSSEY trial

BACKGROUND

ODYSSEY showed superior efficacy for dolutegravir-based antiretroviral therapy (ART) versus standard of care (SOC) in children living with HIV starting first-line or second-line ART aged 4 weeks or older. Here, we aim to compare virological outcomes and resistance in the dolutegravir group versus SOC for first-line and second-line ART up to 96 weeks.

METHODS

ODYSSEY was an open-label, multicentre, randomised, non-inferiority trial done in 29 centres in seven countries (Germany, Spain, South Africa, Thailand, the UK, Uganda, and Zimbabwe). ODYSSEY recruited children living with HIV aged at least 28 days and younger than 18 years, weighing at least 3 kg, starting first-line ART (ODYSSEY A), or switching to second-line therapy after treatment failure (ODYSSEY B). Children were randomly assigned (1:1) to dolutegravir plus two nucleoside or nucleotide reverse transcriptase inhibitors (NRTIs; dolutegravir group) versus the SOC group (non-nucleoside reverse transcriptase inhibitor [NNRTI], boosted protease inhibitor, or non-dolutegravir integrase strand-transfer inhibitor, plus two NRTIs). Two randomised cohorts were combined in this exploratory analysis: children weighing at least 14 kg were enrolled between Sept 20, 2016, and June 22, 2018, and children weighing less than 14 kg were enrolled between July 5, 2018, and Aug 26, 2019. Virological failure was defined as an inadequate virological response at week 24 with an ART switch or confirmed HIV-1 RNA viral load of at least 400 copies per mL after week 36. Virological suppression was defined as two consecutive viral loads of less than 400 copies per mL and was compared between groups, including an ART switch and death as competing risks. Children with virological failure were tested for post-failure genotypic resistance, with baseline results used to identify emergent resistance. Development of emergent resistance was a secondary trial outcome and all other outcomes are exploratory. ODYSSEY was registered with ClinicalTrials.gov (NCT02259127), EUDRACT (2014-002632-14), and ISRCTN (ISRCTN91737921).

FINDINGS

In ODYSSEY at enrolment, 381 participants started first-line ART (ODYSSEY A: 189 in the dolutegravir group and 192 in the SOC group) and 407 participants started second-line ART (ODYSSEY B: 202 in the dolutegravir group and 205 in the SOC group). 72 participants in ODYSSEY A and 13 participants in ODYSSEY B weighed less than 14 kg. 401 (51%) of 788 participants were female and 387 (49%) were male. Virological suppression occurred significantly earlier in the dolutegravir group (adjusted [cause-specific] hazard ratio [HR] 1·57 [95% CI 1·35 to 1·83]; p<0·0001). Overall, 51 (13%) participants had virological failure by 96 weeks in the dolutegravir group versus 86 (22%) in the SOC group (including 18 [10%] vs 43 [22%] in ODYSSEY A and in 33 [16%] vs 43 [21%] in ODYSSEY B; adjusted HR 0·56 [0·40 to 0·79]; p=0·0011). Among ODYSSEY B participants starting dolutegravir, virological failure was higher in children starting zidovudine (HR 2·22 [1·01 to 4·88]; p=0·048) and similar in those starting tenofovir disoproxil fumarate (1·19 [0·50 to 2·83]; p=0·70) compared with abacavir. Time to virological suppression was marginally faster in participants receiving second-line dolutegravir and abacavir with high-level abacavir resistance at baseline compared with those with no, low-level, intermediate-level resistance (cause-specific HR 1·70 [1·01 to 2·85]; p=0·046); and failure rates by week 96 were similar (HR 0·90 [0·23 to 3·61]; p=0·88). An estimated 1% (95% CI 0 to 2) of participants in the dolutegravir group versus 20% (14 to 26) in the SOC group in ODYSSEY A had emergent resistance to at least one drug-class within their first-line regimen (risk difference -20% [-25 to -14]; p<0·0001); 4% (1 to 6) versus 5% (2 to 8) had resistance to drug within their initial second-line regimen (risk difference -1% [-5 to 3]; p=0·60). 3% (0 to 5) of participants in the dolutegravir group had emergent integrase strand-transfer inhibitors resistance compared with 3% (1 to 6) of participants in the SOC group who had emergent resistance to the anchor drug (risk difference 0% [-4 to 3]; p=0·78).

INTERPRETATION

Dolutegravir led to faster virological suppression and lower risk of virological failure than NNRTIs and boosted protease inhibitor-based SOC. Participants starting second-line dolutegravir-based ART with an abacavir or tenofovir backbone were at lower risk of virological failure than those starting zidovudine. During first-line therapy, dolutegravir protected against emergent resistance; starting second-line therapy, the risk of emergent resistance to nucleoside reverse transcriptase inhibitor backbone, and anchor drugs, was similar among participants starting dolutegravir within their second-line regimen and those starting mainly boosted protease inhibitor-based SOC.

