Prevalence of drug resistance in children recently diagnosed with HIV-1 infection in France (2006-17): impact on susceptibility to first-line strategies

Integrase Strand Transfer Inhibitor Use in Children with Perinatal HIV-1 Infection: A Narrative Review

Integrase strand transfer inhibitors (INSTIs), including raltegravir (RAL), dolutegravir (DTG), elvitegravir (EVG), bictegravir (BIC), and cabotegravir (CAB), are increasingly used, given excellent data on their efficacy, effectiveness, and tolerability profile in adults, while data in children are accumulating. To review the most recent evidence on the efficacy, effectiveness, safety, and resistance of INSTIs in children, a quick narrative review of the available literature data was performed using the MEDLINE/PubMed and Scopus databases, including only English-language studies, published between 2009 and 2022. Six studies (259 children) on RAL use, 17 studies (3,448 children) on DTG, 2 studies (73 children) on EVG, and 1 study (102 children) on BIC were retrieved. Results on efficacy and effectiveness were close to those reported in adult studies, suggesting similarities between children and adult population. Resistance to RAL was detected in four studies, ranging between 5.0% to 35.3% of participants. In four studies resistance to DTG occurred in 12.4% to 22% of children. Adverse events to RAL have been uncommon reported. In studies on EVG, 8% to 74% of children developed uveitis, nausea, or abdominal pain. In DTG studies, the proportion of weight gain ranged from 10% to 87%, and neuropsychiatric effects ranged 1% to 16% of participants. One BIC study reported adverse events >10% of participants. The evidence supports high efficacy and low toxicity of INSTIs in pediatric and adolescent populations.

HIV Drug Resistance in Children and Adolescents: Always a Challenge?

Purpose of Review

With the expanded roll-out of antiretrovirals for treatment and prevention of HIV during the last decade, the emergence of HIV drug resistance (HIVDR) has become a growing challenge. This review provides an overview of the epidemiology and trajectory of HIVDR globally with an emphasis on pediatric and adolescent populations.

Recent Findings

HIVDR is associated with suboptimal virologic suppression and treatment failure, leading to an increased risk of HIV transmission to uninfected people and increased morbidity and mortality among people living with HIV. High rates of HIVDR to non-nucleoside reverse transcriptase inhibitors globally are expected to decline with the introduction of the integrase strand transfer inhibitors and long-acting combination regimens, while challenge remains for HIVDR to other classes of antiretroviral drugs.

Summary

We highlight several solutions including increased HIV viral load monitoring, expanded HIVDR surveillance, and adopting antiretroviral regimens with a high-resistance barrier to decrease HIVDR. Implementation studies and programmatic changes are needed to determine the best approach to prevent and combat the development of HIVDR.

Outcomes of Integrase Inhibitor-based Antiretroviral Therapy in a Clinical Cohort of Treatment-experienced Children, Adolescents and Young Adults With HIV Infection

BACKGROUND

Data on integrase strand transfer inhibitor (INSTI) use in children, adolescents and young adults with HIV are limited. We evaluated virologic and safety outcomes following INSTI initiation among treatment-experienced children, adolescents and young adults.

METHODS

The DC Cohort is a multicenter observational study of individuals receiving HIV care in Washington, DC. This analysis included treatment-experienced participants 0-24 years of age who initiated an INSTI during 2011-2017. Viral suppression (VS) and safety outcomes were quantified. Differences in VS by age, sex and CD4 count were assessed using Kaplan-Meier curves.

RESULTS

Of 141 participants (median age 20 years; 35% <18 years; 60% male; 89% Black; 62% perinatally-infected), 35% had VS and 65% lacked VS on INSTI initiation. Dolutegravir was the most commonly prescribed INSTI (55%). Among participants without VS at INSTI initiation, 46% achieved VS after a median of 2.7 months. Participants 13-24 (vs. 0-12) years old (P = 0.011) and participants with CD4 counts <350 (vs. >500) cells/μL were less likely to achieve VS (P < 0.001). Among participants with VS at INSTI initiation, 51% sustained VS through a median of 11.0 months of follow-up; of the 49% with transient viremia, 77% later achieved VS again. There were no safety concerns associated with the use of INSTIs.

CONCLUSIONS

More than half of treatment-experienced children, adolescents and young adults with detectable viremia at INSTI initiation did not achieve VS, while half of those with prior VS experienced transient viremia. Further evaluation of long-term outcomes associated with INSTI use among children, adolescents and young adults is warranted.

Long-Acting Rilpivirine (RPV) Preexposure Prophylaxis Does Not Inhibit Vaginal Transmission of RPV-Resistant HIV-1 or Select for High-Frequency Drug Resistance in Humanized Mice

The antiretroviral drug rilpivirine was developed into a long-acting formulation (RPV LA) to improve adherence for preexposure prophylaxis (PrEP) to prevent HIV-1 transmission. A concern is that RPV LA will not inhibit transmission of drug-resistant HIV-1 and may select for drug-resistant virus. In female humanized mice, we found that RPV LA inhibited vaginal transmission of WT or 3-fold RPV-resistant HIV-1 but not virus with 30-fold RPV resistance. In animals that became infected despite RPV LA PrEP, WT HIV-1 dissemination was delayed until genital and plasma RPV concentrations waned. RPV resistance was detected at similar low frequencies in untreated and PrEP-treated mice that became infected. These results indicate the importance of maintaining RPV at a sustained threshold after virus exposure to prevent dissemination of HIV-1 after vaginal infection and low-frequency resistance mutations conferred low-level resistance, suggesting that RPV resistance is difficult to develop after HIV-1 infection during RPV LA PrEP.

