Underdosing of antiretrovirals in UK and Irish children with HIV as an example of problems in prescribing medicines to children, 1997-2005: cohort study

Drug resistance profiles and influencing factors among HIV-infected children and adolescents receiving long-term ART: a multicentre observational study in China

OBJECTIVES

To analyse the characteristics and determinants of drug resistance mutations (DRMs) in HIV-infected children and adolescents on long-term ART in China.

METHODS

An observational cohort study was conducted in five centres. All participants younger than 15 years at ART initiation were screened, and those identified as having virological failure (VF) with viral load (VL) ≥ 400 copies/mL were included for genotypic resistance testing. Logistic regression analysis was performed and the accumulation of major mutations was analysed in a subgroup of resistant individuals with complete VL results since HIV diagnosis.

RESULTS

Among 562 eligible participants, protease and RT regions were successfully amplified for 93 who failed treatment with a median of 10.0 years ART. Sixty-eight (73.1%) harboured ≥1 major mutations. NRTI, NNRTI and dual-class resistance accounted for 48.4%, 63.4% and 38.7%, respectively. Only 3.2% were resistant to PIs. Age at ART initiation [adjusted OR (aOR) = 0.813, 95% CI 0.690-0.957], subtype B (aOR = 4.378, 95% CI 1.414-13.560) and an initial NNRTI-based regimen (aOR = 3.331, 95% CI 1.180-9.402) were independently associated with DRMs. Among 40 resistant participants with additional VL data, 55.0% had continued VF on a suboptimal regimen and the estimated duration of VF was positively correlated with the total number of major mutations (r = 0.504, P = 0.001).

CONCLUSIONS

The development of DRMs was common in children and adolescents receiving long-term treatment, and continued VF was prevalent in those with resistance. Timely genotypic testing and new child-friendly formulations are therefore urgently required.

Off-label use of combined antiretroviral therapy, analysis of data collected by the Italian Register for HIV-1 infection in paediatrics in a large cohort of children

BACKGROUND

Early start of highly active antiretroviral therapy (HAART) in perinatally HIV-1 infected children is the optimal strategy to prevent immunological and clinical deterioration. To date, according to EMA, only 35% of antiretroviral drugs are licenced in children < 2 years of age and 60% in those aged 2-12 years, due to the lack of adequate paediatric clinical studies on pharmacokinetics, pharmacodynamics and drug safety in children.

METHODS

An observational retrospective study investigating the rate and the outcomes of off-label prescription of HAART was conducted on 225 perinatally HIV-1 infected children enrolled in the Italian Register for HIV Infection in Children and followed-up from 2001 to 2018.

RESULTS

22.2% (50/225) of included children were receiving an off-label HAART regimen at last check. Only 26% (13/50) of off-label children had an undetectable viral load (VL) before the commencing of the regimen and the 52.0% (26/50) had a CD4 + T lymphocyte percentage > 25%. At last check, during the off label regimen, the 80% (40/50) of patients had an undetectable VL, and 90% (45/50) of them displayed CD4 + T lymphocyte percentage > 25%. The most widely used off-label drugs were: dolutegravir/abacavir/lamivudine (16%; 8/50), emtricitbine/tenofovir disoproxil (22%; 11/50), lopinavir/ritonavir (20%; 10/50) and elvitegravir/cobicistat/emtricitabine/ tenofovir alafenamide (10%; 10/50). At logistic regression analysis, detectable VL before starting the current HAART regimen was a risk factor for receiving an off-label therapy (OR: 2.41; 95% CI 1.13-5.19; p = 0.024). Moreover, children < 2 years of age were at increased risk for receiving off-label HAART with respect to older children (OR: 3.24; 95% CI 1063-7.3; p = 0.001). Even if our safety data regarding off-label regimens where poor, no adverse event was reported.

CONCLUSION

The prescription of an off-label HAART regimen in perinatally HIV-1 infected children was common, in particular in children with detectable VL despite previous HAART and in younger children, especially those receiving their first regimen. Our data suggest similar proportions of virological and immunological successes at last check among children receiving off-label or on-label HAART. Larger studies are needed to better clarify efficacy and safety of off-label HAART regimens in children, in order to allow the enlargement of on-label prescription in children.

The DIANA Study: Continued Access to Darunavir/Ritonavir (DRV/r) and Long-Term Safety Follow-Up in HIV-1-Infected Pediatric Patients Aged 3 to < 18 Years

INTRODUCTION

Darunavir is a human immunodeficiency virus type 1 (HIV-1) protease inhibitor boosted with ritonavir (DRV/r) or cobicistat.

OBJECTIVE

This study provided continued access to DRV/r and assessed long-term safety in patients aged 3 to < 18 years.

METHODS

Patients who had completed treatment in the DELPHI (TMC114-C212), DIONE (TMC114-TiDP29-C230), or ARIEL (TMC114-TiDP29-C228) studies were eligible to participate if they derived benefit from using DRV/r in countries where it was not available to them. DRV/r dosing was continued based on original study protocols. Only safety data were collected. Reportable adverse events (AEs) included AEs considered at least possibly related to treatment with DRV/r, AEs leading to discontinuation or treatment interruption, and serious AEs (SAEs).

RESULTS

Forty-six patients rolled over to this study and received at least one dose of DRV/r. Median duration of DRV/r intake was 4.2 years. Overall, 15/46 patients experienced one or more reportable AEs, 10/46 patients experienced one or more grade 3 or 4 AEs, and 12/46 patients experienced one or more SAEs. The most common grade 3 or 4 and SAEs were pneumonia (3/46) and asthma (2/46). Only one AE (grade 1 lipoatrophy) was considered probably related to DRV/r (DIONE, n = 1). Overall, 3/46 patients experienced an HIV-related AE (grade 3 pneumonia SAE; grade 2 tuberculosis SAE, and grade 2 lipoatrophy AE), none of which were considered related to DRV/r or led to study discontinuation. Two AEs leading to discontinuation were pregnancies.

CONCLUSION

These long-term safety results continue to support DRV/r as a valuable therapeutic option for the treatment of HIV-1 infection in pediatric patients aged ≥ 3 years.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT01138605/EudraCT number: 2009-017013-29; first submitted 8 April 2010.

