Abacavir safety and effectiveness in young infants with HIV in South African observational cohorts.

BACKGROUND: WHO guidelines recommend abacavir in first-line antiretroviral treatment for children and neonates. However, there is no approved dose <3 months of age, and data in neonates are limited. METHODS: We included infants who initiated ART aged <3 months, between 2006 and 2019, in nine South African cohorts. In those who received abacavir or zidovudine, we described antiretroviral discontinuation rates; and 6- and 12-month viral suppression (<400 copies/mL). We compared infants aged <28 and ≥28 days, those weighing <3 and ≥3 kg. RESULTS: Overall 837/1643 infants (51%) received abacavir and 443 (27%) received zidovudine. Median (interquartile range, IQR) age was 52 days (23-71), CD4 percentage was 27.9 (19.2-38.0), and weight was 4.0 kg (3.0-4.7) at ART initiation. In those with ≥1 month's follow-up, 100/718 (14%) infants discontinued abacavir, at a median of 17.5 months (IQR 6.5-39.5). Abacavir discontinuations did not differ by age or weight category (p = 0.4 and 0.2, respectively); and were less frequent than zidovudine discontinuations (adjusted hazard ratio 0.14, 95% confidence interval 0.10-0.20). Viral suppression at 12 months occurred in 43/79 (54%) and 130/250 (52%) of those who started abacavir aged <28 and ≥28 days, respectively (p = 0.8); 11/19 (58%) and 31/60 (52%) in those who weighed <3 and ≥3 kg, respectively (p = 0.6); and 174/329 (53%) in those on abacavir versus 77/138 (56%) in those on zidovudine (adjusted odds ratio 1.8, 95% confidence interval 1.0-3.2). CONCLUSION: Our data suggest that abacavir may be used safely in infants <28 days old or who weigh <3 kg.

Ongoing High Prevalence of Severe Immune Suppression Among Children in South Africa.

BACKGROUND: Among children in Southern Africa severe immune suppression (SIS) has declined, but most continue to initiate antiretroviral therapy (ART) with SIS. SETTING: Using data from South Africa, we describe SIS at ART start and on ART between 2007 and 2020, among children <5 years with a CD4%/cell count at ART start and ≥1 subsequent measure. METHODS: Gap in care was defined as >9 months without a recorded visit. We defined SIS according to age and CD4%/cell count. A multistate model was used to estimate transition probabilities between 5 states: SIS on ART; Stable, not SIS; Early Gap, commencing <9 months from ART start; Late Gap, commencing ≥9 months on ART; and Death. RESULTS: Among 2536 children, 70% had SIS at ART start, and 36% experienced SIS on ART. An increasing proportion were age <1 year at ART initiation (2007-2009: 43% to 2013-2020: 55%). Increasingly, SIS on ART occurred after a gap, in those with SIS on ART for >1 year, and after a period of unknown immune status. Later year of ART initiation was associated with reduced transition from SIS on ART to Stable. Infants and those initiating ART with SIS were more likely to transition from Stable to SIS. Viremia strongly predicted death from both the on ART states. CONCLUSIONS: Increasingly SIS occurred among ART-experienced children. Those starting ART with SIS and during infancy remained especially vulnerable to SIS once on treatment. Managing ART in these children may be more complex and further reducing AIDS-related mortality is likely to remain challenging.

Virologic non-suppression and early loss to follow up among pregnant and non-pregnant adolescents aged 15-19 years initiating antiretroviral therapy in South Africa: a retrospective cohort study.

