Zidovudine genotypic resistance in HIV-1-infected newborns in the French perinatal cohort

HIV-1 Subtype Diversity and Prevalence of Primary Drug Resistance in a Single-Center Pediatric Cohort in Germany

OBJECTIVES

Data on drug-resistant mutations (DRMs) in HIV-1-infected therapy-naïve children are scarce. The aim of this study was to determine the HIV-1 subtype distribution and the prevalence of DRMs in therapy-naïve HIV-1-infected children who received routine care at the University Hospital Düsseldorf, Düsseldorf, Germany.

METHODS

Records of all HIV-1-infected children who received routine care between January 2005 and December 2015 were analyzed retrospectively. The collected data included demographics, clinical characteristics, CD4 cell count, viral load, HIV-1 subtype, and resistance genotype at baseline.

RESULTS

83 HIV-1-infected children received routine care during the observation period. HIV-1 subtypes were available in 61/83 patients (73.5%) and baseline HIV-1 resistance in 24 (29%). The prevalence of major DRMs was 29% (21% nucleoside reverse-transcriptase inhibitors [NRTIs], 12.5% non-NRTIs, and 4% protease inhibitors). Minor mutations in the protease gene were common (58%). Non-B subtypes were predominant (77%).

CONCLUSIONS

We report a predominance of non-subtype-B infections and a higher prevalence of DRMs compared to other pediatric cohorts from resource-rich settings. The difference in HIV-1 subtype distribution is due to the fact that a relevant proportion of pediatric patients in Germany are immigrants from high-prevalence settings in sub-Saharan Africa where non-B subtypes predominate.

Prevalence and effect of pre-treatment drug resistance on the virological response to antiretroviral treatment initiated in HIV-infected children - a EuroCoord-CHAIN-EPPICC joint project

Background

Few studies have evaluated the impact of pre-treatment drug resistance (PDR) on response to combination antiretroviral treatment (cART) in children. The objective of this joint EuroCoord-CHAIN-EPPICC/PENTA project was to assess the prevalence of PDR mutations and their association with virological outcome in the first year of cART in children.

Methods

HIV-infected children <18 years initiating cART between 1998 and 2008 were included if having at least one genotypic resistance test prior to cART initiation. We used the World Health Organization 2009 resistance mutation list and Stanford algorithm to infer resistance to prescribed drugs. Time to virological failure (VF) was defined as the first of two consecutive HIV-RNA > 500 copies/mL after 6 months cART and was assessed by Cox proportional hazards models. All models were adjusted for baseline demographic, clinical, immunology and virology characteristics and calendar period of cART start and initial cART regimen.

Results

Of 476 children, 88 % were vertically infected. At cART initiation, median (interquartile range) age was 6.6 years (2.1–10.1), CD4 cell count 297 cells/mm³ (98–639), and HIV-RNA 5.2 log₁₀copies/mL (4.7–5.7). Of 37 children (7.8 %, 95 % confidence interval (CI), 5.5–10.6) harboring a virus with ≥1 PDR mutations, 30 children had a virus resistant to ≥1 of the prescribed drugs. Overall, the cumulative Kaplan-Meier estimate for virological failure was 19.8 % (95 %CI, 16.4–23.9). Cumulative risk for VF tended to be higher among children harboring a virus with PDR and resistant to ≥1 drug prescribed than among those receiving fully active cART: 32.1 % (17.2–54.8) versus 19.4 % (15.9–23.6) (P = 0.095). In multivariable analysis, age was associated with a higher risk of VF with a 12 % reduced risk per additional year (HR 0.88; 95 %CI, 0.82–0.95; P < 0.001).

Conclusions

PDR was not significantly associated with a higher risk of VF in children in the first year of cART. The risk of VF decreased by 12 % per additional year at treatment initiation which may be due to fading of PDR mutations over time. Lack of appropriate formulations, in particular for the younger age group, may be an important determinant of virological failure.

Electronic supplementary material

The online version of this article (doi:10.1186/s12879-016-1968-2) contains supplementary material, which is available to authorized users.

HIV-1 drug resistance prevalence, drug susceptibility and variant characterization in the Jacobi Medical Center paediatric cohort, Bronx, NY, USA

OBJECTIVES

With the advent of combined antiretroviral therapy (cART), perinatally HIV-infected children are surviving into adolescence and beyond. However, drug resistance mutations (DRMs) compromise viral control, affecting the long-term effectiveness of ART. The aims of this study were to detect and identify DRMs in a HIV-1 infected paediatric cohort.