Drug resistance in HIV-infected children living in rural South Africa: Implications of an antiretroviral therapy initiated during the first year of life

INTRODUCTION

Management of antiretroviral-drug resistance in HIV-infected children is a global health concern. We compared the long-term virological outcomes of two cohorts of children living in a rural setting of South Africa. The first cohort initiated treatment before one year and the second after two years of age. The aim of this study was to describe the long-term consequences of early treatment initiation in terms of viral load and drug-resistance.

METHODS

This retrospective study was conducted at the Edendale Hospital located in a peri-urban area of KwaZulu-Natal. Children were included during their planned appointment. Drug resistance was assessed genotypically on proviral DNA.

RESULTS

From the 161 children included in this study, 93 samples were successfully genotyped. Both cohorts had comparable viral loads, but children treated early more often presented NRTI or NNRTI mutations, while there was no difference for PI mutations rates.

CONCLUSIONS

Treatment was highly effective when comparing virological outcomes in both early- and late-treated cohorts. The persistence of NNRTI mutations could lead to treatment failures in children older than 3 years initiating their therapy with a NNRTI, or for those switching from a PI to NNRTI based regimen. The accumulation of NRTI mutations may lead to a functional PI monotherapy and consequently to viral escape. To promote access to HIV genotyping in resource-limited settings is challenging but essential to avoid inappropriate therapy switches in case of virological failure, and to adapt national treatment guidelines in line with the epidemiology of resistance.

Off-label Use in Ambulatory Paediatric Clinics in a Central South African Hospital

AIM

The aim of this article was to determine off-label (OL) use in paediatric ambulatory clinics in a South African central hospital.

PATIENTS AND METHODS

OL medicine events were documented in three paediatric clinics (general, highly specialized and dedicated HIV paediatric clinics) at Tygerberg Hospital, South Africa, and analysed according to South African medicine registration information.

RESULTS

There were 2167 medicine events for 658 children. Mean age was 5.6 years (interquartile range 1.8-8.8). There were 123 OL medicine events (6%). Extemporaneous OL use was most common (n = 58, 47%), followed by weight (n = 45, 37%) and lack of paediatric data (n = 38, 31%). Of note was OL use for weight for general paediatrics (n = 32, 78%, p < 0.001), lack of appropriate paediatric data for highly specialized paediatrics (n = 26, 61%, p = 0.004) and extemporaneous use for HIV-infected children (n = 34, 87%, p < 0.001), with significant less OL use for HIV-infected children (p = 0.009).

CONCLUSIONS

Of note is significant extemporaneous OL use in HIV-infected children.

Evaluation of weight-based prescription of antiretroviral therapy in children

Objectives

The aim of the study was to investigate the extent of and factors associated with incorrect dosing of antiretroviral therapy (ART) in HIV‐infected children in Harare, Zimbabwe.

Methods

All children aged 0–10 years and children aged 11–17 years who weighed < 35 kg and taking ART were recruited from the paediatric HIV clinic at Harare Hospital. Their current doses of ART drugs were compared against doses recommended by the national guidelines.

Results

Among 309 children recruited [55% male; median age 7 years (interquartile range (IQR) 5–10 years)], the median CD4 count was 899 cells/μL and the median duration of their current ART regimen was 11.2 months (IQR 4.9–17.1 months). Overall, 110 (35.6%) children were prescribed incorrect doses of at least one drug component within their ART regimen; 64 (20.7%) under‐dosed and 49 (15.9%) over‐dosed on at least one drug. Children receiving a higher than recommended dose of at least one drug were younger compared with correctly dosed children (median 6 versus 7 years, respectively; P = 0.001), had been on their current ART regimen for a shorter time (median 7.2 versus 13 months, respectively; P = 0.003) and were less likely to be receiving a three‐drug fixed‐dose combination (FDC; 42.9 versus 63.3%, respectively; P = 0.009). Those who were under‐dosed were also less likely to be on a three‐drug FDC (25 versus 63.3%, respectively; P < 0.001).

Conclusions

Over a third of children were prescribed incorrect doses of ART. Children taking triple‐drug FDCs were likely to be correctly dosed. Our study highlights the importance of weight monitoring at each clinical contact, training of health care providers on paediatric drug dosing and the need for wider availability of FDCs for children.

Scale-up of Kenya's national HIV viral load program: Findings and lessons learned

Objectives

Kenya is one of the first African countries to scale up a national HIV viral load monitoring program. We sought to assess program scale up using the national database and identify areas for systems strengthening.

Methods

Data from January 2012 to March 2016 were extracted from Kenya’s national viral load database. Characteristics of 1,108,356 tests were assessed over time, including reason for testing, turnaround times, test results, treatment regimens, and socio-demographic information.

Results

The number of facilities offering viral load testing increased to ~2,000 with >40,000 tests being conducted per month by 2016. By March 2016, most (84.2%) tests were conducted for routine monitoring purposes and the turnaround time from facility-level sample collection to result dispatch from the lab was 21(24) [median (IQR)] days. Although the proportions of repeat viral load tests increased over time, the volumes were lower than expected. Elevated viral load was much more common in pediatric and adolescent patients (0-<3 years: 43.1%, 3-<10 years: 34.5%, 10-<20 years: 36.6%) than in adults (30-<60 years: 13.3%; p<0.001).

Conclusions

Coverage of viral load testing dramatically increased in Kenya to >50% of patients on antiretroviral therapy (ART) by early 2016 and represents a relatively efficient laboratory system. However, strengthening of patient tracking mechanisms and viral load result utilization may be necessary to further improve the system. Additional focus is needed on paediatric/adolescent patients to improve viral suppression in these groups. Kenya’s national viral load database has demonstrated its usefulness in assessing laboratory programs, tracking trends in patient characteristics, monitoring scale-up of new policies and programs, and identifying problem areas for further investigation.

The case for viral load testing in adolescents in resource-limited settings

INTRODUCTION

The success of HIV treatment programmes globally has resulted in children with perinatally acquired HIV reaching adolescence in large numbers. The number of adolescents living with HIV is growing further due to persisting high HIV incidence rates among adolescents in low- and middle-income settings, particularly in sub-Saharan Africa. Although expanding access to HIV viral load monitoring is necessary to achieve the 90-90-90 targets across the HIV care continuum, implementation is incomplete. We discuss the rationale for prioritizing viral load monitoring among adolescents and the associated challenges.