INTRODUCTION: Older adolescents aged 15-19 years continue to have high rates of loss to follow up (LTFU), and high rates of virologic non-suppression (VNS) compared to younger adolescents and adults. Adolescent females are at risk of pregnancy, which puts those living with HIV at a dual vulnerability. Our study assessed the factors associated with VNS and LTFU in older adolescents (including pregnant females) who initiated antiretroviral therapy (ART) in South Africa. METHODS: We included adolescents aged 15-19 years initiating ART between 2004 and 2019, with ≥ one viral load (VL) measurement between 4 and 24.5 months, and ≥ 6 months follow-up, from six South African cohorts of the International epidemiology Databases to Evaluate AIDS-Southern Africa (IeDEA-SA). We defined VNS as VL ≥400 copies/ml and LTFU as not being in care for ≥180 days from ART start and not known as transferred out of the clinic or dead in the first 24 months on ART. We examined factors associated with VNS and LTFU using Fine&Gray competing risk models. RESULTS: We included a total of 2733 adolescents, 415 (15.2%) males, median (IQR) age at ART start of 18.6 (17.3, 19.4) years. Among females, 585/2318 (25.2%) were pregnant. Over the 24-month follow-up, 424 (15.5%) of all adolescents experienced VNS: range (11.1% pregnant females and 20.5% males). Over half of all adolescents were LTFU before any other event could occur. The hazard of VNS reduced with increasing age and CD4 count above 200 cells/µl at ART initiation among all adolescents having adjusted for all measured patient characteristics [adjusted sub-distribution hazard ratio (aSHR) 19 vs. 15 years: 0.50 (95% CI: 0.36, 0.68), aSHR: >500 vs. ≤200 cells/µl: 0.22 (95% CI: 0.16, 0.31)]. The effect of CD4 count persisted in pregnant females. Increasing age and CD4 count >200 cells/µl were risk factors for LTFU among all adolescents. CONCLUSIONS: Older adolescents had a high risk of LTFU shortly after ART start and a low risk of VNS, especially those initiating treatment during pregnancy. Interventions addressing adherence and retention should be incorporated into adolescent-friendly services to prevent VNS and LTFU and endeavour to trace lost adolescents as soon as they are identified.

Optimised paediatric antiretroviral treatment to achieve the 95-95-95 goals.

While the progress towards reaching the UNAIDS 95-95-95 targets in South African adults seems promising, the progress in the paediatric population is lagging far behind; only 79% percent of children living with HIV know their status. Of these, only 47% are on treatment, and a mere 34% of those are virally suppressed. Thus, virological suppression has been attained in only 13% of children living with HIV in South Africa. Multiple factors contribute to the high treatment failure rate, one of them being a lack of paediatric-friendly antiretroviral treatment (ART) formulations. For example, the Lopinavir/ritonavir syrup, which is the current mainstay of ART for young children, has an extremely unpleasant taste, contributing to the poor tolerability and lack of adherence by children using the formulation. Furthermore, the lack of appropriate formulations limits the optimisation of regimens, especially for young children and those who cannot swallow tablets. Switching from syrups to dispersible tablets will improve ease of administration and adherence and result in cost-saving. Despite the approval of simplified paediatric-friendly formulations internationally, including other sub-Saharan African countries, unnecessary delays are experienced in South Africa. Clinician groups and community organisations must speak up and demand that approvals be expedited to ensure the delivery of life-changing and life-saving formulations to our patients as a matter of urgency.

The Etiology of Pneumonia in HIV-1-infected South African Children in the Era of Antiretroviral Treatment: Findings From the Pneumonia Etiology Research for Child Health (PERCH) Study.

BACKGROUND: HIV-1 infection predisposes to an increased burden of pneumonia caused by community-acquired and opportunistic pathogens. METHODS: Within the context of the Pneumonia Etiology Research for Child Health case-control study of under 5 pneumonia, we investigated the etiology of World Health Organization-defined severe/very severe pneumonia requiring hospitalization in South African HIV-infected children. Nasopharyngeal-oropharyngeal swabs and blood, collected from cases and age- and season-matched HIV-infected controls attending outpatient antiretroviral therapy (ART) clinics, were analyzed using molecular diagnostic methods. Cases were also investigated for tuberculosis. Etiologic fractions among cases with radiologically confirmed pneumonia were derived using Bayesian analytic techniques. RESULTS: Of 115 HIV-infected cases, 89 (77.4%) had radiologically confirmed pneumonia. Severe immunosuppression (adjusted odds ratio, 32.60; 95% confidence interval, 7.25-146.64) was significantly associated with radiologically confirmed pneumonia. Cotrimoxazole prophylaxis (46.4% vs. 77.4%) and ART (28.2% vs. 83.1%) coverage were significantly lower in cases compared with ART-clinic controls. An etiologic agent was identified in 99.0% of the radiologically confirmed cases. The 'top 4' pathogens associated with radiologically confirmed pneumonia were Pneumocystis jirovecii [23.0%; 95% credible interval (CrI), 12.4%-31.5%], Staphylococcus aureus (10.6%; 95% CrI, 2.2%-20.2%), pneumococcus (9.5%; 95% CrI, 2.2%-18.0%) and respiratory syncytial virus (9.3%; 95% CrI, 2.2%-14.6%). Bacteremia (6.7%) and in-hospital death (10.1%) were frequent among those with radiologically confirmed disease. CONCLUSIONS: Pneumocystis jirovecii, S. aureus, pneumococcus and respiratory syncytial virus contribute a considerable burden of radiologically confirmed pneumonia in South African HIV-infected children under 5 years. Expediting access to ART and cotrimoxazole prophylaxis would decrease the burden of pneumonia in these children.