FUNDING

Penta Foundation, ViiV Healthcare, and UK Medical Research Council.

Outcomes of HIV-infected children on antiretroviral therapy for at least 10 years at the Essos Hospital Centre, Cameroon: contributing to the elimination of paediatric AIDS in tropical settings

Evidence on long-term outcomes of children receiving antiretroviral therapy (ART) in low- and middle-income countries (LMICs) is of utmost importance to optimize current and future therapeutic strategies for HIV. We sought to ascertain the long-term responses among ART-experienced children and their potential implications. A retrospective, observational, facility-based cohort study was conducted among 136 ART-experienced children monitored for 10 years (2007-2017) at the Essos Hospital Centre in Yaoundé, Cameroon. Primary outcomes were good clinical response defined as the World Health Organization (WHO) clinical stage 1/2, immune restoration as CD4 >500 cells/mm3, viral suppression (VS) as viral load (VL) <1000, or viral undetectability as VL <40 copies/ml at the last follow-up and their predictors (P < .05). At ART initiation among the 90 eligible children, median (interquartile range) age was 29.5 (11-60) months, 53.3% were males, 34.5% were at WHO clinical stage 1/2, median-CD4 was 497 cells/mm3, and initial ART-regimens were mainly zidovudine-lamivudine-nevirapine (85.5%) and zidovudine-lamivudine-efavirenz (12.2%). After 10 years of follow-up, 36.7% were switched to protease-based ART regimens, those at WHO clinical stage 1/2 improved to 75.5%; median-CD4 increased to 854 cells/mm3; 83.3% achieved VS, while only 10% achieved viral undetectability. Following multivariate analysis, no predictor of VS or immune recovery was identified (P > .05). In this LMIC, long-term outcomes of children on ART appear encouraging, characterized by moderate VS rate and immune recovery. However, challenges in achieving viral undetectability indicate continuous viral replication and risks of drug resistance emergence that may jeopardize effectiveness of future paediatric ART strategies.

Global, regional, and national prevalence of HIV-1 drug resistance in treatment-naive and treatment-experienced children and adolescents: a systematic review and meta-analysis

Background

Despite significant reductions in mother-to-child HIV-1 transmission risks due to the advancements and scale-up of antiretroviral therapy (ART), the global burden of HIV-1 drug resistance (HIVDR) in treatment-naive and treatment-experienced children and adolescents remains poorly understood. In this study, we conducted a systematic review and meta-analysis to estimate the prevalence of HIVDR in these populations globally, regionally, and at the country level.

Methods

We systematically searched PubMed, Embase, and Web of Science for studies reporting HIVDR in treatment-naive and treatment-experienced children and adolescents from inception to June 28, 2024. Eligible studies reported at least ten successfully genotyped cases. We excluded studies where drug resistance was not reported separately for children and adults or for treatment-naive and treatment-experienced populations. The methodological quality of eligible studies was assessed, and random-effect models were used for meta-analysis to determine the pooled overall and regimen-specific prevalence of one or more HIVDR mutations in these populations globally, regionally, or at the country level. This study is registered with PROSPERO under the number CRD42023424483.

Findings

Of 2282 records identified, 136 studies (28,539 HIV-1-infected children from 52 countries) were included for analysis. The overall prevalence of HIVDR is 26.31% (95% CI, 20.76-32.25) among treatment-naive children and 74.16% (95% CI, 67.74-80.13) among treatment-experienced children (p < 0.0001). HIVDR varied widely across subregion with the highest prevalence in Southern Africa (37.80% [95% CI, 26.24-50.08]) and lowest in South America (11.79% [95% CI, 4.91-20.84]) for treatment-naive children while highest in Asia (80.85% [95% CI, 63.76-93.55]) and lowest in Europe (54.39% [95% CI, 28.61-79.03]) for treatment-experienced children. The proportion of viral failure (VF) presented positive correlation with DR prevalence for treatment-experienced children, which increased from 61.23% (95% CI, 47.98-73.72) in proportion of VF <50%-81.17% (95% CI, 71.57-89.28) in proportion of 100%. Meta-regression analysis for both groups showed that only age (naive: p = 0.0005; treated: p < 0.0001) was the sources of heterogeneity. Non-nucleoside reverse transcriptase inhibitor (NNRTI) resistances were the most seen mutations among the treatment-naive group, with the HIVDR prevalence more than 10% in Southern Africa, Western and Central Africa, Eastern Africa, Asia, and North America. Both nucleoside reverse transcriptase inhibitor (NRTI) and NNRTI resistances were commonly seen among the treatment-experienced group, varying from 36.33% (95% CI, 11.96-64.93) in North America to 77.54% (95% CI, 62.70-89.58) in South America for NRTI and from 39.98% (95% CI, 13.47-69.97) in Europe to 68.86 (95% CI, 43.91-89.17) in Asia for NNRTI, respectively.