DISCUSSION

Adolescents with HIV are a complex group to treat successfully due to extensive exposure to antiretroviral therapy for those with perinatally acquired HIV and the challenges in sustained medication adherence in this age group. Given the high risk of treatment failure among adolescents and the limited drug regimens available in limited resource settings, HIV viral load monitoring in adolescents could prevent unnecessary and costly switches to second-line therapy in virologically suppressed adolescents. Because adolescents living with HIV may be heavily treatment experienced, have suboptimal treatment adherence, or may be on second or even third-line therapy, viral load testing would allow clinicians to make informed decisions about increased counselling and support for adolescents together with the need to maintain or switch therapeutic regimens.

CONCLUSIONS

Given scarce resources, prioritization of viral load testing among groups with a high risk of virological failure may be required. Adolescents have disproportionately high rates of virological failure, and targeting this age group for viral load monitoring may provide valuable lessons to inform broader scale-up.

Clinical outcomes in children and adolescents initiating antiretroviral therapy in decentralized healthcare settings in Zimbabwe

INTRODUCTION

Decentralized HIV care for adults does not appear to compromise clinical outcomes. HIV care for children poses additional clinical and social complexities. We conducted a prospective cohort study to investigate clinical outcomes in children aged 6-15 years who registered for HIV care at seven primary healthcare clinics (PHCs) in Harare, Zimbabwe.

METHODS

Participants were recruited between January 2013 and December 2014 and followed for 18 months. Rates of and reasons for mortality, hospitalization and unscheduled PHC attendances were ascertained. Cox proportional modelling was used to determine the hazard of death, unscheduled attendances and hospitalization.

RESULTS

We recruited 385 participants, median age 11 years (IQR: 9-13) and 52% were female. The median CD4 count was 375 cells/mm3 (IQR: 215-599) and 77% commenced ART over the study period, with 64% of those who had viral load measured achieving an HIV viral load <400 copies/ml. At 18 months, 4% of those who started ART vs. 24% of those who remained ART-naïve were lost-to-follow-up (p < 0.001). Hospitalization and mortality rates were low (8.14/100 person-years (pyrs) and 2.86/100 pyrs, respectively). There was a high rate of unscheduled PHC attendances (34.94/100 pyrs), but only 7% resulted in hospitalization. Respiratory disease was the major cause of hospitalization, unscheduled attendances and death. CD4 count <350cells/mm3 was a risk factor for hospitalization (aHR 3.6 (95%CI 1.6-8.2)).

CONCLUSIONS

Despite only 64% of participants achieving virological suppression, clinical outcomes were good and high rates of retention in care were observed. This demonstrates that in an era moving towards differentiated care in addition to implementation of universal treatment, decentralized HIV care for children is achievable. Interventions to improve adherence in this age-group are urgently needed.

K. HK, Ramachandran G, Shet A. Sub-therapeutic nevirapine concentration during antiretroviral treatment initiation among children living with HIV: Implications for therapeutic drug monitoring

Nevirapine, a component of antiretroviral therapy (ART) in resource-limited settings, known for auto-induction of metabolism, is initiated at half therapeutic dose until day 14 (‘lead-in period’), and subsequently escalated to full dose. However, studies have shown that this dosing strategy based on adult studies may not be appropriate in children, given that younger children have higher drug clearance rates. In this prospective cohort study, we studied trough plasma nevirapine levels by high performance liquid chromatography (HPLC) at days 7, 14 (lead-in period) and 28 (full dose period) after ART initiation amongst HIV-1 infected children initiating nevirapine-based ART in southern India. Among the 20 children (50% male, median age 9 years) included in the study, sub-therapeutic trough plasma nevirapine concentration (<4μg/ml) was seen in 65% (13/20) of children during the lead-in period within two weeks of ART initiation and among 10% of children at 4 weeks during full-dose nevirapine. Adherence was documented as ≥95% in all children by both caregiver self-report and pill count. Median nevirapine concentrations achieved at week 1 was 4.8 μg/ml, significantly lower than 8 μg/ml, the concentration achieved at week 4 (p = 0.034). Virological failure at one year of ART was observed in six children, and was not associated with median nevirapine concentration achieved during week 1, 2 or 4. We conclude that the dose escalation strategy currently practiced among young children living with HIV-1 resulted in significant subtherapeutic nevirapine concentration (≤4μg/ml) during the lead-in period. We call for a closer look at pediatric-focused dosing strategies for nevirapine initiation in young children. Further studies to establish age-appropriate threshold nevirapine concentration are warranted in young children to corroborate the role of therapeutic drug monitoring in predicting virological outcome.

Antifungal stewardship considerations for adults and pediatrics

Antifungal stewardship refers to coordinated interventions to monitor and direct the appropriate use of antifungal agents in order to achieve the best clinical outcomes and minimize selective pressure and adverse events. Antifungal utilization has steadily risen over time in concert with the increase in number of immunocompromised adults and children at risk for invasive fungal infections (IFI). Challenges in diagnosing IFI often lead to delays in treatment and poorer outcomes. There are also emerging data linking prior antifungal exposure and suboptimal dosing to the emergence of antifungal resistance, particularly for Candida. Antimicrobial stewardship programs can take a multi-pronged bundle approach to ensure suitable prescribing of antifungals via post-prescription review and feedback and/or prior authorization. Institutional guidelines can also be developed to guide diagnostic testing in at-risk populations; appropriate choice, dose, and duration of antifungal agent; therapeutic drug monitoring; and opportunities for de-escalation and intravenous-to-oral conversion.