Virologic response of adolescents living with perinatally acquired HIV receiving antiretroviral therapy in the period of early adolescence (10-14 years) in South Africa.

BACKGROUND AND OBJECTIVES: Adolescents living with perinatally acquired HIV (ALPHIV) on antiretroviral therapy (ART) have been noted to have poorer adherence, retention and virologic control compared to adolescents with non-perinatally acquired HIV, children or adults. We aimed to describe and examine factors associated with longitudinal virologic response during early adolescence. DESIGN: A retrospective cohort study. METHODS: We included ALPHIV who initiated ART before age 9.5 years in South African cohorts of the International epidemiology Database to Evaluate AIDS-Southern Africa (IeDEA-SA) collaboration (2004-2016); with viral load (VL) values <400 copies/ml at age 10 years and at least one VL measurement after age 10 years. We used a log-linear quantile mixed model to assess factors associated with elevated (75th quantile) VLs. RESULTS: We included 4396 ALPHIV, 50.7% were male, with median (interquartile range) age at ART start of 6.5 (4.5, 8.1) years. Of these, 74.9% were on a non-nucleoside reverse transcriptase inhibitor (NNRTI) at age 10 years. After adjusting for other patient characteristics, the 75th quantile VLs increased with increasing age being 3.13-fold (95% CI 2.66, 3.68) higher at age 14 versus age 10, were 3.25-fold (95% CI 2.81, 3.75) higher for patients on second-line protease-inhibitor and 1.81-fold for second-line NNRTI-based regimens (versus first-line NNRTI-based regimens). There was no difference by sex. CONCLUSIONS: As adolescents age between 10 and 14 years, they are increasingly likely to experience higher VL values, particularly if receiving second-line protease inhibitor or NNRTI-based regimens, which warrant adherence support interventions.

Recording of HIV viral loads and viral suppression in South African patients receiving antiretroviral treatment: a multicentre cohort study.

BACKGROUND: Viral suppression in patients on antiretroviral treatment (ART) is critical to reducing HIV transmission and HIV-related mortality. Although many studies have evaluated factors associated with viral suppression, few have assessed the extent to which missing viral load data may bias results. METHODS: We included data on all patients starting ART from 2005 to 2019 in eight South African cohorts participating in the International epidemiology Databases to Evaluate AIDS (IeDEA) collaboration. Multivariable logistic regression models were used to determine factors associated with having a viral load measurement within 2 months of a scheduled testing date and having a viral load <400 RNA copies/ml ('viral suppression'). In a sensitivity analysis, missing viral loads were imputed based on patients' clinical and demographic characteristics and outcomes. RESULTS: Viral load tests were scheduled in 603,549 and 77,423 intervals in adults and children, respectively, but test results were recorded in only 40.7% and 41.2%, respectively. The proportion of recorded results suppressed was 85.7% in adults and 72.4% in children. After imputation of missing viral load measurements, viral suppression reduced slightly in adults (85.3%) and increased in children (73.2%). Predictors of virological suppression in adults, which included female sex, older age, higher baseline CD4+ T-cell count and recent testing year, were similar in the main analysis and after imputing missing viral loads. CONCLUSIONS: Although viral load information was frequently missing in the South African setting, estimates of viral suppression and predictors of viral suppression did not change substantially after adjusting for missing data.

Trends in CD4 and viral load testing 2005 to 2018: multi-cohort study of people living with HIV in Southern Africa.