METHODS

Paired plasma and dried blood spots (DBSs) specimens were obtained from HIV-1 perinatally infected patients attending the Jacobi Medical Center, New York, USA. Clinical, virological and immunological data for these patients were analysed. HIV-1 pol sequences were generated from samples to identify DRMs according to the International AIDS Society (IAS) 2011 list.

RESULTS

Forty-seven perinatally infected patients were selected, with a median age of 17.7 years, of whom 97.4% were carrying subtype B. They had a mean viral load of 3143 HIV-1 RNA copies/mL and a mean CD4 count of 486 cells/μL at the time of sampling. Nineteen patients (40.4%) had achieved undetectable viraemia (< 50 copies/mL) and 40.5% had a CD4 count of > 500 cells/μL. Most of the patients (97.9%) had received cART, including protease inhibitor (PI)-based regimens in 59.6% of cases. The DRM prevalence was 54.1, 27.6 and 27.0% for nucleoside reverse transcriptase inhibitors (NRTIs), PIs and nonnucleoside reverse transcriptase inhibitors (NNRTIs), respectively. Almost two-thirds (64.9%) of the patients harboured DRMs to at least one drug class and 5.4% were triple resistant. The mean nucleotide similarity between plasma and DBS sequences was 97.9%. Identical DRM profiles were present in 60% of plasma-DBS paired sequences. A total of 30 DRMs were detected in plasma and 26 in DBSs, with 23 present in both.

CONCLUSIONS

Although more perinatally HIV-1-infected children are reaching adulthood as a result of advances in cART, our study cohort presented a high prevalence of resistant viruses, especially viruses resistant to NRTIs. DBS specimens can be used for DRM detection.

HIV drug resistance and mother-to-child transmission of HIV

This article covers HIV drug resistance among pregnant women and the implications of transmission of resistant HIV to the infant. Resistance to antiretroviral drugs may be acquired or can emerge while HIV-infected pregnant women are on antiretroviral therapy, either before or during pregnancy. Resistance to antiretroviral drugs among HIV-infected infants may be acquired from the mother in utero or during the intrapartum period. Resistance may also emerge from exposure to antiretroviral drugs given to the infant for prophylaxis against HIV transmission. In settings where breastfeeding is practiced, ongoing transmission of HIV from breastfeeding may lead to transmission of resistant HIV from the mother. If the mother is taking antiretroviral drugs while breastfeeding, resistance to antiretroviral drugs may emerge in an HIV-infected infant from ingestion of antiretroviral drugs via breast milk. The magnitude and implications of antiretroviral resistance among HIV-infected pregnant women and HIV-infected infants are summarized.

Perinatal acquisition of drug-resistant HIV-1 infection: mechanisms and long-term outcome

Background

Primary-HIV-1-infection in newborns that occurs under antiretroviral prophylaxis that is a high risk of drug-resistance acquisition. We examine the frequency and the mechanisms of resistance acquisition at the time of infection in newborns.

Patients and Methods

We studied HIV-1-infected infants born between 01 January 1997 and 31 December 2004 and enrolled in the ANRS-EPF cohort. HIV-1-RNA and HIV-1-DNA samples obtained perinatally from the newborn and mother were subjected to population-based and clonal analyses of drug resistance. If positive, serial samples were obtained from the child for resistance testing.

Results

Ninety-two HIV-1-infected infants were born during the study period. Samples were obtained from 32 mother-child pairs and from another 28 newborns. Drug resistance was detected in 12 newborns (20%): drug resistance to nucleoside reverse transcriptase inhibitors was seen in 10 cases, non-nucleoside reverse transcriptase inhibitors in two cases, and protease inhibitors in one case. For 9 children, the detection of the same resistance mutations in mothers' samples (6 among 10 available) and in newborn lymphocytes (6/8) suggests that the newborn was initially infected by a drug-resistant strain. Resistance variants were either transmitted from mother-to-child or selected during subsequent temporal exposure under suboptimal perinatal prophylaxis. Follow-up studies of the infants showed that the resistance pattern remained stable over time, regardless of antiretroviral therapy, suggesting the early cellular archiving of resistant viruses. The absence of resistance in the mother of the other three children (3/10) and neonatal lymphocytes (2/8) suggests that the newborns were infected by a wild-type strain without long-term persistence of resistance when suboptimal prophylaxis was stopped.