Pharmacokinetics and Pharmacokinetic/Pharmacodynamic Relationships of Etravirine in HIV-1-Infected, Treatment-Experienced Children and Adolescents in PIANO

PIANO (NCT00665847) investigated etravirine pharmacokinetics, efficacy, and safety in children and adolescents. Treatment-experienced, HIV-1-infected patients (≥6 to <18 years) received etravirine 5.2 mg/kg twice daily (maximum 200 mg twice daily) plus background antiretrovirals. A population pharmacokinetic model was developed, and etravirine C_0h and AUC_0-12h were estimated. Relationships among intrinsic/extrinsic factors and etravirine pharmacokinetics and pharmacokinetics with pharmacodynamics were assessed. The best model describing etravirine pharmacokinetics consisted of a single compartment with sequential zero- and first-order absorption following a lag time. Interindividual variability terms were included on clearance (CL/F) and the first-order input rate constant (KA). The final model estimates (coefficient of variation, %) for CL/F and KA were 46.3 (11) L/h and 1.07 (34) h^-1 , respectively. Overall, median (range) estimated etravirine C_0h and AUC_0-12h were 287 (2-2276) ng/mL and 4560 (62-28,865) ng · h/mL, respectively. Exposure was slightly lower in adolescents vs children. Sex and adherence did not affect etravirine pharmacokinetics. Factors significantly affecting etravirine exposure were body weight (higher with lower weight), race (lower in Asians than in white or black patients), and the use of certain HIV protease inhibitors. Virologic response (<50 copies/mL at week 48) was lower in the lowest etravirine AUC_0-12h quartile vs the upper 3 quartiles (41% vs 67% to 76%). Rash occurred more frequently in the highest quartile than in the lower 3 quartiles (52% versus 8% to 20%). Etravirine 5.2 mg/kg twice daily in treatment-experienced, HIV-1-infected children and adolescents provides comparable exposure to that in adults receiving etravirine 200 mg twice daily and is the recommended dose for children and adolescents.

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.

Development of HIV drug resistance and therapeutic failure in children and adolescents in rural Tanzania: an emerging public health concern

Objective:

To investigate the prevalence and determinants of virologic failure and acquired drug resistance-associated mutations (DRMs) in HIV-infected children and adolescents in rural Tanzania.

Design:

Prospective cohort study with cross-sectional analysis.

Methods:

All children 18 years or less attending the paediatric HIV Clinic of Ifakara and on antiretroviral therapy (ART) for at least 12 months were enrolled. Participants with virologic failure were tested for HIV-DRM. Pre-ART samples were used to discriminate acquired and transmitted resistances. Multivariate logistic regression analysis identified factors associated with virologic failure and the acquisition of HIV-DRM.

Results:

Among 213 children on ART for a median of 4.3 years, 25.4% failed virologically. ART-associated DRM were identified in 90%, with multiclass resistances in 79%. Pre-ART data suggested that more than 85% had acquired key mutations during treatment. Suboptimal adherence [odds ratio (OR) = 3.90; 95% confidence interval (CI) 1.11–13.68], female sex (aOR = 2.57; 95% CI 1.03–6.45), and current nonnucleoside reverse transcriptase inhibitor-based ART (aOR = 7.32; 95% CI 1.51–35.46 compared with protease inhibitor-based) independently increased the odds of virologic failure. CD4⁺ T-cell percentage (aOR = 0.20; 0.10–0.40 per additional 10%) and older age at ART initiation (aOR = 0.84 per additional year of age; 95% CI 0.73–0.97) were protective (also in predicting acquired HIV-DRM). At the time of virologic failure, less than 5% of the children fulfilled the WHO criteria for immunologic failure.

Conclusion:

Virologic failure rates in children and adolescents were high, with the majority of ART-failing children harbouring HIV-DRM. The WHO criteria for immunologic treatment failure yielded an unacceptably low sensitivity. Viral load monitoring is urgently needed to maintain future treatment options for the millions of African children living with HIV.

Rilpivirine as a Treatment for HIV-infected Antiretroviral-naïve Adolescents: Week 48 Safety, Efficacy, Virology and Pharmacokinetics

BACKGROUND

Rilpivirine 25 mg qd yields similar exposure in adolescents and adults (Pediatric study in Adolescents Investigating a New NNRTI TMC278 [PAINT] Cohort 1, Part 1). We report rilpivirine safety, efficacy, virology and pharmacokinetics in adolescents during 48 weeks of treatment (Cohort 1, Part 2).

METHODS

PAINT (NCT00799864) is a phase II, ongoing, open-label, single-arm trial of rilpivirine plus 2 investigator-selected nucleoside/nucleotide reverse-transcriptase inhibitors. Cohort 1 of PAINT includes treatment-naïve HIV-1-infected adolescents (≥12 to <18 years). Following approval in adults and after Part 1a in Cohort 1, enrollment was restricted to screening viral load (VL) ≤100,000 copies/mL.

RESULTS

Overall, 20 (56%) of 36 patients were women, 18 (50%) were aged ≥12 to <15 years, 32 (89%) were Black or African American, mostly from South Africa or Uganda, and 28 (78%) had baseline VL ≤100,000 copies/mL. At week 48, adverse events considered possibly related to treatment occurred in 13 (36%) patients, mostly (excluding investigations) somnolence (n = 5, 14%) and nausea (n = 2, 6%). Most adverse events were grade 1 or 2, and 7 (19%) patients had grade 3 or 4 adverse events. Week 48 virologic response (VL <50 copies/mL, time-to-loss-of-virologic-response) was achieved in 26 of the 36 (72%) patients: 22 of the 28 (79%) with baseline VL ≤100,000 copies/mL and 4 of the 8 (50%) with baseline VL >100,000 copies/mL. Median (range) CD4 count increased by 184 (-135 to 740) cells/mm at week 48. Eight patients experienced virologic failure, including 5 who developed rilpivirine resistance-associated mutations, mostly E138K, K101E and M230L. Mean (standard deviation) rilpivirine area-under-the-concentration-time curve from 0 to 24 hours (AUC24h and C0h) were 2391 (991) ng·h/mL and 83.5 (38.7) ng/mL, respectively.

CONCLUSIONS

Rilpivirine safety, virologic and pharmacokinetic profiles were similar in treatment-naïve HIV-1-infected adolescents and adults, supporting use of rilpivirine 25 mg qd, plus other antiretrovirals, in treatment-naïve adolescents with VL ≤100,000 copies/mL at treatment initiation.