INTRODUCTION: The World Health Organization (WHO) recommends a CD4 cell count before starting antiretroviral therapy (ART) to detect advanced HIV disease, and routine viral load (VL) testing following ART initiation to detect treatment failure. Donor support for CD4 testing has declined to prioritize access to VL monitoring. We examined trends in CD4 and VL testing among adults (≥15 years of age) starting ART in Southern Africa. METHODS: We analysed data from 14 HIV treatment programmes in Lesotho, Malawi, Mozambique, South Africa, Zambia and Zimbabwe in 2005 to 2018. We examined the frequency of CD4 and VL testing, the percentage of adults with CD4 or VL tests, and among those having a test, the percentage starting ART with advanced HIV disease (CD4 count <200 cells/mm3 ) or failing to suppress viral replication (>1000 HIV-RNA copies/mL) after ART initiation. We used mixed effect logistic regression to assess time trends adjusted for age and sex. RESULTS: Among 502,456 adults, the percentage with CD4 testing at ART initiation decreased from a high of 78.1% in 2008 to a low of 38.0% in 2017; the probability declined by 14% each year (odds ratio (OR) 0.86; 95% CI 0.86 to 0.86). Frequency of CD4 testing also declined. The percentage starting ART with advanced HIV disease declined from 83.3% in 2005 to 23.5% in 2018; each year the probability declined by 20% (OR 0.80; 95% CI 0.80 to 0.81). VL testing after starting ART varied; 61.0% of adults in South Africa and 10.7% in Malawi were tested, but fewer than 2% were tested in the other four countries. The probability of VL testing after ART start increased only modestly each year (OR 1.06; 95% CI 1.05 to 1.06). The percentage with unsuppressed VL was 8.6%. There was no evidence of a decrease in unsuppressed VL over time (OR 1.00; 95% CI 0.99 to 1.01). CONCLUSIONS: CD4 cell counting declined over time, including testing at the start of ART, despite the fact that many patients still initiated ART with advanced HIV disease. Without CD4 testing and expanded VL testing many patients with advanced HIV disease and treatment failure may go undetected, threatening the effectiveness of ART in sub-Saharan Africa.

Virologic response to efavirenz-based first-line antiretroviral therapy in children with previous exposure to antiretrovirals to prevent mother-to-child transmission.

Efavirenz-based first-line regimens have been widely used for children ≥3 years of age starting antiretroviral therapy, despite possible resistance with prior exposure to non-nucleoside reverse transcriptase inhibitors for prevention of mother-to-child transmission (PMTCT). We used logistic regression to examine the association between PMTCT exposure and viral failure (VF) defined as two consecutive viral loads (VL)>1000 copies/ml between 6-18 months on ART. Children with previous nevirapine exposure for PMTCT were not at higher risk of VF compared to unexposed children (adjusted Odds Ratio (aOR): 0.79; 95% CI:0.56, 1.11).

What Should We Do When HIV-positive Children Fail First-line Combination Antiretroviral Therapy? A Comparison of 4 ART Management Strategies.

BACKGROUND: Managing virologic failure (VF) in HIV-infected children is especially difficult in resource-limited settings, given limited availability of alternative drugs, concerns around adherence, and the development of HIV resistance mutations. We aimed to evaluate 4 management strategies for children following their first episode of VF by comparing their immunologic and virologic outcomes. METHODS: We included children (< 16 years of age) with VF from 8 International Epidemiologic Database to Evaluate AIDS Southern Africa cohorts, initiating combination antiretroviral therapy (cART) between 2004 and 2010, who followed one of the 4 management strategies: continuing on their failing regimen; switching to a second-line regimen; switching to a holding regimen (either lamivudine monotherapy or other non-cART regimen); discontinuing all ART. We compared the effect of management strategy on the 52-week change in CD4% and log10VL from VF, using inverse probability weighting of marginal structural linear models. RESULTS: Nine hundred eighty-two patients were followed over 54,168 weeks. Relative to remaining on a failing regimen, switching to second-line showed improved immunologic and virologic responses 52 weeks after VF with gains in CD4% of 1.5% (95% confidence interval [CI], 0.2-2.8) and declines in log10VL of -1.4 copies/mL (95% CI, -2.0, -0.8), while switching to holding regimens or discontinuing treatment had worse immunologic (-5.4% (95% CI, -12.1, 1.3) and -5.6% (95% CI, -15.4, 4.1) and virologic outcomes (0.2 (95% CI, -3.6, 4.1) and 0.8 (95% CI, -0.6, 2.1), respectively. CONCLUSIONS: The results provide useful guidance for managing children with VF. Consideration should be given to switching children failing first-line cART to second-line, given the improved virologic and immune responses when compared with other strategies.

Field Evaluation of Performance of Alere and Cepheid Qualitative HIV Assays for Pediatric Point-of-Care Testing in an Academic Hospital in Soweto, South Africa.