Interpretation

This study underscores the significant burden of HIVDR among children and adolescents worldwide, particularly pronounced in sub-Saharan Africa and low-income countries. It emphasizes the critical importance of surveillance in all HIV-1-infected children and advocates for the adoption of dolutegravir (DTG) or other optimal formulations as first-line ART in settings where NNRTI resistance exceeds the WHO's 10% threshold. DTG's high resistance barrier, potent antiviral efficacy, and favorable safety profile makes it a superior choice for managing drug-resistant HIV-1, surpassing traditional antiretroviral therapies.

Funding

This work was supported by the Science and Technology Innovation Committee of Shenzhen Municipality (No. JCYJ20220531102202005) and the Natural Science Foundation of Guangdong Province (No. 2024A1515012118).

Determinants of Immunovirological Response among Children and Adolescents Living with HIV-1 in the Central Region of Cameroon

About 90% of new HIV-1 infections in children occur in sub-Saharan Africa, where treatment monitoring remains suboptimal. We sought to ascertain factors associated with immunovirological responses among an ART-experienced paediatric population in Cameroon. A laboratory-based and analytical study was conducted from January 2017 throughout December 2020 wherein plasma viral load (PVL) analyses and CD4 cell counts were performed. Viral suppression (VS) was defined as PVL < 1000 copies/mL and immunological failure (IF) as CD4 < 500 cells/µL for participants ≤5 years and CD4 < 250 cells/µL for those >5 years; p < 0.05 was considered statistically significant. Overall, 272 participants were enrolled (median age: 13 [9-15.5] years; 54% males); median ART duration 7 [3-10] years. Globally, VS was achieved in 54.41%. VS was 56.96% in urban versus 40.48% in rural areas (p = 0.04). IF was 22.43%, with 15.79% among participants ≤5 years and 22.92% among those >5 years (p = 0.66). IF was 20.43% in urban versus 33.33% in rural areas (p = 0.10). Following ART, IF was 25.82% on first-line (non-nucleoside reverse transcriptase inhibitors; NNRTI-based) versus 10.17% on second-line (protease inhibitor-based) regimens (p = 0.01). Interestingly, IF was 7.43% among virally suppressed versus 40.32% among virally unsuppressed participants (p < 0.0001). A low VS indicates major challenges in achieving AIDS' elimination in this paediatric population, especially in rural settings and poor immune statuses. Scaling up NNRTI-sparing regimens alongside close monitoring would ensure optimal therapeutic outcomes.

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.

Viral Response among Early Treated HIV Perinatally Infected Infants: Description of a Cohort in Southern Mozambique

Early initiation of antiretroviral therapy and adherence to achieve viral load suppression (VLS) are crucial for reducing morbidity and mortality of perinatally HIV-infected infants. In this descriptive cohort study of 39 HIV perinatally infected infants, who started treatment at one month of life in Mozambique, we aimed to describe the viral response over 2 years of follow up. VLS ≤ 400 copies/mL, sustained VLS and viral rebound were described using a Kaplan-Meier estimator. Antiretroviral drug transmitted resistance was assessed for a sub-group of non-VLS infants. In total, 61% of infants reached VLS, and 50% had a rebound. Cumulative probability of VLS was 36%, 51%, and 69% at 6, 12 and 24 months of treatment, respectively. The median duration of VLS was 7.4 months (IQR 12.6) and the cumulative probability of rebound at 6 months was 30%. Two infants had resistance biomarkers to drugs included in their treatment regimen. Our findings point to a low rate of VLS and high rate of viral rebound. More frequent viral response monitoring is advisable to identify infants with rebound and offer timely adherence support. It is urgent to tailor the psychosocial support model of care to this specific age group and offer differentiated service delivery to mother-baby pairs.

Rate of virological failure and HIV-1 drug resistance among HIV-infected adolescents in routine follow-up on health facilities in Cameroon