As a long-acting formulation of the nonnucleoside reverse transcriptase inhibitor rilpivirine (RPV LA) has been proposed for use as preexposure prophylaxis (PrEP) and the prevalence of transmitted RPV-resistant viruses can be relatively high, we evaluated the efficacy of RPV LA to inhibit vaginal transmission of RPV-resistant HIV-1 in humanized mice. Vaginal challenges of wild-type (WT), Y181C, and Y181V HIV-1 were performed in mice left untreated or after RPV PrEP. Plasma viremia was measured for 7 to 10 weeks, and single-genome sequencing was performed on plasma HIV-1 RNA in mice infected during PrEP. RPV LA significantly prevented vaginal transmission of WT HIV-1 and Y181C HIV-1, which is 3-fold resistant to RPV. However, it did not prevent transmission of Y181V HIV-1, which has 30-fold RPV resistance in the viruses used for this study. RPV LA did delay WT HIV-1 dissemination in infected animals until genital and plasma RPV concentrations waned. Animals that became infected despite RPV LA PrEP did not acquire new RPV-resistant mutations above frequencies in untreated mice or untreated people living with HIV-1, and the mutations detected conferred low-level resistance. These data suggest that high, sustained concentrations of RPV were required to inhibit vaginal transmission of HIV-1 with little or no resistance to RPV but could not inhibit virus with high resistance. HIV-1 did not develop high-level or high-frequency RPV resistance in the majority of mice infected after RPV LA treatment. However, the impact of low-frequency RPV resistance on virologic outcome during subsequent antiretroviral therapy still is unclear.

IMPORTANCE The antiretroviral drug rilpivirine was developed into a long-acting formulation (RPV LA) to improve adherence for preexposure prophylaxis (PrEP) to prevent HIV-1 transmission. A concern is that RPV LA will not inhibit transmission of drug-resistant HIV-1 and may select for drug-resistant virus. In female humanized mice, we found that RPV LA inhibited vaginal transmission of WT or 3-fold RPV-resistant HIV-1 but not virus with 30-fold RPV resistance. In animals that became infected despite RPV LA PrEP, WT HIV-1 dissemination was delayed until genital and plasma RPV concentrations waned. RPV resistance was detected at similar low frequencies in untreated and PrEP-treated mice that became infected. These results indicate the importance of maintaining RPV at a sustained threshold after virus exposure to prevent dissemination of HIV-1 after vaginal infection and low-frequency resistance mutations conferred low-level resistance, suggesting that RPV resistance is difficult to develop after HIV-1 infection during RPV LA PrEP.

High rates of antiretroviral coverage and virological suppression in HIV-1-infected children and adolescents

OBJECTIVES

To assess the outcome of HIV-infected individuals attending one of the largest French pediatric HIV centers in 2016-2017 and to compare the rates of antiretroviral coverage and virological suppression with the UNAIDS targets.

PATIENTS AND METHODS

The clinical and immuno-virological status of 163 HIV-1-infected children and adolescents attending Necker Hospital in Paris, France, were investigated. Virological suppression was defined as an HIV-1 viral load<50 copies/mL for at least six months. All genotypic resistance tests performed since birth were analyzed.

RESULTS

Most patients were born in Sub-Saharan African countries (41.7%) or in France (38.0%). Their median age was 14 years [IQR 7.3-17.0]. Although 33.7% of individuals had a history of AIDS-defining clinical event(s), 86.5% of children/adolescents were free from HIV-related symptoms at their most recent evaluation. Antiretroviral coverage was high (98.2%; mainly including one integrase inhibitor [42.3%] or one protease inhibitor [23.9%]). At the last visit, most patients (82.8%) had normal CD4T lymphocytes counts (≥25%). Although 61.7% of antiretroviral-experienced children had resistance to≥1 drug class and 9.2% had triple-class resistance, 80.3% of patients receiving antiretrovirals for≥6 months (126/157) were virologically suppressed. International adoptees were more frequently virologically suppressed than other patients (96.0% versus 74.6%, P=0.02).

CONCLUSIONS

Antiretroviral coverage exceeded the second UNAIDS 90 target aimed at ending the AIDS epidemic. The rate of virological suppression, one of the highest reported in children in high-income countries, is approaching the third UNAIDS 90 target and the rate observed in French HIV-infected adults on antiretrovirals.

Efavirenz is associated with altered fronto-striatal function in HIV+ adolescents

Neurotoxicity associated with the antiretroviral efavirenz (EFV) has been documented in HIV-infected adults, but there are no data on the impact of EFV on brain function in adolescents. We investigated potential alterations in fronto-striatal function associated with EFV use in adolescents. A total of 86 adolescents underwent a Stop Signal Anticipation Task (SSAT) during functional MRI (fMRI), 39 HIV+ adolescents receiving EFV, 27 HIV+ adolescents on antiretroviral therapy without EFV (matched on age, gender, education, CD4 cell count and HIV viral load) and 20 HIV- matched controls (matched on age and gender). The task required participants to give timed GO responses with occasional STOP signals at fixed probabilities. Reactive inhibition was modelled as a correct STOP response and proactive inhibition was modelled after response slowing as the STOP probability increases. A priori mask-based regions associated with reactive and proactive inhibition were entered into two respective multivariate ANOVAs. The EFV treatment group showed significantly blunted proactive inhibitory behavioural responses compared to HIV+ adolescents not receiving EFV. There was no difference in reactive inhibition between treatment groups. We also demonstrated a significant effect of EFV treatment on BOLD signal in proactive inhibition regions. There was no difference in regions involved in reactive inhibition. We found no differences between adolescents not receiving EFV and HIV- controls, showing that functional and behavioural differences were unique to the EFV group. Here, we demonstrate for the first time a potential adverse impact of EFV on higher cortical function in young HIV+ adolescents.

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.