Conclusion

This study confirms the importance of early resistance genotyping of HIV-1-infected newborns. In most cases (75%), drug resistance was archived in the cellular reservoir and persisted during infancy, with or without antiretroviral treatment. This finding stresses the need for effective antiretroviral treatment of pregnant women.

High frequency of primary mutations associated with antiretroviral drug resistance in recently diagnosed HIV-infected children

Introduction

The aim of our study was to analyse the frequency of primary mutations associated with HIV drug resistance in a population of children born to HIV-infected mothers.

Design

A prospective study included newly HIV-diagnosed children treated at two public paediatric hospitals.

Patients and methods

Clinical and antiretroviral therapy (ART) data were collected in mother-child pairs. HIV-1 subtyping and ART resistance mutations were assayed in children by sequencing a region of HIV pol gene.

Results: A total of 67 children were enrolled

22 less than 12 months of age, 20 between 1 and 5 years and 25 between 6 and 14 years. Six (9.0%) children had viral strains with at least one primary mutation associated with resistance to reverse transcriptase and protease inhibitors. A significantly ( P=0.019) higher frequency of resistance (22.7%, n=5/22) was found among children aged <12 months. Fourteen children (20.9%) had a subtype B HIV-1 strain and 53 (79.1%) had an inter-subtype B/F recombinant variant.

Discussion

A high percentage of recently diagnosed infants were found to carry primary ART resistance mutations. Limited options for ART of HIV-infected children might lead to increased HIV-associated morbidity and mortality. Thus, consideration should be given to mandatory screening for primary ART resistance before initiating therapy for infants aged <12 months in countries where HIV mother-to-child transmission is still present, such as in Argentina. This will allow for the rationalized and individualized use of drugs and will contribute to the increased cost-effectiveness of local health systems.

Prevalence of transmitted HIV-1 drug resistance and the role of resistance algorithms: data from seroconverters in the CASCADE collaboration from 1987 to 2003

OBJECTIVES

To examine factors influencing the rate of transmitted drug resistance (TDR) among seroconverters, with particular emphasis on 3 widely used genotypic drug resistance algorithms.

METHODS

The study used data from CASCADE (Concerted Action on Seroconversion to AIDS and Death in Europe), a collaboration of seroconverter cohorts in Europe and Canada. Genotypic resistance data were derived within 18 months of the last seronegative test or date of laboratory evidence of acute infection and before the initiation of antiretroviral therapy. The Stanford algorithm was used to analyze each individual's nucleotide sequence. A multivariate logistic model was used to assess independent relationships between the presence of TDR and exposure category, sex, age at seroconversion, and year of seroconversion. The paper also describes 3 alternative definitions of resistance: the Stanford algorithm, the key resistance mutations defined by the International AIDS Society, and the Agence Nationale de Recherches sur le Sida (ANRS) algorithm.

RESULTS

Forty-five of 438 patients (10.3%) seroconverting between 1987 and 2003 were infected with a drug-resistant HIV-1 variant. Forty patients (9.1%) showed resistance mutations to only 1 class of antiretroviral drugs, 2 (0.5%) to 2 classes, and 3 (0.7%) to 3 classes of antiretroviral therapy. It was suggested that individuals seroconverting later in calendar time were more likely to have TDR (relative risk 3.89 and 95% CI: 0.84 to 18.02, and relative risk 4.69 and 95% CI: 1.03 to 21.31, for 1996-1999 and 2000-2003, respectively, compared with pre-1996; P trend = 0.08). This trend was apparent regardless of the definition of TDR used. The total estimated proportion of individuals with TDR varied between 10.3% and 15.5% according to which definition was used.

CONCLUSIONS

Evidence was found for the rise of TDR over time. A specific definition of what constitutes TDR rather than a simple list of mutations is needed.

Pharmacokinetics of didanosine and drug resistance mutations in infants exposed to zidovudine during gestation or postnatally and treated with didanosine or zidovudine in the first three months of life

BACKGROUND

There are limited numbers of drugs that are available in formulations that are appropriate for neonates and few studies assessing resistance among infants born to human immunodeficiency virus (HIV)-infected women.