The objective of this study was to determine the rates of virological failure (VF) and HIV drug resistance (HIVDR) amongst adolescents on antiretroviral Therapy (ART). A retrospectively designed study was conducted in 10 healthcare centers for adolescents living with HIV (ALHIV) in the two main cities of Cameroon (Yaoundé and Douala), from November 2018 to May 2019. Sociodemographic, clinical, therapeutic and laboratory parameters were collected from medical records. All enrolled ALHIV had viral load (VL) measurements following the national guidelines. All patients with a VL ≥ 1000 copies/ml were called to perform genotyping tests. The chi-square test was used to determine the factors associated with VF. Out of the 1316 medical records of ALHIV, we included 1083 ALHIV having a VL result. Among them, 276 (25.5%) were experiencing VF, and VF was significantly higher in ALHIV with suboptimal adherence (p<0.001), older adolescents (p<0.05), those who lived outside the city where they were receiving ART (p<0.006), severely immunocompromised (p<0.01) and started ART at infancy (p<0.02). Among the 45/276 (16.3%) participants with an available genotyping resistance testing (GRT) result, the overall rate of HIVDR was 93.3% (42/45). The most common mutations were K103N (n = 21/42, 52.3%) resulting in high-level resistance to Efavirenz and Nevirapine, followed by M184V (n = 20/42, 47.6%) and thymidine analog mutations (n = 15/42, 35.7%) associated with high-level resistance to Lamivudine and Zidovudine respectively. The high rate of VF and HIVDR among ALHIV regularly followed in health facilities in Cameroon highlights the need to develop interventions adapted to an adolescent-centered approach to preserve future ART options.

The impact of viraemia on inflammatory biomarkers and CD4+ cell subpopulations in HIV-infected children in sub-Saharan Africa

OBJECTIVE

To determine the impact of virological control on inflammation and cluster of differentiation 4 depletion among HIV-infected children initiating antiretroviral therapy (ART) in sub-Saharan Africa.

DESIGN

Longitudinal cohort study.

METHODS

In a sub-study of the ARROW trial (ISRCTN24791884), we measured longitudinal HIV viral loads, inflammatory biomarkers (C-reactive protein, tumour necrosis factor alpha, interleukin 6 (IL-6), soluble CD14) and (Uganda only) whole blood immunophenotype by flow cytometry in 311 Zimbabwean and Ugandan children followed for median 3.5 years on first-line ART. We classified each viral load measurement as consistent suppression, blip/post-blip, persistent low-level viral load or rebound. We used multi-level models to estimate rates of increase or decrease in laboratory markers, and Poisson regression to estimate the incidence of clinical events.

RESULTS

Overall, 42% children experienced viral blips, but these had no significant impact on immune reconstitution or inflammation. Persistent detectable viraemia occurred in one-third of children and prevented further immune reconstitution, but had little impact on inflammatory biomarkers. Virological rebound to ≥5000 copies/ml was associated with arrested immune reconstitution, rising IL-6 and increased risk of clinical disease progression.

CONCLUSIONS

As viral load testing becomes more available in sub-Saharan Africa, repeat testing algorithms will be required to identify those with virological rebound, who need switching to prevent disease progression, whilst preventing unnecessary second-line regimen initiation in the majority of children with detectable viraemia who remain at low risk of disease progression.

Prevalence of viral load suppression, predictors of virological failure and patterns of HIV drug resistance after 12 and 48 months on first-line antiretroviral therapy: a national cross-sectional survey in Uganda

Objectives

We implemented the WHO cross-sectional survey protocol to determine rates of HIV viral load (VL) suppression (VLS), and weighted prevalence, predictors and patterns of acquired drug resistance (ADR) in individuals with virological failure (VF) defined as VL ≥1000 copies/mL.

Methods

We enrolled 547 and 1064 adult participants on first-line ART for 12 (±3) months (ADR12) and ≥48 months (ADR48), respectively. Dried blood spots and plasma specimens were collected for VL testing and genotyping among the VFs.

Results

VLS was 95.0% (95% CI 93.4%–96.5%) in the ADR12 group and 87.9% (95% CI 85.0%–90.9%) in the ADR48 group. The weighted prevalence of ADR was 96.1% (95% CI 72.9%–99.6%) in the ADR12 and 90.4% (95% CI 73.6–96.8%) in the ADR48 group, out of the 30 and 95 successful genotypes in the respective groups. Initiation on a zidovudine-based regimen compared with a tenofovir-based regimen was significantly associated with VF in the ADR48 group; adjusted OR (AOR) 1.96 (95% CI 1.13–3.39). Independent predictors of ADR in the ADR48 group were initiation on a zidovudine-based regimen compared with tenofovir-based regimens, AOR 3.16 (95% CI 1.34–7.46) and ART duration of ≥82 months compared with <82 months, AOR 1.92 (95% CI 1.03–3.59).

Conclusions

While good VLS was observed, the high prevalence of ADR among the VFs before they underwent the recommended three intensive adherence counselling (IAC) sessions followed by repeat VL testing implies that IAC prior to treatment switching may be of limited benefit in improving VLS.

Alarming rates of virological failure and HIV-1 drug resistance amongst adolescents living with perinatal HIV in both urban and rural settings: evidence from the EDCTP READY-study in Cameroon

OBJECTIVES

Adolescents living with perinatal HIV infection (ALPHI) experience persistently high mortality rates, particularly in resource-limited settings. It is therefore clinically important for us to understand the therapeutic response, acquired HIV drug resistance (HIVDR) and associated factors among ALPHI, according to geographical location.