Use of Integrase Inhibitors in HIV-Infected Children and Adolescents

Resistance to antiretroviral drugs is an increasingly prevalent challenge affecting both the adult and pediatric HIV-infected populations. Though data on the safety, pharmacokinetics, and efficacy of newer antiretroviral agents in children typically lags behind adult data, newer agents are becoming available for use in HIV-infected children who are failing to respond to or are experiencing toxicities with traditional antiretroviral regimens. Integrase strand transfer inhibitors are one such new class of antiretrovirals. Raltegravir has been US Food and Drug Administration (FDA) approved for use in patients over the age of 4 weeks. Elvitegravir is a second member of this class, and has the potential for use in children but does not yet have a Pediatric FDA indication. Dolutegravir, a second-generation integrase inhibitor, is approved for those older than 12 years. This review summarizes the use of integrase inhibitors in children and adolescents, and highlights the results of recent clinical trials.

Off-label use of rilpivirine in combination with emtricitabine and tenofovir in HIV-1-infected pediatric patients: A multicenter study

To assess the safety and efficacy of rilpivirine in combination with emtricitabine and tenofovir (RPV/FTC/TDF) as a once-daily single-tablet regimen (STR) in HIV-1-infected children and adolescents we performed a multicenter case series study of HIV-1-infected patients. Inclusion criteria were initiation of therapy with RPV/FTC/TDF before the age of 18. Patients were divided into undetectable viral load (uVL) group, HIV-1 RNA < 20 copies/mL on stable combined antiretroviral therapy (cART), and detectable viral load (dVL) group, HIV-1 RNA ≥ 20 copies/mL at RPV/FTC/TDF initiation. Patients were monitored from the date of RPV/FTC/TDF initiation until June 30, 2015, RPV/FTC/TDF discontinuation or failure to follow-up. Seventeen patients (8 in uVL and 9 in dVL group) with age between 11.6 and 17.6 were included. Reasons for switching were toxicity (n = 4) and simplification (n = 4) in uVL; viral failure (n = 8) and cART initiation (n = 1) in the dVL group. After a median follow-up of 90 (uVL) and 40 weeks (dVL), 7/8 (86%) patients maintained and 8/9 (89%) achieved and maintained HIV-1 suppression. Median CD4 count increased from 542 to 780/μL (uVL, P = 0.069) and 480 to 830/μL (dVL, P = 0.051). Five patients (2 in uVL and 3 in dVL) improved their immunological status from moderate to no immunosuppression. Serum lipid profiles improved in both groups; cholesterol dropped significantly in the dVL group (P = 0.008). Grade 1 laboratory adverse events (AEs) were observed in 3 patients. No clinical AEs occurred. Adherence was complete in 9 patients (5 in uVL and 4 in dVL); 1 adolescent interrupted treatment. Once-daily STR with RPV/FTC/TDF may be a safe and effective choice in selected HIV-1-infected adolescents and children.

High rate of lymphoma among a UK cohort of adolescents with vertically acquired HIV-1 infection transitioning to adult care in the era of antiretroviral therapy

Among an inner London UK cohort of 147 adolescents transitioning from paediatric into adult care between 2007 and 2015, a new diagnosis of lymphoma was made in five patients; incidence rate = 0.425/100 person-years (95% confidence interval = 0.424-0.426). Previously described risk factors, including low nadir CD4 cell count and ongoing HIV-1 viraemia, appeared to be important. These data suggest that careful surveillance and a low threshold for investigating relevant symptoms continue to be essential for such patients.

A Case Series of Acquired Drug Resistance-Associated Mutations in Human Immunodeficiency Virus-Infected Children: An Emerging Public Health Concern in Rural Africa

The acquisition of drug-resistance mutations among African children living with in human immunodeficiency virus on antiretroviral treatment has been scarcely reported. This threatens the overall success of antiretroviral programs and the clinical outcomes of children in care. We present a well characterized series of children from rural Tanzania with acquired drug-resistance mutations to contribute to the better understanding of this emerging public health concern.

The physical and psychological effects of HIV infection and its treatment on perinatally HIV-infected children

INTRODUCTION

As highly active antiretroviral therapy (HAART) transforms human immunodeficiency virus (HIV) into a manageable chronic disease, new challenges are emerging in treating children born with HIV, including a number of risks to their physical and psychological health due to HIV infection and its lifelong treatment.

METHODS

We conducted a literature review to evaluate the evidence on the physical and psychological effects of perinatal HIV (PHIV+) infection and its treatment in the era of HAART, including major chronic comorbidities.

RESULTS AND DISCUSSION

Perinatally infected children face concerning levels of treatment failure and drug resistance, which may hamper their long-term treatment and result in more significant comorbidities. Physical complications from PHIV+ infection and treatment potentially affect all major organ systems. Although treatment with antiretroviral (ARV) therapy has reduced incidence of severe neurocognitive diseases like HIV encephalopathy, perinatally infected children may experience less severe neurocognitive complications related to HIV disease and ARV neurotoxicity. Major metabolic complications include dyslipidaemia and insulin resistance, complications that are associated with both HIV infection and several ARV agents and may significantly affect cardiovascular disease risk with age. Bone abnormalities, particularly amongst children treated with tenofovir, are a concern for perinatally infected children who may be at higher risk for bone fractures and osteoporosis. In many studies, rates of anaemia are significantly higher for HIV-infected children. Renal failure is a significant complication and cause of death amongst perinatally infected children, while new data on sexual and reproductive health suggest that sexually transmitted infections and birth complications may be additional concerns for perinatally infected children in adolescence. Finally, perinatally infected children may face psychological challenges, including higher rates of mental health and behavioural disorders. Existing studies have significant methodological limitations, including small sample sizes, inappropriate control groups and heterogeneous definitions, to name a few.

CONCLUSIONS

Success in treating perinatally HIV-infected children and better understanding of the physical and psychological implications of lifelong HIV infection require that we address a new set of challenges for children. A better understanding of these challenges will guide care providers, researchers and policymakers towards more effective HIV care management for perinatally infected children and their transition to adulthood.

