Initial response to protease-inhibitor-based antiretroviral therapy among children less than 2 years of age in South Africa: effect of cotreatment for tuberculosis

Clinical Outcomes in Children With Human Immunodeficiency Virus Treated for Nonsevere Tuberculosis in the SHINE Trial

BACKGROUND

Children with human immunodeficiency virus (HIV, CWH) are at high risk of tuberculosis (TB) and face poor outcomes, despite antiretroviral therapy (ART). We evaluated outcomes in CWH and children not living with HIV treated for nonsevere TB in the SHINE trial.

METHODS

SHINE was a randomized trial that enrolled children aged <16 years with smear-negative, nonsevere TB who were randomized to receive 4 versus 6 months of TB treatment and followed for 72 weeks. We assessed TB relapse/recurrence, mortality, hospitalizations, grade ≥3 adverse events by HIV status, and HIV virological suppression in CWH.

RESULTS

Of 1204 children enrolled, 127 (11%) were CWH, of similar age (median, 3.6 years; interquartile range, 1.2, 10.3 versus 3.5 years; 1.5, 6.9; P = .07) but more underweight (weight-for-age z score, -2.3; (3.3, -0.8 versus -1.0; -1.8, -0.2; P < .01) and anemic (hemoglobin, 9.5 g/dL; 8.7, 10.9 versus 11.5 g/dL; 10.4, 12.3; P < .01) compared with children without HIV. A total of 68 (54%) CWH were ART-naive; baseline median CD4 count was 719 cells/mm3 (241-1134), and CD4% was 16% (10-26). CWH were more likely to be hospitalized (adjusted odds ratio, 2.4; 1.3-4.6) and to die (adjusted hazard ratio [aHR], 2.6; 95% confidence interval [CI], 1.2 to 5.8). HIV status, age <3 years (aHR, 6.3; 1.5, 27.3), malnutrition (aHR, 6.2; 2.4, 15.9), and hemoglobin <7 g/dL (aHR, 3.8; 1.3,11.5) independently predicted mortality. Among children with available viral load (VL), 45% and 61% CWH had VL <1000 copies/mL at weeks 24 and 48, respectively. There was no difference in the effect of randomized treatment duration (4 versus 6 months) on TB treatment outcomes by HIV status (P for interaction = 0.42).

CONCLUSIONS

We found no evidence of a difference in TB outcomes between 4 and 6 months of treatment for CWH treated for nonsevere TB. Irrespective of TB treatment duration, CWH had higher rates of mortality and hospitalization than their counterparts without HIV. Clinical Trials Registration. ISRCTN63579542.

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.

FCGR3A gene duplication, FcγRIIb-232TT and FcγRIIIb-HNA1a associate with an increased risk of vertical acquisition of HIV-1

Background

Some mother-to-child transmission (MTCT) studies suggest that allelic variations of Fc gamma receptors (FcγR) play a role in infant HIV-1 acquisition, but findings are inconsistent. To address the limitations of previous studies, the present study investigates the association between perinatal HIV-1 transmission and FcγR variability in three cohorts of South African infants born to women living with HIV-1.

Methods

This nested case-control study combines FCGR genotypic data from three perinatal cohorts at two hospitals in Johannesburg, South Africa. Children with perinatally-acquired HIV-1 (cases, n = 395) were compared to HIV-1-exposed uninfected children (controls, n = 312). All study participants were black South Africans and received nevirapine for prevention of MTCT. Functional variants were genotyped using a multiplex ligation-dependent probe amplification assay, and their representation compared between groups using logistic regression analyses.

Results

FCGR3A gene duplication associated with HIV-1 acquisition (OR = 10.27; 95% CI 2.00–52.65; P = 0.005) as did the FcγRIIb-232TT genotype even after adjusting for FCGR3A copy number and FCGR3B genotype (AOR = 1.72; 95%CI 1.07–2.76; P = 0.024). The association between FcγRIIb-232TT genotype and HIV-1 acquisition was further strengthened (AOR = 2.28; 95%CI 1.11–4.69; P = 0.024) if adjusted separately for FCGR2C c.134-96C>T. Homozygous FcγRIIIb-HNA1a did not significantly associate with HIV-1 acquisition in a univariate model (OR = 1.42; 95%CI 0.94–2.16; P = 0.098) but attained significance after adjustment for FCGR3A copy number and FCGR2B genotype (AOR = 1.55; 95%CI 1.01–2.38; P = 0.044). Both FcγRIIb-232TT (AOR = 1.83; 95%CI 1.13–2.97; P = 0.014) and homozygous FcγRIIIb-HNA1a (AOR = 1.66; 95%CI 1.07–2.57; P = 0.025) retained significance when birthweight and breastfeeding were added to the model. The common FCGR2A and FCGR3A polymorphisms did not associate with HIV-1 acquisition.

Conclusions

Collectively, our findings suggest that the FcγRIIb-232TT genotype exerts a controlling influence on infant susceptibility to HIV-1 infection. We also show a role for less studied variants–FCGR3A duplication and homozygous HNA1a. These findings provide additional insight into a role for FcγRs in HIV-1 infection in children.

An HIV Vaccine Protective Allele in FCGR2C Associates With Increased Odds of Perinatal HIV Acquisition

In the Thai RV144 HIV-1 vaccine trial, a three-variant haplotype within the Fc gamma receptor 2C gene (FCGR2C) reduced the risk of HIV-1 acquisition. A follow-on trial, HVTN702, of a similar vaccine candidate found no efficacy in South Africa, where the predominant population is polymorphic for only a single variant in the haplotype, c.134-96C>T (rs114945036). To investigate a role for this variant in HIV-1 acquisition in South Africans, we used the model of maternal-infant HIV-1 transmission. A nested case-control study was conducted of infants born to mothers living with HIV-1, comparing children with perinatally-acquired HIV-1 (cases, n = 176) to HIV-1-exposed uninfected children (controls, n = 349). All had received nevirapine for prevention of mother-to-child transmission. The FCGR2C copy number and expression variants (c.-386G>C, c.-120A>T c.169T>C, and c.798+1A>G) were determined using a multiplex ligation-dependent probe amplification assay and the c.134-96C>T genotype with Sanger sequencing. The copy number, genotype and allele carriage were compared between groups using univariate and multivariate logistic regression. The FCGR2C c.134-96C>T genotype distribution and copy number differed significantly between HIV-1 cases and exposed-uninfected controls (P = 0.002, P _Bonf = 0.032 and P = 0.010, P _Bonf = > 0.05, respectively). The FCGR2C c.134-96T allele was overrepresented in the cases compared to the controls (58% vs 42%; P = 0.001, P _Bonf = 0.016). Adjusting for birthweight and FCGR2C copy number, perinatal HIV-1 acquisition was associated with the c.134-96C>T (AOR = 1.89; 95% CI 1.25-2.87; P = 0.003, P _Bonf = 0.048) and c.169C>T (AOR = 2.39; 95% CI 1.45-3.95; P = 0.001, P _Bonf = 0.016) minor alleles but not the promoter variant at position c.-386G>C. The c.134-96C>T variant was in strong linkage disequilibrium with the c.169C>T variant, but remained significantly associated with perinatal acquisition when adjusted for c.169C>T in multivariate analysis. In contrast to the protective effect observed in the Thai RV144 trial, we found the FCGR2C variant c.134-96T-allele associated with increased odds of perinatal HIV-1 acquisition in South African children. These findings, taken together with a similar deleterious association found with HIV-1 disease progression in South African adults, highlight the importance of elucidating the functional relevance of this variant in different populations and vaccination/disease contexts.

Drug Resistance Mutations Among South African Children Living With HIV on WHO-recommended ART Regimens

BACKGROUND

Children living with human immunodeficiency virus (HIV) (CLHIV) receiving antiretroviral therapy (ART) in resource-limited settings are susceptible to high rates of acquired HIV drug resistance (HIVDR), but few studies include children initiating age-appropriate World Health Organization (WHO)-recommended first-line regimens. We report data from a cohort of ART-naive South African children who initiated first-line ART.

METHODS

ART-eligible CLHIV aged 0-12 years were enrolled from 2012 to 2014 at 5 public South African facilities and were followed for up to 24 months. Enrolled CLHIV received standard-of-care WHO-recommended first-line ART. At the final study visit, a dried blood spot sample was obtained for viral load and genotypic resistance testing.

RESULTS

Among 72 successfully genotyped CLHIV, 49 (68.1%) received ABC/3TC/LPV/r, and 23 (31.9%) received ABC/3TC/EFV. All but 2 children on ABC/3TC/LPV/r were <3 years, and all CLHIV on ABC/3TC/EFV were ≥3 years. Overall, 80.6% (58/72) had at least one drug resistance mutation (DRM). DRMs to nonnucleoside reverse transcriptase inhibitors (NNRTIs) and nucleoside reverse transcriptase inhibitors (NRTIs) were found among 65% and 51% of all CLHIV, respectively, with no statistical difference by ART regimen. More CLHIV on ABC/3TC/EFV, 47.8% (11/23), were found to have 0 or only 1 effective antiretroviral drug remaining in their current regimen compared to 8.2% (4/49) on ABC/3TC/LPV/r.