METHODS

A study was conducted among consenting ALPHI in two urban and two rural health facilities in the Centre Region of Cameroon. World Health Organization (WHO) clinical staging, self-reported adherence, HIVDR early warning indicators (EWIs), immunological status (CD4 count) and plasma viral load (VL) were assessed. For those experiencing virological failure (VF, VL ≥ 1000 copies/mL), HIVDR testing was performed and interpreted using the Stanford HIV Drug Resistance Database v.8.9-1.

RESULTS

Of the 270 participants, most were on nonnucleoside reverse transcriptase inhibitor (NNRTI)-based regimens (61.7% urban vs. 82.2% rural), and about one-third were poorly adherent (30.1% vs. 35.1%). Clinical failure rates (WHO-stage III/IV) in both settings were < 15%. In urban settings, the immunological failure (IF) rate (CD₄  < 250 cells/μL) was 15.8%, statistically associated with late adolescence, female gender and poor adherence. The VF rate was 34.2%, statistically associated with poor adherence and NNRTI-based antiretroviral therapy. In the rural context, the IF rate was 26.9% and the VF rate was 52.7%, both statistically associated with advanced clinical stages. HIVDR rate was over 90% in both settings. EWIs were delayed drug pick-up, drug stock-outs and suboptimal viral suppression.

CONCLUSIONS

Poor adherence, late adolescent age, female gender and advanced clinical staging worsen IF. The VF rate is high and consistent with the presence of HIVDR in both settings, driven by poor adherence, NNRTI-based regimen and advanced clinical staging.

Virologic response of treatment experienced HIV-infected Ugandan children and adolescents on NNRTI based first-line regimen, previously monitored without viral load

Background

Many HIV-infected African children gained access to antiretroviral treatment (ART) through expansion of PEPFAR programs since 2004 and introduction of “Test and Treat” WHO guidelines in 2015. As ART access increases and children transition from adolescence to adulthood, treatment failure is inevitable. Viral load (VL) monitoring in Uganda was introduced in 2016 replacing clinical monitoring. However, there’s limited data on the comparative effectiveness of these two strategies among HIV-infected children in resource-limited settings (RLS).

Methods

HIV-infected Ugandan children aged 1–12 years from HIV-care programs with > 1 year of first-line ART using only immunologic and clinical criteria to monitor response to treatment were screened in 2010. Eligible children were stratified by VL ≤ 400 and > 400 copies/ml randomized to clinical and immunological (control) versus clinical, immunological and VL monitoring to determine treatment failure with follow-up at 12, 24, 36, and 48 weeks. Plasma VL was analyzed retrospectively for controls. Mixed-effects logistic regression models were used to compare the prevalence of viral suppression between study arms and identify factors associated with viral suppression.

Results

At baseline all children (n = 142) were on NNRTI based ART (75% Nevirapine, 25% efavirenz). One third of ART-experienced children had detectable VL at baseline despite high CD4%. Median age was 6 years (interquartile range [IQR]: 5–9) and 43% were female. Overall, the odds of viral suppression were not different between study arms: (arm by week interaction, p = 0.63), adjusted odds ratio [aOR]: 1.07; 95%CI: 0.53, 2.17, p = 0.57) and did not change over time (aOR: 0 vs 24 week: 1.15; 95% CI: 0.91, 1.46, p = 0.24 and 0 vs 48 weeks: 1.26; 95%CI: 0.92, 1.74, p = 0.15). Longer duration of a child’s ART exposure was associated with lower odds of viral suppression (aOR: 0.61; 95% CI: 0.42, 0.87, p < .01). Only 13% (9/71) of children with virologic failure were switched to second-line ART, in spite of access to real-time VL.

Conclusion

With increasing ART exposure, viral load monitoring is critical for early detection of treatment failure in RLS. Clinicians need to make timely informed decisions to switch failing children to second-line ART.

Trial registration

ClinicalTrials.gov NCT04489953, 28 Jul 2020. Retrospectively registered. (https://register.clinicaltrials.gov).

Pediatric Antiretroviral Therapy

Human immunodeficiency virus (HIV) is one of the most serious pediatric infectious diseases, affecting around 3 million children and adolescents worldwide. Lifelong antiretroviral treatment (ART) provides multiple benefits including sustained virologic suppression, restoration and preservation of immune function, decreased morbidity and mortality, and improved quality of life. However, access to ART, particularly among neonates and young infants, continues to be challenging due to limited number of suitable formulations and limited access to pediatric ARV drug. Moreover, children and adolescents living with HIV may experience long-term HIV- and ART-associated comorbidities including cardiovascular, renal, neurological, and metabolic complications. We provide an overview of currently available formulations, dosing, and safety considerations for pediatric antiretroviral drugs by drug classes and according to the three age groups including neonates, children, and adolescents.