Point-of-care (POC) technologies for HIV diagnosis in infants have the potential to overcome logistical challenges that delay treatment initiation and prevent improvements in morbidity and mortality. This study aimed to evaluate the performance of two POC technologies against the current standard-of-care (SOC) laboratory-based assay in South Africa, when operated by nurses in a hospital environment. Children <18 months of age who were treatment naive (excluding prophylaxis) and in whom an HIV PCR test was indicated were eligible for the study. To increase the rate of enrollment of HIV PCR-positive children, HIV-exposed neonates at high risk of mother-to-child transmission and children requiring confirmatory HIV testing were preferentially enrolled. The two POC technologies demonstrated excellent concordance, with 315 (97.8%) results consistent with the SOC result. The POC technologies yielded 102 positive and 220 negative tests each. The SOC assay had 101 positive, 214 negative, 4 indeterminate, 1 invalid, and 2 specimen-rejected results. To include the indeterminate results in sensitivity/specificity calculations, a sensitivity analysis was performed, which yielded a simulated sensitivity of 0.9904 (interquartile range [IQR], 0.9808 to 0.9904) and a specificity of 0.9954 (IQR, 0.9954 to 1.0). This study confirmed that both POC technologies can be successfully used outside the laboratory environment to yield precise sensitivity/specificity values for pediatric, including neonatal, HIV testing.

Immunogenicity of 13-valent pneumococcal conjugate vaccine among children with underlying medical conditions.

BACKGROUND: Streptococcus pneumoniae is a leading cause of vaccine-preventable disease in children under 5years. Immunocompromised children and those with underlying diseases are at increased risk of severe complications from vaccine-preventable infections. We studied the humoral immune response to the 13-valent pneumococcal conjugate vaccine (PCV13) in children with HIV-infection, kidney or lung disease and compared this to the response in healthy control children. METHODS: Children aged 12-71months with underlying conditions including HIV-infection and those with kidney and lung diseases (at-risk children), and a healthy control group were vaccinated with PCV13. The at-risk children received two doses of PCV13 and the controls received one dose. Serotype-specific antibodies for all PCV13 serotypes were measured by a luminex-based enzyme immunoassay at baseline and post-vaccination. RESULTS: After the first PCV13 dose, the fold-increase in serotype-specific antibody geometric mean concentrations (GMCs) from baseline and the percentage of participants with ≥4-fold-increase in antibody concentrations was similar between the control and at-risk children. GMCs were, however, lower for three of the 13 serotypes in HIV-infected children, higher for serotype 6B in children with kidney disease and higher for serotypes 6B and 14 in children with lung disease. After second vaccine dose HIV-infected children had an increase in GMCs from post-first dose for nine serotypes but the percentage of participants with ≥4-fold-increase from baseline was similar post-second dose compared to post-first dose except for serotypes 6A and 19F. In children with kidney or lung diseases the immune responses after second vaccine dose were similar to post-first dose. Attenuated responses were observed for serotypes 3 and 19A in all study-groups, which was especially pronounced in the at-risk groups. CONCLUSION: All study-groups mounted an immune response to PCV13, with the at-risk groups having responses that were mostly similar to the control children.

Predictors of loss to follow-up among children in the first and second years of antiretroviral treatment in Johannesburg, South Africa.

BACKGROUND: Ninety percent of the world's 2.1 million HIV-infected children live in sub-Saharan Africa, and 2.5% of South African children live with HIV. As HIV care and treatment programmes are scaled-up, a rise in loss to follow-up (LTFU) has been observed. OBJECTIVE: The aim of the study was to determine the rate of LTFU in children receiving antiretroviral treatment (ART) and to identify baseline characteristics associated with LTFU in the first year of treatment. We also explored the effect of patient characteristics at 12 months treatment on LTFU in the second year. METHODS: The study is an analysis of prospectively collected routine data of HIV-infected children at the Harriet Shezi Children's Clinic (HSCC) in Soweto, Johannesburg. Cox proportional hazards models were fitted to investigate associations between baseline characteristics and 12-month characteristics with LTFU in the first and second year on ART, respectively. RESULTS: The cumulative probability of LTFU at 12 months was 7.3% (95% CI 7.1-8.8). In the first 12 months on ART, independent predictors of LTFU were age <1 year at initiation, recent year of ART start, mother as a primary caregiver, and being underweight (WAZ ≤ -2). Among children still on treatment at 1 year from ART initiation, characteristics that predicted LTFU within the second year were recent year of ART start, mother as a primary caregiver, being underweight (WAZ ≤ -2), and low CD4 cell percentage. CONCLUSIONS: There are similarities between the known predictors of death and the predictors of LTFU in the first and second years of ART. Knowing the vital status of children is important to determine LTFU. Although HIV-positive children cared for by their mothers appear to be at greater risk of becoming LTFU, further research is needed to explore the challenges faced by mothers and other caregivers and their impact on long-term HIV care. There is also a need to investigate the effects of differential access to ART between mothers and children and its impact on ART outcomes in children.