CONCLUSIONS

High levels of NNRTI and NRTI DRMs among CLHIV receiving ABC/3TC/LPV/r suggests a lasting impact of failed mother-to-child transmission interventions on DRMs. However, drug susceptibility analysis reveals that CLHIV with detectable viremia on ABC/3TC/LPV/r are more likely to have maintained at least 2 effective agents on their current HIV regimen than those on ABC/3TC/EFV.

Low Pretreatment Viral Loads in Infants With HIV in an Era of High-maternal Antiretroviral Therapy Coverage

BACKGROUND

With expansion of antiretroviral therapy (ART) programs, transmission rates are low but new infant infections still occur. We investigated predictors of pre-ART viral load (VL) and CD4+ T-cell counts and percentages in infants diagnosed with HIV at birth in a setting with high coverage of maternal ART and infant prophylaxis.

METHODS

As part of an early treatment study, 97 infants with confirmed HIV-infection were identified at a hospital in Johannesburg, South Africa. Infant VL and CD4+ T-cell parameters were measured before ART initiation. Data were collected on maternal characteristics, including VL, CD4+ T-cell counts and ART, and infant characteristics, including sex, birth weight, and mode of delivery.

RESULTS

Pre-ART, median infant VL was 28,405 copies/mL [interquartile range (IQR): 2515-218,150], CD4+ T-cell count 1914 cells/mm (IQR: 1474-2639) and percentage 40.8% (IQR: 32.2-51.2). Most (80.4%) infants were born to mothers who received ART during pregnancy and 97.9% of infants received daily nevirapine prophylaxis until ART initiation at median of 2 days of age (IQR: 1-7). Infant pre-ART VL was more likely to be ≥1000 copies/mL when their mothers had VL ≥1000 copies/mL [Odds Ratio (OR): 6.88, 95% confidence interval (CI): 2.32-20.41] and was higher in boys than girls (OR: 3.29, 95% CI: 1.07-9.95). Lower maternal CD4+ T-cell count (<350 cells/mm) was associated with lower infant CD4+ T-cell count (<1500 cells/mm) (OR: 3.59, 95% CI: 1.24-10.43).

CONCLUSIONS

Pre-ART VL and CD4+ T-cell parameters of intrauterine-infected infants were associated with VL and CD4+ T-cell counts of their mothers. Maternal ART during pregnancy may begin treatment of intrauterine infection and may mask the severity of disease in infected infants identified in the current era with high-maternal ART coverage.

12-month outcomes of HIV-infected infants identified at birth at one maternity site in Johannesburg, South Africa: an observational cohort study

BACKGROUND

Initiation of antiretroviral therapy (ART) following diagnosis of HIV infection at birth is an emerging area of paediatric HIV care. We present outcomes of HIV-infected infants identified at birth at Rahima Moosa Mother and Child Hospital in Johannesburg, South Africa.

METHODS

From September, 2013 (era 1), only high-risk HIV-exposed infants were offered diagnostic HIV PCR tests at birth. From June, 2014 (era 2), all HIV-exposed infants were offered laboratory-based diagnostic PCR tests. From October, 2014 (era 3), point of care (POC) diagnostic PCR tests were also done if staff availability allowed. We describe time to ART initiation, mortality, retention in care, and viral suppression among the HIV-infected infants identified across these eras.

FINDINGS

We tested 5449 HIV-exposed infants who were born between Sept 1, 2013, and June 30, 2016. 88 neonates with confirmed HIV infection were identified and included in the study, of which 86 (98%) started ART. Median age at ART initiation decreased from 9 days (IQR 6-25) in eras 1 and 2 to 2 days (1-8) in era 3. In era 3, more neonates who were co-tested with POC testing started ART within 48 h of birth (29 [83%] of 35; median 1 day [IQR 1-2]) than infants who were not co-tested (one [4%] of 29; median 6 days [5-10]). The probability of mortality by 12 months across the eras was 14% (95% CI 8-24) and did not differ by era. Of the 72 infants who survived and initiated ART at the site, 56 (78%) were retained at 12 months. Of the 56 infants retained in care, 40 (71%) had a viral load less than 400 copies per mL at 12 months, with no differences between eras (p=0·23).

INTERPRETATION

HIV-infected infants can be identified at birth and ART can be initiated within hours to days. Although most infants in our cohort started ART, mortality remained unacceptably high with suboptimal retention and viral suppression. Reducing mortality and improving retention and viral suppression remain urgent priorities.

FUNDING

Eunice Kennedy Shriver National Institute of Child Health and Human Development/National Institute of Allergy and Infectious Disease, National Institutes of Health, USAID/PEPfAR, and the South African National HIV Programme.

Antiretroviral Therapy in HIV-Infected Children With Tuberculosis: A Systematic Review

BACKGROUND

Tuberculosis (TB) is the major cause of mortality in HIV-infected children globally. Current guidelines about the management of antiretroviral therapy in children with TB are based on a limited number of nonrandomized studies involving small numbers of participants. The aim of the study was to systematically retrieve and critically appraise available evidence on the efficacy and safety of different antiretroviral regimens in children with HIV infection who are receiving treatment for active TB.

METHODS

We conducted a systematic review of the literature according to Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines. Records were retrieved through March 2016 from Medline, Embase and manual screening of key conference proceedings. Four specific research questions assessing available treatment options were defined.

RESULTS

Although 4 independent searches were conducted (1 for each Population, Intervention, Comparator, Outcomes question), results were elaborated and interpreted together because of significant overlap among the retrieved records. Six observational studies were selected for qualitative synthesis while meta-analysis could not be performed.

CONCLUSION

Evidence for optimal treatment options for HIV/TB coinfected children is limited. As the global community strives to reach the fast-track HIV treatment targets and eliminate childhood TB deaths, it must ensure that coinfected children are included in key treatment studies and expand this neglected but crucial area of research.

Early antiretroviral therapy in HIV-infected infants: can it lead to HIV remission?

Interventions to prevent mother-to-child HIV transmission have been extremely successful, but new HIV infections continue to occur in infants. Strong evidence indicates that combination antiretroviral therapy (ART) for treatment should be started in HIV-infected infants to prevent early morbidity and mortality. In 2013, the report of the Mississippi baby, who was started on ART within 30 h of life and maintained off-treatment remission for 27 months before HIV was once again detectable, generated renewed interest in very early ART initiation. The case stimulated interest in the possibility of HIV remission, which we define as maintenance of plasma viraemia below the threshold of detection in the absence of ART, after early treatment initiation. The possibility of HIV remission elicits much hope, given that children with HIV infection currently face a lifetime of treatment. The potential for early ART to lead to HIV remission in infants can be thought of in terms of six factors: rapidity of viral suppression with very early ART; initial viral suppression rate with early ART; later virological control after early treatment; the effect of early treatment on the viral reservoir size; outcomes of randomised trials of structured treatment interruption; and the likelihood of viral rebound in neonates after ART cessation. Review of existing data suggests that achieving long-term remission off treatment remains elusive, and concentrated attention and commitment of the scientific community is needed to investigate the factors that might help to reach this goal.

Virological response and resistances over 12 months among HIV-infected children less than two years receiving first-line lopinavir/ritonavir-based antiretroviral therapy in Cote d'Ivoire and Burkina Faso: the MONOD ANRS 12206 cohort

Introduction: Lopinavir/ritonavir-based antiretroviral therapy (ART) is recommended for all HIV-infected children less than three years. However, little is known about its field implementation and effectiveness in West Africa. We assessed the 12-month response to lopinavir/ritonavir-based antiretroviral therapy in a cohort of West African children treated before the age of two years.

Methods: HIV-1-infected, ART-naive except for a prevention of mother-to-child transmission (PMTCT), tuberculosis-free, and less than two years of age children with parent’s consent were enrolled in a 12-month prospective therapeutic cohort with lopinavir/ritonavir ART and cotrimoxazole prophylaxis in Ouagadougou and Abidjan. Virological suppression (VS) at 12 months (viral load [VL] <500 copies/mL) and its correlates were assessed.

Results: Between May 2011 and January 2013, 156 children initiated ART at a median age of 13.9 months (interquartile range: 7.8–18.4); 63% were from Abidjan; 53% were girls; 37% were not exposed to any PMTCT intervention or maternal ART; mother was the main caregiver in 81%; 61% were classified World Health Organization Stage 3 to 4. After 12 months on ART, 11 children had died (7%), 5 were lost-to-follow-up/withdrew (3%), and VS was achieved in 109: 70% of children enrolled and 78% of those followed-up. When adjusting for country and gender, the access to tap water at home versus none (adjusted odds ratio (aOR): 2.75, 95% confidence interval (CI): 1.09–6.94), the mother as the main caregiver versus the father (aOR: 2.82, 95% CI: 1.03–7.71), and the increase of CD4 percentage greater than 10% between inclusion and 6 months versus <10% (aOR: 2.55, 95% CI: 1.05–6.18) were significantly associated with a higher rate of VS. At 12 months, 28 out of 29 children with VL ≥1000 copies/mL had a resistance genotype test: 21 (75%) had ≥1 antiretroviral (ARV) resistance (61% to lamivudine, 29% to efavirenz, and 4% to zidovudine and lopinavir/ritonavir), of which 11 (52%) existed before ART initiation.

Conclusions: Twelve-month VS rate on lopinavir/ritonavir-based ART was high, comparable to those in Africa or high-income countries. The father as the main child caregiver and lack of access to tap water are risk factors for viral failure and justify a special caution to improve adherence in these easy-to-identify situations before ART initiation. Public health challenges remain to optimize outcomes in children with earlier ART initiation in West Africa.