Nevirapine Resistance in Previously Nevirapine-Unexposed HIV-1-Infected Kenyan Infants Initiating Early Antiretroviral Therapy

Nevirapine (NVP) resistance occurs frequently in infants following NVP use in prevention of mother-to-child transmission (PMTCT) regimens. However, among previously NVP-unexposed infants treated with NVP-antiretroviral therapy (ART), the development and impact of NVP resistance have not been well characterized. In a prospective clinical trial providing early ART to HIV-infected infants <5 months of age in Kenya (OPH03 study), we followed NVP-unexposed infants who initiated NVP-ART for 12 months. Viral loads were assessed and resistance determined using a population-based genotypic resistance assay. Of 99 infants screened, 33 had no prior NVP exposure, 22 of whom were initiated on NVP-ART. Among 19 infants with follow-up, seven (37%) infants developed resistance: one at 3 months and six at 6 months after ART initiation. The cumulative probability of NVP resistance was 5.9% at 3 months and 43.5% at 6 months. Baseline HIV RNA levels (p=0.7) and other characteristics were not associated with developing resistance. Post-ART, higher virus levels at visits preceding the detection of resistance were significantly associated with increased detection of resistance (p=0.004). Virus levels after 6 and 12 months of ART were significantly higher in infants with resistance than those without (p=0.007, p=0.030, respectively). Among infants without previous NVP exposure, development of NVP resistance was frequent and was associated with virologic failure during the first year of ART. Earlier development of NVP resistance in infants than in adults initiating NVP-ART may be due to longer viremia following ART or inadequate NVP levels resulting from NVP lead-in dosing. The development of NVP resistance may, in part, explain the superiority of protease inhibitor-based ART in infants.

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.

Model-Based Once-Daily Darunavir/Ritonavir Dosing Recommendations in Pediatric HIV-1-Infected Patients Aged ≥3 to <12 Years

An existing population pharmacokinetic model of darunavir in adults was updated using pediatric data from two studies evaluating weight-based, once-daily dosing of darunavir/ritonavir (ARIEL, NCT00919854 and DIONE, NCT00915655). The model was then used to provide once-daily dosing recommendations for darunavir/ritonavir in pediatric patients aged ≥3 to <12 years. The final model comprised two compartments with first-order absorption and apparent clearance dependent on the concentration of α1-acid glycoprotein. The recommended darunavir/ritonavir once-daily dosing regimens in children aged ≥3 to <12 years are: 35/7 mg/kg from 10 to <15 kg, 600/100 mg from 15 to <30 kg, 675/100 mg from 30 to <40 kg, and 800/100 mg for ≥40 kg. These doses should result in exposures similar to the adult exposure after treatment with darunavir/ritonavir 800/100 mg once daily, while minimizing pill burden and allowing a switch from suspension to tablet(s) as early as possible.

Description and consequences of prescribing off-label antiretrovirals in the Madrid Cohort of HIV-infected children over a quarter of a century (1988-2012)

BACKGROUND

Licensing data for paediatric dosing is often sparse and subsequent studies may result in changes to recommended doses. We measured the extent and consequences of off-label antiretroviral (ARV) use in an HIV-infected paediatric cohort.

METHODS

In this multicentre cohort study involving 318 HIV-infected children and adolescents from the Madrid Cohort, all off-label prescriptions from March 1988 to March 2012 were recorded from the clinical records. The reasons for prescribing ARV off-label, the side effects and the consequences of incorrect dosing of ARVs are discussed.

RESULTS

Among the 318 patients of the cohort, 221 (69%) received off-label ARVs according to EMA licensing at the time of prescription, representing 23% (540) of the 2,353 prescribed ARVs. The main reason for starting an off-label drug was treatment failure. Adverse events led to treatment discontinuation in 12% of the prescriptions. Problems taking the drug led to withdrawal in 5%, more likely when formulation was not suitable for age (P<0.05). Up to 10% were overdosed and 10% underdosed, defined as 25% above or below the current recommended dose, respectively. Treatment failure occurred significantly more frequently among underdosed compared to overdosed patients (50% versus 26%; P<0.05).

CONCLUSIONS

Off-label use of ARVs was common in our HIV-1 paediatric patients. Adverse events were common but rarely led to withdrawal. Suitable formulation is important in younger children. Pharmacokinetic studies are needed as frequent incorrect dosing may occur when prescribing off-label and underdosing may lead to treatment failure.

Safety and efficacy of darunavir/ritonavir in treatment-experienced pediatric patients: week 48 results of the ARIEL trial

BACKGROUND

ARIEL (Darunavir in treatment-experienced pediatric population) was a phase II, open-label study assessing safety and antiviral activity of darunavir/ritonavir twice daily with an optimized background regimen (OBR) in treatment-experienced, HIV-1-infected pediatric patients (3 to <6 years, weighing 10 to <20 kg).

METHODS

The study consisted of an initial 4-week screening period, 48 weeks of treatment and a 4-week follow-up period. Patients initially received darunavir/ritonavir 20/3 mg/kg twice-daily for 2 weeks. Following review of pharmacokinetic, safety and antiviral data, the doses of darunavir/ritonavir were adjusted to 25/3 mg/kg twice-daily for patients <15 kg, and 375/50 mg twice-daily for patients 15 to <20 kg.

RESULTS

Of the 34 patients screened, 21 were treated (median treatment duration 48.6 weeks). Darunavir plus an OBR was well tolerated over 48 weeks, with no new safety concerns, and a comparable safety profile to that seen in older children and adults. All treatment-emergent lipid-related and glucose-related laboratory abnormalities were grade 1 or 2. At week 48, 17 of 21 patients (81.0%) had a confirmed virologic response (intent-to-treat, time-to-loss of virologic response). Improvements in height and weight were seen during the study.

CONCLUSIONS

No new safety concerns were observed over a 48 week period. These results led to lowering the age to 3 years at which darunavir/ritonavir is indicated for use in treatment-experienced pediatric patients. This study also established doses of darunavir to use in treatment-experienced, HIV-1-infected patients aged 3 to <6 years. A high virologic response was observed with this dose. No development of resistance was observed in patients who experienced virologic failure.

Antiretroviral treatment failure, drug resistance, and subtype diversity in the only pediatric HIV clinic in Rhode Island

BACKGROUND

Drug resistance development in the human immunodeficiency virus (HIV)-infected pediatric population in the United States can impact long-term antiretroviral therapy (ART) efficacy. Limited formularies and adherence constraints in children jeopardize lifelong-needed ART.