Long-term virological outcomes, failure and acquired resistance in a large cohort of Ugandan children

OBJECTIVES

To evaluate long-term virological failure (VF) and drug resistance among HIV-infected Ugandan children on first-line ART.

METHODS

In a multicentre prospective cohort study, viral load (VL) and drug resistance mutations (DRMs) were investigated at baseline and 6 monthly intervals in children (age ≤ 12 years). VF (two consecutive VLs >1000 copies/mL or death after 6 months of ART) was defined as early VF (0-24 months of ART) or late VF (25-48 months of ART). An active regimen was defined as partially active if the genotypic susceptibility score (GSS) was <3.

RESULTS

Between 2010 and 2011, 316 children were enrolled. Viral suppression was achieved in 75.8%, 71.5%, 72.6% and 69.2% at 12, 24, 36 and 48 months. VF occurred in 111/286 (38.8%), of which 67.6% was early and 32.4% late VF. Early VF was associated with a partially active regimen at baseline (OR 6.0, 95% CI 1.9-18.5), poor adherence (OR 3.1, 95% CI 1.3-7.4) and immunodeficiency (OR 3.3, 95% CI 1.1-10.2). Late VF was associated with age >3 years (OR 2.5, 95% CI 1.0-6.6) and WHO stage 3/4 (OR 4.2, 95% CI 1.4-13.4). Acquired DRMs were detected in 27.0% before 24 months, versus 14.4% after 24 months (P < 0.001). A total of 92.2% of the children with early VF, versus 56.2% with late VF, had a partially active regimen (P < 0.001).

CONCLUSIONS

VF rates were high, occurred predominantly in the first 24 months and appeared to increase again in year four. Risk factors and patterns of early VF/DRMs were different from those of late VF/DRMs. Virological control may improve by close monitoring and prompt switching to second-line therapy in the first 24 months. Late VF may be prevented by early start of ART.

Characterization of HIV-1 subtypes and drug resistance mutations in Henan Province, China (2017-2019)

Human immunodeficiency virus type 1 (HIV-1) infection remains a severe public health problem worldwide. In this study, we investigated the distribution of HIV-1 subtypes and the prevalence of drug resistance mutations (DRMs) among patients with HIV-1 infection in Henan Province, China. HIV-1 strains in blood samples taken from inpatients and outpatients visiting the Sixth People’s Hospital of Zhengzhou from August 2017 to July 2019 with a viral load (VL) greater than 1000 copies/ml were subjected to subtype and DRMs analysis. Out of a total of 769 samples, subtype and DRM data were obtained from 657 (85.43%) samples. Phylogenetic analysis based on partial pol gene sequences indicated that the most commonly found genotype was subtype B (45.51%, 299/657), followed by CRF01_AE (28.61%, 188/657), CRF07_BC (15.68%, 103/657), CRF08_BC (0.76%, 5/657), C (0.61%, 4/657), A (0.30%, 2/657), and others (8.52%, 56/657). Circulating recombinant forms (CRFs) were most commonly found in patients who were naïve to antiretroviral treatment (ART) (68.67%, 160/233). The percentage of patients with one or more major drug-resistance mutations was 50.99% (335/657), and it was 6.44% (15/233) in ART-naive patients that were primarily infected with subtype B (17.74%). Resistance mutations were most common at codons 65, 103, 106, 184, and 190 of the reverse transcriptase gene and codon 46 of the protease gene. Our study provides detailed information about the distribution of HIV-1 subtypes and the incidence of drug resistance mutations of different subtypes in ART-experienced and naïve patients. This can guide policymakers in making decisions about treatment strategies against HIV-1.

Factors associated with high-risk low-level viremia leading to virologic failure: 16-year retrospective study of a Chinese antiretroviral therapy cohort

BACKGROUND

Low level viremia (LLV) often occurs during antiretroviral therapy (ART) against HIV-1. However, whether LLV increases the risk of virologic failure (VF) is controversial because of the non-uniform definitions of LLV and VF.

METHODS

A long-term first line regimen ART cohort from 2002 to 2018 from Shenyang, northeast China, was retrospectively studied. All participants were followed up every 3 to 6 months to evaluate the treatment effect. The high-risk LLV subgroups leading to VF (with strict standards) were explored with Cox proportional hazards model and linear mixed-effect model. The association factors of high-risk LLV were further explored using multivariate logistic regression analyses.