Challenges and perspectives of compliance with pediatric antiretroviral therapy in Sub-Saharan Africa

More than 3 million children aged less than 15years are infected with HIV worldwide, mainly in Sub-Saharan Africa. The survival of HIV-infected children depends on their access to antiretroviral therapy whose success mainly depends on a good life-long compliance with antiretroviral therapy. Given its complexity and specificity, assessment and monitoring of pediatric compliance with antiretroviral therapy is a major challenge. There is no consensus on a gold standard for monitoring compliance with antiretroviral therapy. Compliance is also influenced by many factors related to the child, the caregiver, the healthcare staff, the healthcare system, and antiretroviral drugs. This review aimed to assess scientific knowledge on pediatric compliance with antiretroviral therapy in Sub-Saharan Africa, and to identify areas for future interventions to improve compliance. Good compliance is essential to achieve the "90% coverage of children on antiretroviral therapy" gold standard of the World Health Organization, and to eliminate HIV infection by 2030.

Antiretroviral treatment in HIV-infected children who require a rifamycin-containing regimen for tuberculosis

INTRODUCTION

In high prevalence settings, tuberculosis and HIV dual infection and co-treatment is frequent. Rifamycins, especially rifampicin, in combination with isoniazid, ethambutol and pyrazinamide are key components of short-course antituberculosis therapy. Areas covered: We reviewed available data, for which articles were identified by a Pubmed search, on rifamycin-antiretroviral interactions in HIV-infected children. Rifamycins have potent inducing effects on phase I and II drug metabolising enzymes and transporters. Antiretroviral medications are often metabolised by the enzymes induced by rifamycins or may suppress specific enzyme activity leading to drug-drug interactions with rifamycins. These may cause significant alterations in their phamacokinetic and pharmacodynamic properties, and sometimes that of the rifamycin. Recommended strategies to adapt to these interactions include avoidance and dose adjustment. Expert opinion: Despite the importance and frequency of tuberculosis as an opportunistic disease in HIV-infected children, current data on the management of co-treated children is based on few studies. We need new strategies to rapidly assess the use of rifamycins, new anti-tuberculosis drugs and antiretroviral drugs together as information on safety and dosing of individual drugs becomes available.

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.

Early age at start of antiretroviral therapy associated with better virologic control after initial suppression in HIV-infected infants

OBJECTIVE

The report of the 'Mississippi baby' who was initiated on antiretroviral therapy (ART) within 30 h of birth and maintained viral suppression off ART for 27 months has increased interest in the timing of ART initiation early in life. We examined associations between age at ART initiation and virologic outcomes in five cohorts of HIV-infected infants and young children who initiated ART before 2 years of age in Johannesburg, South Africa.

METHODS

We compared those who initiated ART early (<6 months of age) and those who started ART late (6-24 months of age). Two primary outcomes were examined: initial response to ART in three cohorts and later sustained virologic control after achieving suppression on ART in two cohorts.

RESULTS

We did not observe consistent differences in initial viral suppression rates by age at ART initiation. Overall, initial viral suppression rates were low. Only 31, 40.1, and 26.5% of early-treated infants (<6 months of age) in the three cohorts, respectively, were suppressed less than 50 copies/ml of HIV RNA 6 months after starting ART. We did observe better sustained virologic control after achieving suppression on ART among infants starting ART early compared with late. Children who started ART early were less likely to experience viral rebound (>50 copies/ml or >1000 copies/ml) than children who started late in both cohorts.

CONCLUSION

These findings provide additional support for early initiation of ART in HIV-infected infants.

Tuberculosis and pneumonia in HIV-infected children: an overview

Pneumonia remains the most common cause of hospitalization and the most important cause of death in young children. In high human immunodeficiency virus (HIV)-burden settings, HIV-infected children carry a high burden of lower respiratory tract infection from common respiratory viruses, bacteria and Mycobacterium tuberculosis. In addition, Pneumocystis jirovecii and cytomegalovirus are important opportunistic pathogens. As the vertical transmission risk of HIV decreases and access to antiretroviral therapy increases, the epidemiology of these infections is changing, but HIV-infected infants and children still carry a disproportionate burden of these infections. There is also increasing recognition of the impact of in utero exposure to HIV on the general health of exposed but uninfected infants. The reasons for this increased risk are not limited to socioeconomic status or adverse environmental conditions—there is emerging evidence that these HIV-exposed but uninfected infants may have particular immune deficits that could increase their vulnerability to respiratory pathogens. We discuss the impact of tuberculosis and other lower respiratory tract infections on the health of HIV-infected infants and children.

Contribution of Gag and Protease to HIV-1 Phenotypic Drug Resistance in Pediatric Patients Failing Protease Inhibitor-Based Therapy

Protease inhibitors (PIs) are used as a first-line regimen in HIV-1-infected children. Here we investigated the phenotypic consequences of amino acid changes in Gag and protease on lopinavir (LPV) and ritonavir (RTV) susceptibility among pediatric patients failing PI therapy. The Gag-protease from isolates from 20 HIV-1 subtype C-infected pediatric patients failing an LPV and/or RTV-based regimen was phenotyped using a nonreplicativein vitroassay. Changes in sensitivity to LPV and RTV relative to that of the matched baseline (pretherapy) sample were calculated. Gag and protease amino acid substitutions associated with PI failure were created in a reference clone by site-directed mutagenesis and assessed. Predicted phenotypes were determined using the Stanford drug resistance algorithm. Phenotypic resistance or reduced susceptibility to RTV and/or LPV was observed in isolates from 10 (50%) patients, all of whom had been treated with RTV. In most cases, this was associated with protease resistance mutations, but substitutions at Gag cleavage and noncleavage sites were also detected. Gag amino acid substitutions were also found in isolates from three patients with reduced drug susceptibilities who had wild-type protease. Site-directed mutagenesis confirmed that some amino acid changes in Gag contributed to PI resistance but only in the presence of major protease resistance-associated substitutions. The isolates from all patients who received LPV exclusively were phenotypically susceptible. Baseline isolates from the 20 patients showed a large (47-fold) range in the 50% effective concentration of LPV, which accounted for most of the discordance seen between the experimentally determined and the predicted phenotypes. Overall, the inclusion of thegaggene and the use of matched baseline samples provided a more comprehensive assessment of the effect of PI-induced amino acid changes on PI resistance. The lack of phenotypic resistance to LPV supports the continued use of this drug in pediatric patients.

Missed opportunities of inclusion in a cohort of HIV-infected children to initiate antiretroviral treatment before the age of two in West Africa, 2011 to 2013

INTRODUCTION

The World Health Organization (WHO) 2010 guidelines recommended to treat all HIV-infected children less than two years of age. We described the inclusion process and its correlates of HIV-infected children initiated on early antiretroviral therapy (EART) at less than two years of age in Abidjan, Côte d'Ivoire, and Ouagadougou, Burkina Faso.

METHODS

All children with HIV-1 infection confirmed with a DNA PCR test of a blood sample, aged less than two years, living at a distance less than two hours from the centres and whose parents (or mother if she was the only legal guardian or the legal caregiver if parents were not alive) agreed to participate in the MONOD ANRS 12206 project were included in a cohort to receive EART based on lopinavir/r. We used logistic regression to identify correlates of inclusion.

RESULTS

Among the 217 children screened and referred to the MONOD centres, 161 (74%) were included and initiated on EART. The main reasons of non-inclusion were fear of father's refusal (48%), mortality (24%), false-positive HIV infection test (16%) and other ineligibility reasons (12%). Having previously disclosed the child's and mother's HIV status to the father (adjusted odds ratio (aOR): 3.20; 95% confidence interval (95% CI): 1.55 to 6.69) and being older than 12 months (aOR: 2.05; 95% CI: 1.02 to 4.12) were correlates of EART initiation. At EART initiation, the median age was 13.5 months, 70% had reached WHO Stage 3/4 and 57% had a severe immune deficiency.

CONCLUSIONS

Fear of stigmatization by the father and early competing mortality were the major reasons for missed opportunities of EART initiation. There is an urgent need to involve fathers in the care of their HIV-exposed children and to promote early infant diagnosis to improve their future access to EART and survival.

Tuberculosis: opportunities and challenges for the 90-90-90 targets in HIV-infected children

INTRODUCTION

In 2014 the Joint United Nations Programme on HIV/AIDS defined the ambitious 90-90-90 targets for 2020, in which 90% of people living with HIV must be diagnosed, 90% of those diagnosed should be on sustained therapy and 90% of those on therapy should have an undetectable viral load. Children are considered to be a key focus population for these targets. This review will highlight key components of the epidemiology, prevention and treatment of tuberculosis (TB) in HIV-infected children in the era of increasing access to antiretroviral therapy (ART) and their relation to the 90-90-90 targets.

DISCUSSION

The majority of HIV-infected children live in countries with a high burden of TB. In settings with a high burden of both diseases such as in sub-Saharan Africa, up to 57% of children diagnosed with and treated for TB are HIV-infected. TB results in substantial morbidity and mortality in HIV-infected children, so preventing TB and optimizing its treatment in HIV-infected children will be important to ensuring good long-term outcomes. Prevention of TB can be achieved by increasing access to ART to both children and adults, and appropriate provision of isoniazid preventative therapy. Co-treatment of HIV and TB is complicated by drug-drug interactions particularly due to the use of rifampicin; these may compromise virologic outcomes if appropriate corrective actions are not taken. There remain substantial operational challenges, and improved integration of paediatric TB and HIV services, including with antenatal and routine under-five care, is an important priority.