METHODS

We examined treatment failure, drug resistance, and their correlates in ART-naive and ART-experienced children attending the pediatric HIV clinic in Rhode Island between 1991 and 2012. Pol sequences were obtained for phylogenetic, subtype, and resistance analyses. Associations between selected covariates and virologic failure and resistance were evaluated using generalized additive models and Fisher exact tests.

RESULTS

Data were available for all 56 clinic-attending children. At diagnosis, 33% were aged <1 year, 31% aged 1-4 years, and 37% aged ≥ 5 years; 54% were male, 73% black or Hispanic, 55% US-born, 20% refugees, and 64% perinatally infected. Of 44 ART-experienced children, 57% had virologic failure, most never virologically suppressed. Failure was associated with missed appointments (P = .05) and missed doses (P < .01). Of 40 children with available genotypes, 35% were infected with non-B subtypes; 6% of ART-naive children had resistance; and 73% of ART-experienced children had ≥ 1 major mutation: (16% conferring triple-class, 47% dual-class, and 37% single-class resistance). An epidemiologically confirmed resistance transmission from a perinatally infected teenage male to a newly infected teenage female was demonstrated.

CONCLUSIONS

We report high HIV type 1 diversity, extensive drug resistance among ART-experienced children, and horizontal transmission of resistance in the Rh ode Island pediatric HIV clinic. As HIV-infected children mature into adulthood, close monitoring of ART, adherence, and diagnosis disclosure are essential to optimize patient care.

Systemic antifungal prescribing in neonates and children: outcomes from the Antibiotic Resistance and Prescribing in European Children (ARPEC) Study

The appropriate use of systemic antifungals is vital in the prevention and treatment of invasive fungal infection (IFI) in immunosuppressed children and neonates. This multicenter observational study describes the inpatient prescribing practice of antifungal drugs for children and neonates and identifies factors associated with prescribing variability. A single-day point prevalence study of antimicrobial use in hospitalized neonates and children was performed between October and December 2012. The data were entered through a study-specific Web-based portal using a standardized data entry protocol. Data were recorded from 17,693 patients from 226 centers. A total of 136 centers recorded data from 1,092 children and 380 neonates receiving at least one antifungal agent. The most frequently prescribed systemic antifungals were fluconazole (n=355) and amphotericin B deoxycholate (n=195). The most common indications for antifungal administration in children were medical prophylaxis (n=325), empirical treatment of febrile neutropenia (n=122), and treatment of confirmed or suspected IFI (n=100 [14%]). The treatment of suspected IFI in low-birthweight neonates accounted for the majority of prescriptions in the neonatal units (n=103). An analysis of variance (ANOVA) demonstrated no significant effect of clinical indication (prophylaxis or treatment of systemic or localized infection) on the total daily dose (TDD). Fewer than one-half of the patients (n=371) received a TDD within the dosing range recommended in the current guidelines. Subtherapeutic doses were prescribed in 416 cases (47%). The predominance of fluconazole and high incidence of subtherapeutic doses in participating hospitals may contribute to suboptimal clinical outcomes and an increased predominance of resistant pathogenic fungi. A global consensus on antifungal dosing and coordinated stewardship programs are needed to promote the consistent and appropriate use of antifungal drugs in neonates and children.

Safety and effectiveness of combination antiretroviral therapy during the first year of treatment in HIV-1 infected Rwandan children: a prospective study

Background

With increased availability of paediatric combination antiretroviral therapy (cART) in resource limited settings, cART outcomes and factors associated with outcomes should be assessed.

Methods

HIV-infected children <15 years of age, initiating cART in Kigali, Rwanda, were followed for 18 months. Prospective clinical and laboratory assessments included weight-for-age (WAZ) and height-for-age (HAZ) z-scores, complete blood cell count, liver transaminases, creatinine and lipid profiles, CD4 T-cell count/percent, and plasma HIV-1 RNA concentration. Clinical success was defined as WAZ and WAZ >−2, immunological success as CD4 cells ≥500/mm³ and ≥25% for respectively children over 5 years and under 5 years, and virological success as a plasma HIV-1 RNA concentration <40 copies/mL.

Results

Between March 2008 and December 2009, 123 HIV-infected children were included. The median (interquartile (IQR) age at cART initiation was 7.4 (3.2, 11.5) years; 40% were <5 years and 54% were female. Mean (95% confidence interval (95%CI)) HAZ and WAZ at baseline were −2.01 (−2.23, −1.80) and −1.73 (−1.95, −1.50) respectively and rose to −1.75 (−1.98, −1.51) and −1.17 (−1.38, −0.96) after 12 months of cART. The median (IQR) CD4 T-cell values for children <5 and ≥5 years of age were 20% (13, 28) and 337 (236, 484) cells/mm³respectively, and increased to 36% (28, 41) and 620 (375, 880) cells/mm³. After 12 months of cART, 24% of children had a detectable viral load, including 16% with virological failure (HIV-RNA>1000 c/mL). Older age at cART initiation, poor adherence, and exposure to antiretrovirals around birth were associated with virological failure. A third (33%) of children had side effects (by self-report or clinical assessment), but only 9% experienced a severe side effect requiring a cART regimen change.

Conclusions

cART in Rwandan HIV-infected children was successful but success might be improved further by initiating cART as early as possible, optimizing adherence and optimizing management of side effects.

Long-term virological outcome in children on antiretroviral therapy in the UK and Ireland

Objective:

To assess factors at the start of antiretroviral therapy (ART) associated with long-term virological response in children.

Design:

Multicentre national cohort.

Methods:

Factors associated with viral load below 400 copies/ml by 12 months and virologic failure among children starting 3/4-drug ART in the UK/Irish Collaborative HIV Paediatric Study were assessed using Poisson models.