RESULTS

A total of 2155 HIV-1 infected participants were included; of these, 38.7% showed LLV. Both high level LLV (HLLV) and any other level LLV coupled with high level blip (HLB) showed higher risk of VF (hazards ratios, HR_HLLV = 5.93, and HR_HLB = 2.84, p <  0.05 respectively). Moreover, HR increased with prolonged duration of LLV. Independent factors associated with high-risk LLV included the zenith baseline viral load (VL) above 6 log copies/ml (aOR = 3.49, p = 0.002), nadir baseline CD4 + T cell counts below 200 cells/mm³ (aOR = 1.78, p = 0.011), Manchu (aOR = 2.03, p = 0.003), ART over 60 months (aOR = 1.81, p = 0.004), AZT + 3TC + NVP (aOR = 2.26, p <  0.001) or DDI-based regimen (aOR = 9.96, p = 0.002), and subtype B' infection (aOR = 8.22, p = 0.001).

CONCLUSIONS

In case of VF with strict standards, high-risk LLV leading to VF includes VL above 400 copies/ml, occurring at least once. Serious laboratory indicators or advanced stage of infection, long term ART and subtype B' infection might also predict the occurrence of high-risk LLV.

Getting Treatment and Care Services Right for Children and Adolescents to Reach High Viral Suppression

In August 2014, PEPFAR and the Children's Investment Fund Foundation launched the Accelerating Children's HIV/AIDS Treatment (ACT) initiative with the aim of doubling the number of children on antiretroviral treatment in 9 African countries. Increasing rates of pretreatment drug resistance and use of suboptimal treatment regimens and formulations result in poor adherence and high rates of viral failure. Supporting adherence and ensuring appropriate treatment monitoring are needed to maximize duration of first-line treatment and enable timely sequencing to subsequent lines of antiretroviral treatment. Although timely antiretroviral treatment is the core of clinical care for infants, children and adolescents living with HIV, ensuring a broader package of biomedical and non-biomedical interventions is also required to address highly prevalent comorbidities among children living with HIV. Providing such a comprehensive package has been challenging for health care workers who lack the necessary skills and confidence to care for pediatric populations. Efforts to simplify clinical management and specific training and mentorship are needed to address these challenges. In this article, we review the progress made during the ACT initiative and the persistent challenges in achieving and maintaining virological suppression across the age spectrum. We identify innovations needed to build on the success of the ACT initiative. Despite the challenges, achieving high levels of virological suppression in children and adolescents is possible. The complexity of pediatric HIV treatment can be offset as antiretroviral regimens become more effective, tolerable, and easier to prescribe and administer. Meanwhile, basic programmatic elements to address comorbidities as well as support health care workers remain critical. In this article we review the progress made through the ACT initiative, as well as identify innovations needed to address persistent challenges to viral suppression across the age spectrum.

Incidence of switching to second-line antiretroviral therapy and associated factors in children with HIV: an international cohort collaboration

BACKGROUND

Estimates of incidence of switching to second-line antiretroviral therapy (ART) among children with HIV are necessary to inform the need for paediatric second-line formulations. We aimed to quantify the cumulative incidence of switching to second-line ART among children in an international cohort collaboration.

METHODS

In this international cohort collaboration study, we pooled individual patient-level data for children younger than 18 years who initiated ART (two or more nucleoside reverse-transcriptase inhibitors [NRTI] plus a non-NRTI [NNRTI] or boosted protease inhibitor) between 1993 and 2015 from 12 observational cohort networks in the Collaborative Initiative for Paediatric HIV Education and Research (CIPHER) Global Cohort Collaboration. Patients who were reported to be horizontally infected with HIV and those who were enrolled in trials of treatment monitoring, switching, or interruption strategies were excluded. Switch to second-line ART was defined as change of one or more NRTI plus either change in drug class (NNRTI to protease inhibitor or vice versa) or protease inhibitor change, change from single to dual protease inhibitor, or addition of a new drug class. We used cumulative incidence curves to assess time to switching, and multivariable proportional hazards models to explore patient-level and cohort-level factors associated with switching, with death and loss to follow-up as competing risks.

FINDINGS

At the data cutoff of Sept 16, 2015, 182 747 children with HIV were included in the CIPHER dataset, of whom 93 351 were eligible, with 83 984 (90·0%) from sub-Saharan Africa. At ART initiation, the median patient age was 3·9 years (IQR 1·6-6·9) and 82 885 (88·8%) patients initiated NNRTI-based and 10 466 (11·2%) initiated protease inhibitor-based regimens. Median duration of follow-up after ART initiation was 26 months (IQR 9-52). 3883 (4·2%) patients switched to second-line ART after a median of 35 months (IQR 20-57) of ART. The cumulative incidence of switching at 3 years was 3·1% (95% CI 3·0-3·2), but this estimate varied widely depending on the cohort monitoring strategy, from 6·8% (6·5-7·2) in settings with routine monitoring of CD4 (CD4% or CD4 count) and viral load to 0·8% (0·6-1·0) in settings with clinical only monitoring. In multivariable analyses, patient-level factors associated with an increased likelihood of switching were male sex, older age at ART initiation, and initial NNRTI-based regimen (p<0·0001). Cohort-level factors that increased the likelihood of switching were higher-income country (p=0·0017) and routine or targeted monitoring of CD4 and viral load (p<0·0001), which was associated with a 166% increase in likelihood of switching compared with CD4 only monitoring (subdistributional hazard ratio 2·66, 95% CI 2·22-3·19).