CONCLUSIONS

TB may be an important barrier to achievement of the 90-90-90 targets, but specific attention to TB care in HIV-infected children may provide important opportunities to enhance the care of both TB and HIV in children.

Recommendations Concerning the Therapeutic Approach to Immunocompromised Children With Tuberculosis

PURPOSE

This article describes the recommendations of a group of scientific societies concerning the therapeutic approach to immunocompromised children with tuberculosis (TB).

METHODS

Using the Consensus Conference method, relevant publications in English were identified by a systematic review of MEDLINE and the Cochrane Database of Systematic Reviews from their inception until December 31, 2014.

FINDINGS

On the basis of their clinical experience and the published evidence, the group of experts concluded that, although immunosuppressed subjects are at greater risk of developing TB, none of the signs or symptoms is sensitive or specific enough to enable a diagnosis. Immunocompromised patients are at greater risk of developing extrapulmonary forms of TB, especially if they are adolescents, whereas pulmonary forms are more prevalent among younger patients. When TB is suspected, a combination of skin and immunologic tests and other clinical, radiologic, and microbiologic examinations can be used to assess the risk of infection or disease. If the TB diagnosis is confirmed, immunocompromised children should be treated by using a standard regimen with a minimum of 4 drugs for at least 9 to 12 months, during which the tolerability of the drugs and their interactions should be carefully evaluated.

IMPLICATIONS

It is difficult to diagnose and treat TB in immunocompromised children. Thus, all pediatric patients undergoing immunosuppressive therapy who develop TB should be diagnosed and treated at a TB reference center, which should also be responsible for the recommended follow-up.

Efavirenz-Based Antiretroviral Therapy Among Nevirapine-Exposed HIV-Infected Children in South Africa: A Randomized Clinical Trial

IMPORTANCE

Advantages of using efavirenz as part of treatment for children infected with human immunodeficiency virus (HIV) include once-daily dosing, simplification of co-treatment for tuberculosis, preservation of ritonavir-boosted lopinavir for second-line treatment, and harmonization of adult and pediatric treatment regimens. However, there have been concerns about possible reduced viral efficacy of efavirenz in children exposed to nevirapine for prevention of mother-to-child transmission.

OBJECTIVE

To evaluate whether nevirapine-exposed children achieving initial viral suppression with ritonavir-boosted lopinavir-based therapy can transition to efavirenz-based therapy without risk of viral failure.

DESIGN, SETTING, AND PARTICIPANTS

Randomized, open-label noninferiority trial conducted at Rahima Moosa Mother and Child Hospital, Johannesburg, South Africa, from June 2010 to December 2013, enrolling 300 HIV-infected children exposed to nevirapine for prevention of mother-to-child transmission who were aged 3 years or older and had plasma HIV RNA of less than 50 copies/mL during ritonavir-boosted lopinavir-based therapy; 298 were randomized and 292 (98%) were followed up to 48 weeks after randomization.

INTERVENTIONS

Participants were randomly assigned to switch to efavirenz-based therapy (n = 150) or continue ritonavir-boosted lopinavir-based therapy (n = 148).

MAIN OUTCOMES AND MEASURES

Risk difference between groups in (1) viral rebound (ie, ≥1 HIV RNA measurement of >50 copies/mL) and (2) viral failure (ie, confirmed HIV RNA >1000 copies/mL) with a noninferiority bound of -0.10. Immunologic and clinical responses were secondary end points.

RESULTS

The Kaplan-Meier probability of viral rebound by 48 weeks was 0.176 (n = 26) in the efavirenz group and 0.284 (n = 42) in the ritonavir-boosted lopinavir group. Probabilities of viral failure were 0.027 (n = 4) in the efavirenz group and 0.020 (n = 3) in the ritonavir-boosted lopinavir group. The risk difference for viral rebound was 0.107 (1-sided 95% CI, 0.028 to ∞) and for viral failure was -0.007 (1-sided 95% CI, -0.036 to ∞). We rejected the null hypothesis that efavirenz is inferior to ritonavir-boosted lopinavir (P < .001) for both end points. By 48 weeks, CD4 cell percentage was 2.88% (95% CI, 1.26%-4.49%) higher in the efavirenz group than in the ritonavir-boosted lopinavir group.

CONCLUSIONS AND RELEVANCE

Among HIV-infected children exposed to nevirapine for prevention of mother-to-child transmission and with initial viral suppression with ritonavir-boosted lopinavir-based therapy, switching to efavirenz-based therapy compared with continuing ritonavir-boosted lopinavir-based therapy did not result in significantly higher rates of viral rebound or viral failure. This therapeutic approach may offer advantages in children such as these.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT01146873.

Growth reconstitution following antiretroviral therapy and nutritional supplementation: systematic review and meta-analysis

OBJECTIVE

As antiretroviral therapy (ART) expands for HIV-infected children, it is important to determine its impact on growth. We quantified growth and its determinants following ART in resource-limited (RLS) and developed settings.

DESIGN

Systematic review and meta-analysis.

METHODS

We searched publications reporting growth [weight-for-age (WAZ), height-for-age (HAZ), and weight-for-height (WHZ) z scores] in HIV-infected children following ART through August 2014. Inclusion criteria were as follows: younger than 18 years; ART; at least 20 patients; growth at ART; and post-ART growth. Standardized and overall weighted mean differences were calculated using random-effects models.

RESULTS

A total of 67 articles were eligible (RLS = 54; developed settings = 13). Mean age was 5.8 years, and comparable between settings (P = 0.90). Baseline growth was substantially lower in RLS vs. developed settings (WAZ -2.1 vs. -0.5; HAZ -2.2 vs. -0.9; both P < 0.01). Rate of weight but not height reconstitution during 12 and 24 months was higher in RLS (12-month WAZ change 0.84 vs. 0.17, P < 0.01). Growth deficits persisted in RLS after 2 years ART (P = 0.04). Younger cohort age was associated with greater growth reconstitution. Protease inhibitor and nonnucleoside reverse-transcriptase inhibitor regimens yielded comparable growth. Adjusting for age and setting, cohorts with nutritional supplements had greater growth gains (24-month rate difference: WAZ 0.55, P = 0.03; HAZ 0.60, P = 0.007). Supplement benefits were attenuated after adjusting for baseline cohort growth.

CONCLUSION

RLS children had substantial growth deficits compared with developed settings counterparts at ART; growth shortfalls in RLS persisted despite reconstitution. Earlier age and nutritional supplementation at ART may improve growth outcomes. Scant data on supplementation limit evaluation of impact and underscores need for systematic data collection regarding supplementation in pediatric ART programmes/cohorts.

Genetic Changes in HIV-1 Gag-Protease Associated with Protease Inhibitor-Based Therapy Failure in Pediatric Patients

Studies have shown a low frequency of HIV-1 protease drug resistance mutations in patients failing protease inhibitor (PI)-based therapy. Recent studies have identified mutations in Gag as an alternate pathway for PI drug resistance in subtype B viruses. We therefore genotyped the Gag and protease genes from 20 HIV-1 subtype C-infected pediatric patients failing a PI-based regimen. Major protease resistance mutations (M46I, I54V, and V82A) were identified in eight (40%) patients, as well as Gag cleavage site (CS) mutations (at codons 373, 374, 378, 428, 431, 449, 451, and 453) in nine (45%) patients. Four of these Gag CS mutations occurred in the absence of major protease mutations at PI failure. In addition, amino acid changes were noted at Gag non-CS with some predicted to be under HLA/KIR immune-mediated pressure and/or drug selection pressure. Changes in Gag during PI failure therefore warrant further investigation of the Gag gene and its role in PI failure in HIV-1 subtype C infection.

Tackling virological failure in HIV-infected children living in Africa

Drug resistance in HIV-infected children is one of the main contributors to antiretroviral treatment (ART) failure, especially in developing countries. Sub-Saharan Africa has the largest burden of pediatric HIV infection in the world. Herein, we systematically review the current status of ART failure in HIV-infected African children. A literature search for publications within 10 years was performed through PubMed to identify relevant articles. Included studies examined the impact of timing of ART initiation, criteria for diagnosing therapeutic failure, predictors of therapeutic failure, management strategies and future directions to minimize failure rates in these pediatric populations. Although there is scale-up of ART programs in Africa, novel therapeutic and management strategies are needed to overcome current challenges.

Factors Associated with the Development of Drug Resistance Mutations in HIV-1 Infected Children Failing Protease Inhibitor-Based Antiretroviral Therapy in South Africa

OBJECTIVE

Limited data are available from the developing world on antiretroviral drug resistance in HIV-1 infected children failing protease inhibitor-based antiretroviral therapy, especially in the context of a high tuberculosis burden. We describe the proportion of children with drug resistance mutations after failed protease inhibitor-based antiretroviral therapy as well as associated factors.

METHODS

Data from children initiated on protease inhibitor-based antiretroviral therapy with subsequent virological failure referred for genotypic drug resistance testing between 2008 and 2012 were retrospectively analysed. Frequencies of drug resistance mutations were determined and associations with these mutations identified through logistic regression analysis.

