When prevention of mother-to-child HIV transmission fails: preventing pretreatment drug resistance in African children

Prevalence and characteristics of HIV drug resistance among antiretroviral treatment (ART) experienced adolescents and young adults living with HIV in Ndola, Zambia

Background

HIV drug resistance (HIVDR) poses a threat to the HIV epidemic control in Zambia especially in sub-populations such as the 15–24 years where there is poor virological suppression. Understanding the prevalence and patterns of HIVDR in this population (15–24 years) will contribute to defining effective antiretroviral therapy (ART) regimens, improving clinical decision making, and supporting behavioral change interventions needed to achieve HIV epidemic control.

Methods

A cross-sectional analysis of study enrollment data from the Project YES! Youth Engaging for Success randomized controlled trial was conducted. Participants were 15 to 24 years old, who knew their HIV status, and had been on ART for at least 6 months. All participants completed a survey and underwent viral load (VL) testing. Participants with viral failure (VL ≥1,000 copies/mL) underwent HIVDR testing which included analysis of mutations in the protease and reverse transcriptase genes.

Results

A total of 99 out of 273 analyzed participants receiving ART had VL failure, of whom 77 had successful HIVDR amplification and analysis. Out of the 77, 75% (58) had at least one drug resistant mutation, among which 83% (48/58) required a drug change. Among the 58 with HIVDR mutations, the prevalence of at least one HIVDR mutation to nucleoside reverse transcriptase inhibitors (NRTIs), non-nucleoside reverse transcriptase inhibitors (NNRTIs) and protease inhibitors (PIs) were 81%, 65.5% and 1.7%. The mutation M184V which confers resistance to NRTI drugs of lamivudine (3TC) and emtricitabine (FTC) was the most common (81%) among NRTI associated mutations followed by K65R (34.5%) which is associated with both tenofovir disoproxil fumarate (TDF) and tenofovir alafenamide fumarate (TAF) resistance. Thymidine analogue mutations (TAMs) which confer resistance primarily to zidovudine (AZT), stavudine (d4T) and other NRTIs were observed at 32.8%. Common TAMs were K70RTQNE (32.8%), K219QE (22.4%), D67N (17.2%) and T215IT (15.5%). The most common NNRTI associated mutation was the K103N (65.5%) which confers resistance to both efavirenz (EFV) and nevirapine (NVP). There was a relatively high occurrence of other NNRTI mutations V106A (36.2%), as well as Y188C (36.2%) and Y181C (36.2%) which confer resistance to etravirine.

Conclusions

There is a high prevalence of HIVDR including TAMs despite majority of these patients (90.48%) being on AZT or d4T sparing first line ART among the youth. Emergence of these mutations including the NNRTI associated mutations (Y181C and Y188C) may compromise future second- and third-line regimens in the absence of routine HIVDR testing. HIVDR monitoring at start of ART or at first-line failure can better inform clinical decision making and ART programing.

Prevalence and Correlates of Pre-Treatment HIV Drug Resistance among HIV-Infected Children in Ethiopia

Pediatric human immunodeficiency virus (HIV) care in resource-limited settings remains a major challenge to achieving global HIV treatment and virologic suppression targets, in part because the administration of combination antiretroviral therapies (cART) is inherently complex in this population and because viral load and drug resistance genotyping are not routinely available in these settings. Children may also be at elevated risk of transmission of drug-resistant HIV as a result of suboptimal antiretroviral administration for prevention of mother-to-child transmission. We investigated the prevalence and the correlates of pretreatment HIV drug resistance (PDR) among HIV-infected, cART-naive children in Ethiopia. We observed an overall PDR rate of 14%, where all cases featured resistance to non-nucleoside reverse transcriptase inhibitors (NNRTIs): ~9% of participants harbored resistance solely to NNRTIs while ~5% harbored resistance to both NNRTIs and nucleoside reverse transcriptase inhibitors (NRTIs). No resistance to protease inhibitors was observed. No sociodemographic or clinical parameters were significantly associated with PDR, though limited statistical power is noted. The relatively high (14%) rate of NNRTI resistance in cART-naive children supports the use of non-NNRTI-based regimens in first-line pediatric treatment in Ethiopia and underscores the urgent need for access to additional antiretroviral classes in resource-limited settings.

Pretreatment HIV drug resistance in low- and middle-income countries

Pretreatment HIV drug resistance (PDR) has been increasing with scale-up of antiretroviral therapy (ART) in low- and middle-income countries. Delay in responding to rising levels of PDR is projected to fuel a worldwide increase in mortality, HIV incidence and ART costs. Strategies to curb the rise in PDR include using antiretrovirals (ARVs) with high-genetic barrier to resistance in first-line therapy and for prophylaxis in HIV exposed infants, enhancing HIV drug resistance surveillance in populations initiating, receiving ART, and in those on pre-exposure prophylaxis, universal access and effective use of viral-load tests, improving adherence and retention and minimizing ART programmatic quality gaps. In this review, we assess the drivers of PDR, and potential strategies to mitigate its rise in prevalence and impact in low- and middle-income countries.

High Levels of HIV-1 Drug Resistance in Children Who Acquired HIV Infection Through Mother to Child Transmission in the Era of Option B+, Haiti, 2013 to 2014

BACKGROUND

The main objective of this study was to determine the frequency and patterns of HIV drug resistance-associated mutations among children under 18 months of age born to HIV-1-positive mothers enrolled in the prevention of mother-to-child transmission services in Haiti.

METHODS

Between January 1, 2013 and December 31, 2014, HIV-positive remnant dried blood spots collected from children under 18 months of age for Early Infant Diagnosis at the National Public Health Laboratory were used for HIV-1 genotyping. HIV drug resistance mutations were analyzed using the Stanford Drug Resistance HIVdb program.

RESULTS

Of the 3555 dried blood spots collected for Early Infant Diagnosis, 360 (10.1%) were HIV-positive and 355 were available for genotyping. Of these, 304 (85.6%) were successfully genotyped and 217 (71.4%) had ≥1 drug resistance mutation. Mutations conferring resistance to nucleoside reverse transcriptase inhibitor (NRTIs) and non-NRTIs were present in 40.5% (123) and 69.1% (210), respectively. The most frequent mutations were K103N/S (48.0%), M184V (37.5%), G190A/S (15.1%), and Y181C/G/V (14.1%). Predicted drug resistance analysis revealed that 68.8% of the children had high-level resistance to non-NRTIs and 11.5% had intermediate to high-level resistance to abacavir.

CONCLUSIONS

This study showed high rates of resistance to NRTIs and non-NRTIs among newly HIV-diagnosed children in Haiti, suggesting that in the era of "Option B+" (initiation of lifelong combination antiretroviral therapy to pregnant women with HIV), the majority of children who acquire HIV infection through mother-to-child transmission of HIV have resistant HIV. These results have led the National HIV Program to revise the pediatric guidelines to include protease inhibitors in first-line regimens for all HIV-positive newborns.