INTERPRETATION

Our global paediatric analysis found wide variations in the incidence of switching to second-line ART across monitoring strategies. These findings suggest the scale-up of viral load monitoring would probably increase demand for paediatric second-line ART formulations.

FUNDING

International AIDS Society-CIPHER.

Growth and pubertal development in HIV-infected adolescents

PURPOSE OF REVIEW

We present an overview of recent research in the inter-related areas of growth and pubertal development among adolescents with HIV. Growth deficits early in childhood can lead to delayed puberty, with subsequent effects on pubertal growth spurts and bone health.

RECENT FINDINGS

Impaired growth remains a critical concern, particularly in low-resource settings, where stunting, wasting and underweight remain pervasive. Antiretroviral treatment (ART) initiation results in improved growth, with greatest growth recovery in the first years and more improvement in weight than in height. However, even years after ART initiation, growth deficits persist in low-resource settings (LRS), and adolescents appear at particularly increased risk. The high prevalence of stunting translates to delays in pubertal onset and sexual maturity. In contrast, HIV-infected adolescents in developed countries do not demonstrate persistent wasting, yet still have delayed pubertal development. Impaired growth increases the risk for mortality, virologic failure, and abnormal bone health, as well as increased depression and stigma.

SUMMARY

Early initiation of ART across all age groups regardless of immunological status is essential for restoring growth. Coordination of ART initiation, nutritional supplementation programs, and concurrent prophylaxis is required to ameliorate growth deficits and pubertal delays, particularly in LRS.

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

OBJECTIVE

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

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.

Influence of Phosphatidylinositol-3-Kinase/Protein Kinase B-Mammalian Target of Rapamycin Signaling Pathway on the Neuropathic Pain Complicated by Nucleoside Reverse Transcriptase Inhibitors for the Treatment of HIV Infection

Background:

Nucleoside reverse transcriptase inhibitors (NRTIs) are the earliest and most commonly used anti-human immunodeficiency virus drugs and play an important role in high active antiretroviral therapy. However, NRTI drug therapy can cause peripheral neuropathic pain. In this study, we aimed to investigate the mechanisms of rapamycin on the pain sensitization of model mice by in vivo experiments to explore the effect of mammalian target of rapamycin (mTOR) in the pathogenesis of neuropathic pain caused by NRTIs.

Methods:

Male Kun Ming (KM) mice weighing 20–22 g were divided into control, 2 mg/kg rapamycin, 12 mg/kg stavudine, and CMC-Na groups. Drugs were orally administered to mice for 42 consecutive days. The von Frey filament detection and thermal pain tests were conducted on day 7, 14, 21, 28, 35, and 42 after drug administration. After the last behavioral tests, immunohistochemistry and western blotting assay were used for the measurement of mTOR and other biomarkers. Multivariate analysis of variance was used.

Results:

The beneficial effects of rapamycin on neuropathic pain were attributed to a reduction in mammalian target of rapamycin sensitive complex 1 (mTORC1)-positive cells (70.80 ± 2.41 vs. 112.30 ± 5.66, F = 34.36, P < 0.01) and mTORC1 activity in the mouse spinal cord. Mechanistic studies revealed that Protein Kinase B (Akt)/mTORsignaling pathway blockade with rapamycin prevented the phosphorylation of mTORC1 in stavudine-intoxicated mice (0.72 ± 0.04 vs. 0.86 ± 0.03, F = 4.24, P = 0.045), as well as decreased the expression of phospho-p70S6K (0.47 ± 0.01 vs. 0.68 ± 0.03, F = 6.01, P = 0.022) and phospho-4EBP1 (0.90 ± 0.04 vs. 0.94 ± 0.06, F = 0.28, P = 0.646).

Conclusions:

Taken together, these results suggest that stavudine elevates the expression and activity of mTORC1 in the spinal cord through activating the Akt/mTOR signaling pathway. The data also provide evidence that rapamycin might be useful for the treatment of peripheral neuropathic pain.

The end of HIV: Still a very long way to go, but progress continues

In an Editorial accompanying PLOS Medicine's Special Issue on Advances in Prevention, Treatment and Cure of HIV/AIDS, Guest Editors Steven Deeks, Sharon Lewin, and Linda-Gail Bekker discuss priorities in the field and the content of the issue.