RESULTS

The study included 65 young children (median age 16.8 months [IQR 7.8; 23.3]) with mostly advanced clinical disease (88.5% WHO stage 3 or 4 disease), severe malnutrition (median weight-for-age Z-score -2.4 [IQR -3.7;-1.5]; median height-for-age Z-score -3.1 [IQR -4.3;-2.4]), high baseline HIV viral load (median 6.04 log10, IQR 5.34;6.47) and frequent tuberculosis co-infection (66%) at antiretroviral therapy initiation. Major protease inhibitor mutations were found in 49% of children and associated with low weight-for-age and height-for-age (p = 0.039; p = 0.05); longer duration of protease inhibitor regimens and virological failure (p = 0.001; p = 0.005); unsuppressed HIV viral load at 12 months of antiretroviral therapy (p = 0.001); tuberculosis treatment at antiretroviral therapy initiation (p = 0.048) and use of ritonavir as single protease inhibitor (p = 0.038). On multivariate analysis, cumulative months on protease inhibitor regimens and use of ritonavir as single protease inhibitor remained significant (p = 0.008; p = 0.033).

CONCLUSION

Major protease inhibitor resistance mutations were common in this study of HIV-1-infected children, with the timing of tuberculosis treatment and subsequent protease inhibitor dosing strategy proving to be important associated factors. There is an urgent need for safe, effective, and practicable HIV/tuberculosis co-treatment in young children and the optimal timing of treatment, optimal dosing of antiretroviral therapy, and alternative tuberculosis treatment strategies should be urgently addressed.

The effect of tuberculosis treatment on virologic and immunologic response to combination antiretroviral therapy among South African children

BACKGROUND

Many HIV-infected children are diagnosed with tuberculosis (TB), but the effect of TB treatment on virologic and immunologic response to combination antiretroviral therapy (cART) is not well documented.

METHODS

Secondary analysis of a prospective cohort of cART-naive HIV-infected South African children aged 0-8 years initiating cART to assess the effect of TB treatment at the time of cART initiation on virologic suppression (HIV RNA < 50 copies/mL), virologic rebound (HIV RNA > 1000 copies/mL after suppression), and CD4 cell percent (CD4%) increase during the first 24 months of cART.

RESULTS

Of 199 children (median age 2.1 years), 92 (46%) were receiving TB treatment at cART initiation. Children receiving and not receiving TB treatment at cART initiation had similar median baseline HIV RNA (5.4 vs. 5.6 copies/mL), median time to virologic suppression (6.2 months in each group, adjusted hazard ratio, 1.36, 95% confidence interval: 0.94 to 1.96), and rates of virologic rebound by 24 months (23% vs. 24%, adjusted hazard ratio 1.53, 95% confidence interval: 0.71 to 3.30). Children on TB treatment had significantly lower median CD4% at baseline (15.3% vs. 18.8%, P < 0.01) and during the first 12 months of cART but experienced similar median increases in CD4% at 6 months (9.9% vs. 9.6%), 12 months (14.2% vs. 11.9%), and 24 months of cART (14.5% vs. 14.2%). Exploratory analyses suggest that children receiving lopinavir/ritonavir-based cART and TB treatment may have inferior virologic and immunologic response compared with children receiving efavirenz-based cART.

CONCLUSIONS

Receiving TB treatment at the time of cART initiation did not substantially affect virologic or immunologic response to cART in young children.

Severe manifestations of extrapulmonary tuberculosis in HIV-infected children initiating antiretroviral therapy before 2 years of age

BACKGROUND

Early initiation of antiretroviral therapy (ART) in HIV-infected infants reduces mortality and opportunistic infections including tuberculosis (TB). However, young HIV-infected children remain at high risk of TB disease following mycobacterial infection. We document the spectrum of TB disease in HIV-infected children <2 years of age on ART.

METHODS

Retrospective cohort study; records of children <2 years of age initiating routine ART at Tygerberg Children's Hospital, Cape Town, January 2003-December 2010 were reviewed. Clinical data at ART initiation (baseline) and TB episodes after ART initiation, to June 2012, were recorded. TB immune reconstitution syndrome (TB-IRIS) and incident TB were defined as TB diagnosed within 3 months, and >3 months after, ART initiation respectively. Baseline characteristics were compared in children with TB-IRIS and those with incident TB.

RESULTS

In 494 children, median follow-up time on ART was 10.7 months. Fifty-five TB treatment episodes occurred after ART initiation: 23 (42%) TB-IRIS (incidence 21.9/100 person years (py)) and 32 (58%) incident TB (incidence 3.9/100 py). Children with TB-IRIS and those with incident TB had similar baseline characteristics. Eight of 10 cases of extrapulmonary TB were severe: 4 IRIS (2 meningitis, 1 disseminated, 1 pericarditis) and 4 incident cases (1 each miliary, meningitis, pericarditis and spinal). Fifty-one children (10%) died (mortality rate 5.96/100 py). Starting ART at <1 year of age approached significance as a risk factor for TB-IRIS (adjusted OR (AOR) 8.64, p=0.06); weight-for-age Z score <-2 predicted death (AOR 6.37, p<0.001).

CONCLUSIONS

Severe TB manifestations were observed among young HIV-infected children on ART.

Sex differences in responses to antiretroviral treatment in South African HIV-infected children on ritonavir-boosted lopinavir- and nevirapine-based treatment

BACKGROUND

While studies of HIV-infected adults on antiretroviral treatment (ART) report no sex differences in immune recovery and virologic response but more ART-associated complications in women, sex differences in disease progression and response to ART among children have not been well assessed. The objective of this study was to evaluate for sex differences in response to ART in South African HIV-infected children who were randomized to continue ritonavir-boosted lopinavir (LPV/r)-based ART or switch to nevirapine-based ART.

METHODS

ART outcomes in HIV-infected boys and girls in Johannesburg, South Africa from 2005-2010 were compared. Children initiated ritonavir-boosted lopinavir (LPV/r)-based ART before 24 months of age and were randomized to remain on LPV/r or switch to nevirapine-based ART after achieving viral suppression. Children were followed for 76 weeks post-randomization and then long-term follow up continued for a minimum of 99 weeks and maximum of 245 weeks after randomization. Viral load, CD4 count, lipids, anthropometrics, drug concentrations, and adherence were measured at regular intervals. Outcomes were compared between sexes within treatment strata.

RESULTS

A total of 323 children (median age 8.8 months, IQR 5.1-13.5), including 168 boys and 155 girls, initiated LPV/r-based ART and 195 children were randomized. No sex differences in risk of virological failure (confirmed viral load >1000 copies/mL) by 156 weeks post-randomization were observed within either treatment group. Girls switched to nevirapine had more robust CD4 count improvement relative to boys in this group through 112 weeks post-randomization. In addition, girls remaining on LPV/r had higher plasma concentrations of ritonavir than boys during post-randomization visits. After a mean of 3.4 years post-randomization, girls remaining on LPV/r also had a higher total cholesterol:HDL ratio and lower mean HDL than boys on LPV/r.

CONCLUSIONS

Sex differences are noted in treated HIV-infected children even at a young age, and appear to depend on treatment regimen. Future studies are warranted to determine biological mechanisms and clinical significance of these differences.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT00117728.

Plasma lopinavir concentrations predict virological failure in a cohort of South African children initiating a protease-inhibitor-based regimen

BACKGROUND

Poor adherence to antiretroviral therapy contributes to pharmacokinetic variability and is the major determinant of virological failure. However, measuring treatment adherence is difficult, especially in children. We investigated the relationship between plasma lopinavir concentrations, pretreatment characteristics and viral load >400 copies/ml.

METHODS

A total of 237 HIV-infected children aged 4-42 months on lopinavir/ritonavir oral solution were studied prospectively and followed for up to 52 weeks. Viral load and lopinavir concentration were measured at clinic visits 12, 24, 36 and 52 weeks after starting treatment. Cox multiple failure events models were used to estimate the crude and adjusted effect of lopinavir concentrations on the hazard of viral load >400 copies/ml.

RESULTS

The median (IQR) pretreatment CD4(+) T-lymphocyte percentage was 18.80% (12.70-25.35) and 53% of children had a pretreatment viral load >750,000 copies/ml. The median (IQR) weight-for-age and height-for-age z-scores were -2.17 (-3.35--2.84) and -3.34 (-4.57--3.41), respectively. Median (IQR) lopinavir concentrations were 8.00 mg/l (4.11-12.42) at median (IQR) 3.50 h (2.67-4.25) after the dose. The hazard of viral load >400 copies/ml was increased with lopinavir concentrations <1 mg/l versus ≥1 mg/l (adjusted hazard ratio 2.3 [95% CI 1.63, 3.26]) and lower height-for-age z-scores.

CONCLUSIONS

Low lopinavir concentrations (<1 mg/l) are associated with viraemia in children. This measure could be used as a proxy for adherence and to determine which children are more likely to fail.

Consequences of prior use of full-dose ritonavir as single protease inhibitor as part of combination antiretroviral regimens on the future therapy choices in HIV-1-infected children

BACKGROUND

South African HIV-infected infants below age 6 months and children younger than 3 years on concomitant antimycobacterial treatment received full-dose ritonavir single protease inhibitor (RTV-sPI), together with 2 nucleoside reverse transcriptase inhibitors, from 2004 until 2008. Use of RTV-sPI has been described as a risk factor for PI drug resistance, but the extent of this resistance is unknown.