METHODS

Pharmacokinetics and tolerance of didanosine (ddI) were determined for infants < or =120 days of age. Infants received at least 24 hours of zidovudine (ZDV) treatment, followed by a single ddI dose and pharmacokinetic sampling. The target area under the concentration-time curve (AUC) was between 2.5 and 5.0 microM . hour. Toxicity and drug resistance mutations were assessed at baseline and follow-up times.

RESULTS

The initial ddI pharmacokinetic dosing of 50 mg/m for infants >28 days of age achieved a median AUC0-infinity of 2.8 microM . hour. For infants < or =28 days of age, the target AUC was achieved after dose escalation from 25 mg/m (median AUC0-infinity, 1.4 microM . hour) to 50 mg/m (median AUC0-infinity, 5.40 microM . hour). At baseline, 25% of infected infants had drug resistance mutations (9 of 44 to ZDV and 2 of 44 to ddI). Resistance mutations were present for 29% of infants (5 of 17 infants) with in utero ZDV exposure and 25% (8 of 32 infants) with prior ZDV treatment. The most common ZDV mutation noted at baseline was the T215Y/F (n = 7) mutation; 2 of these infants also had the M41L mutation, which is associated with high level ZDV resistance. No prior exposure was noted for the 2 infants with ddI resistance, which indicates possible perinatal transmission of ddI-resistant virus to these infants.

CONCLUSIONS

A dose of 50 mg/m is the appropriate ddI dose for infants <120 days of age and is a safe treatment for newborns when used in combination with ZDV. Genotypic resistance occurs frequently among infected infants exposed to ZDV during gestation or postnatally, which suggests that resistance testing should be considered for infants with newly diagnosed HIV infection.

A pilot study to evaluate the safety and feasibility of the administration of AZT/3TC fixed dose combination to HIV infected pregnant women and their infants in Rio de Janeiro, Brazil

OBJECTIVES

To evaluate the safety and feasibility of zidovudine and lamivudine (AZT/3TC) given to HIV infected pregnant women and their infants in Rio de Janeiro, Brazil.

METHODS

This open label phase II study enrolled 40 HIV infected antiretroviral naive women >or=20 weeks gestation, CD4 <500 cells x10(6)/l, from two public hospitals.

TREATMENT

fixed dose AZT 300 mg/3TC 150 mg by mouth every 12 hours until labour; AZT 300 mg by mouth every 3 hours until delivery; infants: AZT 4 mg/kg every 12 hours plus 3TC 2 mg/kg every 12 hours for 6 weeks. Blood haematology and chemistry were monitored; adherence evaluated by pills count; efficacy measured by changes in lymphocyte (CD4) and viral load, and by HIV RNA-PCR tests performed at birth, 6 and 12 weeks, to diagnose infant infection. No women breast fed.

RESULTS

PATIENT CHARACTERISTICS

mean age 24.48 (SD 3.5) years; gestational age 24.5 (4.5) weeks; AZT/3TC duration 14.4 (4.4) weeks; vaginal delivery: 11/39; caesarean section: 28/39. Entry and pre-labour CD4: 310/486 cells x10(6)/l (p<0.001); entry and pre-labour viral load: 53 818/2616 copies/ml (p<0.001). Thirty nine women tolerated treatment with >80% adherence; one was lost to follow up. Five newborns were excluded from 3TC receipt. All 39 babies were uninfected. Haematological toxicity in newborns was common: anaemia in 27; neutropenia in five (two severe); platelets counts <100000 in two. All values recovered on study completion.

CONCLUSIONS

Fixed dose AZT/3TC is well accepted, gives improvements in CD4 and viral load; no infants were HIV infected. Haematological toxicity in infants needs careful monitoring.

Antiretroviral drug resistance testing in adults infected with human immunodeficiency virus type 1: 2003 recommendations of an International AIDS Society-USA Panel

New information about the benefits and limitations of testing for resistance to human immunodeficiency virus (HIV) type 1 (HIV-1) drugs has emerged. The International AIDS Society-USA convened a panel of physicians and scientists with expertise in antiretroviral drug management, HIV-1 drug resistance, and patient care to provide updated recommendations for HIV-1 resistance testing. Published data and presentations at scientific conferences, as well as strength of the evidence, were considered. Properly used resistance testing can improve virological outcome among HIV-infected individuals. Resistance testing is recommended in cases of acute or recent HIV infection, for certain patients who have been infected as long as 2 years or more prior to initiating therapy, in cases of antiretroviral failure, and during pregnancy. Limitations of resistance testing remain, and more study is needed to refine optimal use and interpretation.