AIM

This research assesses clinical and virological outcome of a pediatric RTV-sPI cohort at a large South African antiretroviral therapy (ART) site in a high-burden tuberculosis setting, including resistance mutations in those failing ART.

METHODS

All children initiated at Kalafong hospital before December 2008, who ever received RTV-sPI-based regimens, were assessed for patient outcome, virological failure and drug resistance. HIV viral loads were done 6-monthly and HIV genotyping since 2009.

RESULTS

There were 178 children who ever received RTV-sPI, with a mean age at ART initiation of 1.4 years. Of the 135 children (76%) with >6 months follow-up, 17 children (13%) never had viral suppression, whereas another 25 (18%) developed virological failure later. Nineteen of 26 children (73%) with genotypic resistance results had major PI mutations.

CONCLUSIONS

Treatment failure is not a universal feature in children with prior exposure to RTV-sPI regimens, but the significant proportion (31%) with virological failure is of concern due to high prevalence of major PI- and multiclass mutations. These children currently have no treatment options in the South African public sector, highlighting the urgent need for access to alternative ART regimens to ensure improved outcomes.

Mortality and long-term virologic outcomes in children and infants treated with lopinavir/ritonavir

BACKGROUND

There is scant data on young children receiving protease inhibitor-based therapy in real-life resource-limited settings and on the optimal timing of therapy among children who survive infancy. Our aim was to evaluate outcomes at the Hospital del Niño, Panama, where children have been routinely treated with lopinavir/ritonavir (LPV/r)-based therapy since 2002.

METHODS

Retrospective cohort analysis of all HIV-infected children enrolled in care between January 1, 1991, and June 1, 2011. Kaplan-Meier method and Cox proportional hazards regression were used to evaluate death, virologic suppression and virologic rebound.

RESULTS

Of 399 children contributing 1944 person-years of follow-up, 254 (63.7%) were treated with LPV/r and 94 (23.6%) were never treated with antiretrovirals (ARVs). Among infants, improved survival was associated with male gender (hazard rate of death[HRdeath] 0.54, 95% confidence interval [CI]: 0.32-0.92) and treatment with highly active antiretroviral therapy (HRdeath 0.32, 95% CI: 0.12-0.83), whereas residence outside of Panama City was associated with poorer survival (HRdeath 1.72, 95% CI: 1.01-2.94). Among children who survived to 1 year of age without exposure to ARVs, LPV/r-based therapy improved survival (HRdeath 0.07, 95% CI: 0.01-0.33). Virologic suppression was achieved in 42.1%, 70.5% and 85.1% by 12, 24 and 60 months of follow-up among children treated with LPV/r. Virologic suppression was not associated with prior ARV exposure or age at initiation of therapy but was associated with residence outside of Panama City (HR suppression 1.93, 95% CI: 1.19-3.14). Patients with a baseline viral load >100,000 copies/mL were less likely to achieve suppression (HR suppression 0.37, 95% CI: 0.21-0.66). No children who achieved virologic suppression after initiating LPV/r died.

CONCLUSIONS

LPV/r-based therapy improved survival not only in infants but also in children over 1 year of age. Age at initiation of LPV/r-based therapy or prior ARVs did not impact virologic outcomes.

Adherence and viral suppression among infants and young children initiating protease inhibitor-based antiretroviral therapy

BACKGROUND

High levels of adherence to antiretroviral therapy are considered necessary to achieve viral suppression. We analyzed data from a cohort of HIV-infected children who were <2 years of age receiving protease inhibitor-based antiretroviral therapy to investigate associations between viral suppression and adherence ascertained using different methods.

METHODS

Data were from the prerandomization phase of a clinical trial in South Africa of HIV-infected children initiating either ritonavir-boosted lopinavir (LPV/r) or ritonavir-based antiretroviral therapy. At scheduled visits during the first 24 weeks of enrollment, study pharmacists measured quantities of medications returned to the clinic. Caregivers answered questionnaires on missed doses and adherence barriers. Associations between adherence and viral suppression (HIV-1 RNA <400 copies/mL) were investigated by regimen.

RESULTS

By 24 weeks, 197 of the 269 (73%) children achieved viral suppression. There was no association between viral suppression and caregiver reported missed doses or adherence barriers. For children receiving the LPV/r-based regimen, medication return adherence to each of the 3 drugs in the regimen (LPV/r, lamivudine or stavudine) individually or together was associated with viral suppression at different adherence thresholds. For example, <85% adherence to any of the 3 medications significantly increased odds of lack of viral suppression (odds ratio: 2.30, 95% confidence interval: 1.30-4.07, P = 0.004). In contrast, for children receiving the ritonavir-based regimen, there was no consistent pattern of association between medication return and viral suppression.

CONCLUSIONS

Caregiver reports of missed doses did not predict virologic response to treatment. Pharmacist medication reconciliation correlated strongly with virologic response for children taking a LPV/r-based regimen and appears to be a valid method for measuring pediatric adherence.

A meta-analysis of adherence to antiretroviral therapy and virologic responses in HIV-infected children, adolescents, and young adults

The relationship between adherence to antiretroviral therapy (ART) and virologic outcomes in HIV+ children, adolescents, and young adults has been notably understudied, with much of the extant research focused on specific sub-literatures, such as resource-limited regions, specific clinical outcomes and time frames. The authors sought to better characterize the relationship between adherence to ART and virologic functioning along various sample and methodological factors. The authors conducted a meta-analysis of thirty-seven studies and utilized a random effects model to generate weighted mean effect sizes. In addition, the authors conducted meta-ANOVAs to examine potential factors influencing the relationship between adherence and three categories of clinical outcomes, specifically Viral Load (VL) <100, VL < 400, and continuously measured VL. The analyses included 5,344 HIV+ children, adolescents, and young adults. The relationship between adherence behaviors and virologic outcomes varied across different methods of measurement and analysis. The relationship between adherence and continuously measured VL was significantly larger than for dichotomously-coded VL < 400 at Qb (20.69(1), p < .0005). Caregiver self-report indices elicited very small to small magnitude effects across both VL < 100 and VL < 400 outcomes and combined informant reporting (youth/adolescent and parent) produced significantly larger effects than caregiver report alone with adherence and VL < 400 outcomes at Qb (9.28(1), p < .005). More recently published trials reported smaller relationships between adherence and categorical clinical outcomes, such that year of publication significantly negatively correlated with VL < 100 (r = -.71(14), p < .005) and VL < 400 (r = -.43(26), p < .02). The data suggest that the magnitude of the relationship between ART adherence and virologic outcomes among heterogeneous samples of HIV+ children, adolescents and young adults varies across virologic outcomes and may be affected by moderating sample and methodological factors. Methodological and research recommendations for the interpretation of the current findings as well as for future HIV adherence related research are presented.

PEPFAR scale-up of pediatric HIV services: innovations, achievements, and challenges

HIV/AIDS has had a profound impact on children around the world since the start of the epidemic. There are currently 3.4 million children under the age of 15 years living with HIV globally, and more than 450,000 children currently receiving lifesaving antiretroviral treatment. This article describes efforts supported by the President's Emergency Plan for AIDS Relief (PEPFAR) to expand access to treatment for children living with HIV in high-burden countries. The article also highlights a series of case studies that illustrate the impact that the PEPFAR initiative has had on the pediatric HIV epidemic. Through its support of host governments and partner organizations, the PEPFAR initiative has expanded HIV testing and treatment for pregnant women to reduce vertical transmission of HIV, increased access to early infant diagnosis for HIV-exposed infants, improved training and resources for clinicians who provide pediatric care and antiretroviral treatment, and, through public-private partnerships with pharmaceutical manufacturers, helped increase the number of medications available for the treatment of HIV-infected children in resource-limited settings.

Feasibility and effectiveness of early initiation of combination antiretroviral therapy in HIV-infected infants in a government clinic of Kwazulu-Natal, South Africa

A recent randomized trial showed dramatic improvement in survival of HIV-infected infants receiving early combination antiretroviral therapy (cART). However, few data are available for resource-limited settings. Therefore we conducted a chart review of HIV-infected infants initiated on cART between 2005 and 2008. Of 129 treated infants, 94 completed 6 months, 62 completed 12 months, and 39 completed 18 months of cART. Median age at initiation of cART was 8.6 months (range 2.1-11.9) and 77.2% had advanced disease. Undetectable VL was found in 78.8% of children who reached 18 months of treatment. CD4% increased from a median of 15.4% at baseline to 33.1% at 18 months. Weight for age Z-score increased from a mean ± SD of -2.7 ± 1.97 to 0.02 ± 1.10 at 18 months. Findings show favourable response to cART in HIV-infected infants outside a research environment, despite initial advanced disease. Efforts should be made to initiate cART as early as possible.

Switching children previously exposed to nevirapine to nevirapine-based treatment after initial suppression with a protease-inhibitor-based regimen: long-term follow-up of a randomised, open-label trial

BACKGROUND

Protease-inhibitor-based treatment is recommended as first-line for infants infected with HIV who have been previously exposed to nevirapine prophylaxis. However, long-term use poses adherence challenges, is associated with metabolic toxic effects, restricts second-line options, and is costly. We present the long-term outcomes of switching nevirapine-exposed children to nevirapine-based treatment after effective suppression of virus replication with a protease-inhibitor-based regimen.

METHODS

We did a randomised trial to compare long-term viral suppression with nevirapine-based versus protease-inhibitor-based (ritonavir-boosted lopinavir) treatment in children who had achieved suppression with protease-inhibitor-based treatment. Randomisation (1:1) was by cohort blocks of variable size between eight and 12. Eligible children were younger than 24 months who were previously exposed to nevirapine for prevention of mother-to-child transmission, and achieved virological suppression of less than 400 copies per mL when treated with the regimen based on ritonavir-boosted lopinavir in Johannesburg, South Africa. We gave all drugs as liquids and adjusted doses at each visit in accordance with growth. We continued follow-up for a minimum of 90 weeks and maximum of 232 weeks after randomisation. We quantified HIV RNA every 3 months. Our primary endpoint was any viraemia greater than 50 copies per mL. Our analysis was by modified intention to treat. This study is registered with ClinicalTrials.gov, number NCT00117728.

FINDINGS

We followed up the children for a median of 156 weeks and there were three deaths in each group. Children in the switch group (Kaplan-Meier probability 0·595) were less likely to experience non-suppression greater than 50 copies per mL than in the control group (0·687; p=0·01) and had better CD4 and growth responses initially after switching (52 children in the switch group vs 66 control group met this endpoint). By 156 weeks after randomisation, more children had virological failure--which we defined as confirmed viraemia of more than 1000 copies per mL--in the switch group (22 children) than in the control group (ten children; p=0·009). We detected all 22 failures in the switch group by 52 weeks compared with five in the control group. Virological failure was related to non-adherence and pretreatment drug resistance. In children without pretreatment drug resistance, we did not identify a significant difference in virological failure between the switch (Kaplan-Meier probability 0·140) and control (0·095) groups (p=0·34; seven failures in the switch group vs five in the control group). Children in the switch group were significantly more likely to develop grade 1-3 alanine aminotransferase abnormalities over the duration of follow-up.

INTERPRETATION

Viral-load testing through 52 weeks can identify all children likely to fail this protease-inhibitor-switch strategy. Switching children once suppressed to a nevirapine-based regimen might be a valuable treatment option if adequate viral-load monitoring can be done.

FUNDING

National Institutes of Child Health and Human Development and Secure the Future Foundation.

Unresolved antiretroviral treatment management issues in HIV-infected children

Antiretroviral therapy in children has expanded dramatically in low-income and middle-income countries. The World Health Organization revised its pediatric HIV guidelines to recommend initiation of antiretroviral therapy in all HIV-infected children younger than 2 years, regardless of CD4 count or clinical stage. The number of children starting life-long antiretroviral therapy should therefore expand dramatically over time. The early initiation of antiretroviral therapy has indisputable benefits for children, but there is a paucity of definitive information on the potential adverse effects. In this review, a comprehensive literature search was conducted to provide an overview of our knowledge about the complications of treating pediatric HIV. Antiretroviral therapy in children, as in adults, is associated with enhanced survival, reduction in opportunistic infections, improved growth and neurocognitive function, and better quality of life. Despite antiretroviral therapy, HIV-infected children may continue to lag behind their uninfected peers in growth and development. In addition, epidemic concurrent conditions, such as tuberculosis, malaria, and malnutrition, can combine with HIV to yield more rapid disease progression and poor treatment outcomes. Additional studies are required to evaluate the long-term effects of antiretroviral therapy in HIV-infected infants, children, and adolescents, particularly in resource-limited countries where concomitant infections and conditions may enhance the risk of adverse effects. There is an urgent need to evaluate drug-drug interactions in children to determine optimal treatment regimens for both HIV and coinfections.

Virological response and resistance profiles after 18 to 30 months of first- or second-/third-line antiretroviral treatment: a cross-sectional evaluation in HIV type 1-infected children living in the Central African Republic

A total of 242 HIV-1-infected children were followed up at the Complexe Pédiatrique of Bangui, Central African Republic, including 165 receiving antiretroviral treatment in first- (n=150) or second-/third-line (n=15) regimens. They were prospectively included in a study, in 2009, to assess their virological status and prevalence of antiretroviral drug-resistance mutations in cases of virological failure, according to revised 2010 WHO criteria (e.g., HIV-1 RNA >3.7 log(10) copies/ml). Detectable plasma HIV-1 RNA was observed in 53% of children under first-line treatment, and virological failure was diagnosed in 40%, which was associated in 85% of cases with viruses harboring at least one drug-resistance mutation to nucleoside reverse transcriptase inhibitors (NRTI) or nonnucleoside reverse transcriptase inhibitors (NNRTI), and in 36% of cases with at least one major drug-resistance mutation to NRTI or NNRTI when excluding the M184V mutation. Overall, the proportion of children receiving a first-line regimen for a median of 18 months with virological failure associated with drug-resistance mutations, and thus eligible for a second-line treatment, was estimated at 34% of the whole cohort. In children under second-/third-line therapy, virological failure occurred in 47%, plus at least one major drug-resistance mutation to NRTI or NNRTI, though less commonly to protease inhibitors. Taken together, these findings argue in favor of the urgent need to improve distribution of pediatric antiretroviral drugs in the Central African Republic, to increase adherence by treated children, and to offer adequate HIV biological monitoring.

Early antiretroviral therapy in HIV-1-infected infants, 1996-2008: treatment response and duration of first-line regimens

OBJECTIVE

To investigate virological and immunological response to antiretroviral therapy (ART), and predictors of switching and interrupting treatment among infants starting ART across Europe.

DESIGN

Cohort study.

METHODS

Nine cohorts from 13 European countries contributed data on HIV-infected infants born 1996-2008 and starting ART before age 12 months. Logistic and linear regression, and competing risks methods were used to assess predictors of virological (viral load <400 copies/ml) and immunological (change in CD4 Z-score) response, switching to second-line ART and treatment interruptions with viral load less than 400 copies/ml.

RESULTS

A total of 437 infants were followed for median 5.9 (interquartile range 2.3-7.6) years after starting ART; 30% had an AIDS diagnosis prior to ART initiation. 53% had suppressed viral load <400 copies/ml at 12 months in 1996-1999, increasing to 77% in 2004-2008. Virological and immunological responses at 12 months varied by initial ART type (P < 0.001 and P = 0.03, respectively), with four-drug nonnucleoside reverse transcriptase inhibitor (NNRTI)-based regimens being superior [virological response <400 copies/ml adjusted odds ratio = 3.00, 95% confidence interval (CI) 1.24-7.23; mean increase in CD4 Z-score coefficient = 0.64, 95% CI 0.10-1.17] to both three-drug NNRTI-based (reference) and boosted protease inhibitor regimens which were similar. Rates of switching to second-line ART were lower among children starting four-drug NNRTI-based and boosted protease inhibitor-based regimens compared with three-drug NNRTI regimens (P = 0.03). Sixty five percent of infants remained on first-line ART without treatment interruption after 5 years.

CONCLUSION

Effective and prolonged responses to first-line ART can now be achieved in infants starting early ART outside trial settings. Superior responses to four-drug NNRTI compared with boosted protease inhibitor or three-drug NNRTI regimens need further evaluation, as does treatment interruption following early ART.

Tuberculosis in human immunodeficiency virus infected Ugandan children starting on antiretroviral therapy

OBJECTIVE

To identify the incidence of tuberculosis (TB) in human immunodeficiency virus (HIV) infected children in a resource-limited setting before and after initiation of antiretroviral therapy (ART), and to assess the impact of TB screening by tuberculin skin testing and clinical history.

METHODS

A retrospective cohort study of 1806 HIV-infected children and adolescents (age <18 years) initiating ART from 2003 to 1 July 2006 in Kampala, Uganda. A TB screening program was instituted clinic-wide in January 2006.

RESULTS

Of 311 (17.2%) HIV-infected children, 171 had been diagnosed with TB before and 140 after ART initiation. During the first 100 days of ART, risk of a new TB diagnosis was 2.7-fold higher compared to the pre-ART period (RR 2.7, 95%CI 2.1-3.5, P < 0.001). After 100 days of ART, the TB incidence rate decreased to below pre-ART levels (RR 0.41, 95%CI 0.30-0.54, P = 0.002). After TB screening was instituted in 2006, the proportion of new TB cases diagnosed after starting ART decreased by 70% (95%CI 51-82, P < 0.001), abating the early excess risk.

CONCLUSIONS

TB is common among African children and adolescents initiating ART in sub-Saharan Africa. More aggressive screening for active TB before starting ART can diminish the rate of TB during immune reconstitution. Future studies are needed to determine optimal screening practices for HIV-infected children.

Rapid development of antiretroviral drug resistance mutations in HIV-infected children less than two years of age initiating protease inhibitor-based therapy in South Africa

Data on the development of antiretroviral drug resistance in HIV-1-infected children receiving protease inhibitor (PI)-based antiretroviral therapy (ART) are limited. We examined antiretroviral resistance among a cohort of 323 South African HIV-infected children <2 years old exposed to nevirapine for prevention of mother-to-child transmission. Ritonavir (RTV) was used initially for 138 children who were <6 months old or receiving antimycobacterial therapy; otherwise children received lopinavir/ritonavir (LPV/r)-based ART. HIV-1 population sequencing of the pol gene was conducted on all pretreatment samples and on posttreatment samples for children who did not achieve HIV-1 plasma RNA <400 copies/ml by 52 weeks. Among children in the cohort, 38 died, 22 had <24 weeks follow-up, 209 achieved virologic suppression, and 54 did not. Of 41 children without virologic suppression with posttreatment HIV genotype data available, major resistance mutations were found in 32 (78%): 14 (36%) had PI mutations including V82A, M46I, and L90M; 29 (71%) had M184V/I; and three had NNRTI mutations (K103N, Y181C, and G190A). Among the children who did not achieve virologic suppression, none of the seven children treated exclusively with LPV/r developed PI-related mutations, compared with 14 of 32 (44%) who received RTV-based regimens (p=0.036); PI genotypes were unavailable for two children. Seventy-eight percent of children without virologic suppression developed resistance mutations that impact second-line ART options. Only children who received RTV-based ART developed major PI-related resistance mutations, and use of this regimen should be avoided.

Lopinavir/ritonavir-based antiretroviral therapy in human immunodeficiency virus type 1-infected naive children: rare protease inhibitor resistance mutations but high lamivudine/emtricitabine resistance at the time of virologic failure

BACKGROUND

Lopinavir/ritonavir (LPV/r) is now the protease inhibitor regimen of choice in the first-line antiretroviral therapy for children <6 years of age.

METHODS

We included all the human immunodeficiency virus (HIV) type 1-infected highly active antiretroviral therapy (HAART)-naive children who started an LPV/r-based regimen between 2000 and 2009 at the Necker Hospital (Paris, France). Virologic failure (VF) was defined as an HIV-RNA ≥50 copies/mL. Resistance genotypic test was performed in case of VF.

RESULTS

A total of 43 children were included at a median age of 4.8 years (1.8-8.0). Median level of HIV RNA and percentage of CD4 cell count was 5.5 log₁₀ copies/mL (4.6-6) and 15% (8-27.5), respectively. HAART included LPV/r and 2 nucleoside reverse-transcriptase inhibitors, mainly lamivudine (3TC), zidovudine, and/or abacavir. The median follow-up period was 36 months (18-72). Less than 50 copies/mL of HIV RNA was observed in 46%, 67%, and 70% of the children at months 6, 9, and 12, respectively. In all, 20 children (46.5%) experienced a VF. The risk factors of primary VF were a young age and a low socioeconomic status. The genotypic resistance test, performed for 18 of 20 children with VF, revealed 1 LPV/r-resistant virus and protease inhibitor-related major mutations without LPV/r resistance in 2 other children. Of the 18 children with VF, 15 received a 3TC-based HAART: 12 of 15 (80%) harbored a 3TC-resistant virus. No virus resistant to zidovudine or abacavir was found.

CONCLUSION

In all, 70% of HAART-naive children had virologic success at month 12. The selection of LPV-resistant strains was a rare event. A high rate of selection of 3TC-mutations strengthens the recommendation to prefer a first-line 3TC-sparing regimen, particularly for children with risk factors of poor adherence.

HIV-1 drug resistance at antiretroviral treatment initiation in children previously exposed to single-dose nevirapine

OBJECTIVE

To describe the prevalence of HIV-1 drug resistance mutations at the time of treatment initiation in a large cohort of HIV-infected children previously exposed to single-dose nevirapine (sdNVP) for prevention of transmission.

DESIGN

Drug resistance mutations were measured pretreatment in 255 infants and young children under 2 years of age in South Africa exposed to sdNVP and initiating ritonavir-boosted lopinavir-based therapy. Those who achieved viral suppression were randomized to either continue the primary regimen or to switch to a nevirapine-based regimen. Pretreatment samples were tested using population sequencing and real time allele-specific PCR (AS-PCR) to detect Y181C and K103N minority variants. Those with confirmed viremia more than 1000 copies/ml by 52 weeks postrandomization in the switch group were defined as having viral failure.

RESULTS

Nonnucleoside reverse transcriptase inhibitor (NNRTI) mutations, predominantly Y181C, were detected by either method in 62% of infants less than 6 months of age, in 39% of children 6-12 months of age, 22% 12-18 months, and 16% 18-24 months (P = <0.0001). NNRTI mutations detected by genotyping, but not K103N or Y181C mutations detected only by AS-PCR, were associated with viral failure in the switch group.

CONCLUSION

The prevalence of mutations known to compromise primary NNRTI-based therapy is high in sdNVP-exposed children, supporting current guidelines recommending use of protease inhibitor-based regimens for young children. Standard genotyping is adequate to identify children who could benefit from switching to NNRTI-based therapy.

Antiretroviral therapy outcomes in HIV-infected children after adjusting protease inhibitor dosing during tuberculosis treatment

BACKGROUND

Modification of ritonavir-boosted lopinavir (LPV/r)-based antiretroviral therapy is required for HIV-infected children co-treated for tuberculosis (TB). We aimed to determine virologic and toxicity outcomes among TB/HIV co-treated children with the following modifications to their antiretroviral therapy (ART): (1) super-boosted LPV/r, (2) double-dose LPV/r or (3) ritonavir.

METHODS AND FINDINGS

A medical record review was conducted at two clinical sites in Johannesburg, South Africa. The records of children 6-24 months of age initiating LPV/r-based therapy were reviewed. Children co-treated for TB were categorized based on the modifications made to their ART regimen and were compared to children of the same age at each site not treated for TB. Included are 526 children, 294 (56%) co-treated for TB. All co-treated children had more severe HIV disease, including lower CD4 percents and worse growth indicators, than comparisons. Children in the super-boosted group (n = 156) were as likely to be virally suppressed (<400 copies/ml) at 6 months as comparisons (69.2% vs. 74.8%, p = 0.36). Children in the double-dose (n = 47) and ritonavir groups (n = 91) were significantly less likely to be virally suppressed at 6 months (53.1% and 49.3%) than comparisons (74.8% and 82.1%; p = 0.02 and p<0.0001, respectively). At 12 months only children in the ritonavir group still had lower rates of virological suppression relative to comparisons (63.9% vs 83.3% p<0.05). Grade 1 or greater ALT elevations were more common in the super-boosted (75%) than double-dose (54.6%) or ritonavir (33.9%) groups (p = 0.09 and p<0.0001) but grade 3/4 elevations were observed in 3 (13.6%) of the super-boosted, 7 (15.9%) of the double-dose and 5 (8.9%) of the ritonavir group (p = 0.81 and p = 0.29).

CONCLUSION

Good short-term virologic outcomes were achieved in children co-treated for TB and HIV who received super-boosted LPV/r. Treatment limiting toxicity was rare. Strategies for increased dosing of LPV/r with TB treatment warrant further investigation.

Reuse of nevirapine in exposed HIV-infected children after protease inhibitor-based viral suppression: a randomized controlled trial

CONTEXT

Protease inhibitor (PI)-based therapy is recommended for infants infected with human immunodeficiency virus (HIV) who were exposed to nevirapine for prevention of mother-to-child HIV transmission. However, there are limitations of continuing PI-based therapy indefinitely and reuse of nevirapine has many advantages.

OBJECTIVE

To test whether nevirapine-exposed infants who initially achieve viral suppression with PI-based therapy can maintain viral suppression when switched to nevirapine-based therapy.

DESIGN, SETTING, AND PATIENTS

Randomized trial conducted between April 2005 and May 2009 at a hospital in Johannesburg, South Africa, among 195 children who achieved viral suppression less than 400 copies/mL for 3 or more months from a cohort of 323 nevirapine-exposed children who initiated PI-based therapy before 24 months of age.

INTERVENTIONS

Control group children continued to receive ritonavir-boosted lopinavir, stavudine, and lamivudine (n = 99). Switch group children substituted nevirapine for ritonavir-boosted lopinavir (n = 96).

MAIN OUTCOME MEASURES

Children were followed up for 52 weeks after randomization. Plasma HIV-1 RNA of greater than 50 copies/mL was the primary end point. Confirmed viremia greater than 1000 copies/mL was used as a criterion to consider regimen changes for children in either group (safety end point).

RESULTS

Plasma viremia greater than 50 copies/mL occurred less frequently in the switch group (Kaplan-Meier probability, 0.438; 95% CI, 0.334-0.537) than in the control group (0.576; 95% CI, 0.470-0.668) (P = .02). Confirmed viremia greater than 1000 copies/mL occurred more frequently in the switch group (0.201; 95% CI, 0.125-0.289) than in the control group (0.022; 95% CI, 0.004-0.069) (P < .001). CD4 cell response was better in the switch group (median CD4 percentage at 52 weeks, 34.7) vs the control group (CD4 percentage, 31.3) (P = .004). Older age (relative hazard [RH], 1.71; 95% CI, 1.08-2.72) was associated with viremia greater than 50 copies/mL in the control group. Inadequate adherence (RH, 4.14; 95% CI, 1.18-14.57) and drug resistance (RH, 4.04; 95% CI, 1.40-11.65) before treatment were associated with confirmed viremia greater than 1000 copies/mL in the switch group.

CONCLUSION

Among HIV-infected children previously exposed to nevirapine, switching to nevirapine-based therapy after achieving viral suppression with a ritonavir-boosted lopinavir regimen resulted in lower rates of viremia greater than 50 copies/mL than maintaining the primary ritonavir-boosted lopinavir regimen.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT00117728.