Results:

Nine hundred and ninety-seven children started ART at a median age of 7.7 years (inter-quartile range 2.9–11.7), 251 (25%) below 3 years: 411 (41%) with efavirenz and two nucleoside reverse transcriptase inhibitors (EFV + 2NRTIs), 264 (26%) with nevirapine and two NRTIs (NVP + 2NRTIs), 119 (12%; 106 NVP, 13 EFV) with non-nucleoside reverse transcriptase inhibitor and three NRTIs (NNRTI + 3NRTIs), and 203 (20%) with boosted protease inhibitor-based regimens. Median follow-up after ART initiation was 5.7 (3.0–8.8) years. Viral load was less than 400 copies/ml by 12 months in 92% [95% confidence interval (CI) 91–94%] of the children. Time to suppression was similar across regimens (P = 0.10), but faster over calendar time, with older age and lower baseline viral load. Three hundred and thirty-nine (34%) children experienced virological failure. Although progression to failure varied by regimen (P < 0.001) and was fastest for NVP + 2NRTIs regimens, risk after 2 years on therapy was similar for EFV + 2NRTIs and NVP + 2NRTIs, and lowest for NNRTI + 3NRTIs regimens (P-interaction = 0.03). Older age, earlier calendar periods and maternal ART exposure were associated with increased failure risk. Early treatment discontinuation for toxicity occurred more frequently for NVP-based regimens, but 5-year cumulative incidence was similar: 6.1% (95% CI 3.9–8.9%) NVP, 8.3% (95% CI 5.6–11.6) EFV, and 9.8% (95% CI 5.7–15.3%) protease inhibitor-based regimens (P = 0.48).

Conclusion:

Viral load suppression by 12 months was high with all regimens. NVP + 3NRTIs regimens were particularly efficacious in the longer term and may be a good alternative to protease inhibitor-based ART in young children.

Determinants of highly active antiretroviral therapy duration in HIV-1-infected children and adolescents in Madrid, Spain, from 1996 to 2012

OBJECTIVES

To investigate the duration of sequential HAART regimens and predictors of first-line regimen discontinuation among HIV-1 vertically infected children and adolescents.

DESIGN

Multicentre survey of antiretroviral-naïve patients enrolled in the HIV-Paediatric Cohor,t CoRISpeS-Madrid Cohort, Spain.

METHODS

Patients with a follow-up of ≥ 1 month spent on HAART, with available baseline CD4 count and HIV-viral load (VL) were included. Time spent on sequential HAART regimens was estimated and multivariable regression was used to identify predictors of time to first-line regimen discontinuation.

RESULTS

104 patients were followed for a median 8 years after starting HAART among 1996-2012; baseline %CD4 was 21.5 (12.3-34.0)and viral load was 5.1 (4.6-5.6) log10 copies/mL. Patients received a mean of 1.9 regimens. Median time on first-line HAART (n = 104) was 64.5 months; second HAART (n = 56) 69.8 months; and third HAART (n = 21) 66.5 months. Eleven (11%) patients were lost to follow-up while on first-line HAART and 54% discontinued (cumulative incidence of 16% and 38% by 1 and 3-year, respectively). The main predictor of first-line regimen discontinuation was suboptimal adherence to antiretrovirals (AHR: 2.60; 95% CI: 1.44-4.70).

CONCLUSIONS

Adherence to therapy was the main determinant of the duration of the first-line HAART regimen in children. It is important to identify patients at high risk for non-adherence, such as very young children and adolescents, in provide special care and support to those patients.

Etravirine in treatment-experienced, HIV-1-infected children and adolescents: 48-week safety, efficacy and resistance analysis of the phase II PIANO study

OBJECTIVES

PIANO (Paediatric study of Intelence As an NNRTI Option; TMC125-C213; NCT00665847) assessed the safety/tolerability, antiviral activity and pharmacokinetics of etravirine plus an optimized background regimen (OBR) in treatment-experienced, HIV-1-infected children (≥ 6 to < 12 years) and adolescents (≥ 12 to < 18 years) over 48 weeks.

METHODS

In a phase II, open-label, single-arm study, 101 treatment-experienced patients (41 children; 60 adolescents) with screening viral load (VL) ≥ 500 HIV-1 RNA copies/mL received etravirine 5.2 mg/kg (maximum dose 200 mg) twice a day (bid) plus OBR.

RESULTS

Sixty-seven per cent of patients had previously used efavirenz or nevirapine. At week 48, the most common treatment-related grade ≥ 2 adverse event (AE) was rash (13%); 12% experienced grade 3 AEs. Only two grade 4 AEs occurred (both thrombocytopaenia, not etravirine related). At week 48, 56% of patients (68% children; 48% adolescents) achieved a virological response (VL<50 copies/mL; intent-to-treat, noncompleter=failure). Factors predictive of response were adherence > 95%, male sex, low baseline etravirine weighted genotypic score and high etravirine trough concentration (C0h ). Seventy-six patients (75%) completed the trial; most discontinuations occurred because of protocol noncompliance or AEs (8% each). Sixty-five per cent of patients were > 95% adherent by questionnaire and 39% by pill count. Forty-one patients experienced virological failure (VF; time-to-loss-of-virological-response non-VF-censored algorithm) (29 nonresponders; 12 rebounders). Of 30 patients with VF with paired baseline/endpoint genotypes, 18 (60%) developed nonnucleoside reverse transcriptase inhibitor (NNRTI) mutations, most commonly Y181C. Mean etravirine area under the plasma concentration-time curve over 12 h (AUC0-12h ; 5216 ng h/mL) and C0h (346 ng/mL) were comparable to adult target values.

CONCLUSIONS

Results with etravirine 5.2 mg/kg bid (with OBR) in this treatment-experienced paediatric population and etravirine 200 mg bid in treatment-experienced adults were comparable. Etravirine is an NNRTI option for treatment-experienced paediatric patients.

Long-term effectiveness of combination antiretroviral therapy and prevalence of HIV drug resistance in HIV-1-infected children and adolescents in Rwanda

OBJECTIVE

To determine the long-term outcomes of treatment and prevalence of genotypic drug resistance in children and adolescents on combination antiretroviral therapy.

METHODS

A cross-sectional study (September 2009 to October 2010) in which clinical, immunologic and virologic outcomes were assessed at a single-study visit and through patient records in a cohort of HIV-infected children and adolescents. Risk factors for clinical and immunologic responses and virologic outcome were evaluated using logistic regression, and the accuracy of clinical and immunologic criteria in identifying virologic failure was assessed.

RESULTS

Four hundred twenty-four patients were enrolled with a median age of 10.8 years (range: 1.7-18.8) and a median duration on combination antiretroviral therapy of 3.4 years (range: 1.0-8.1). Thirty-three percent were stunted and 17% underweight. Eighty-four percent (95% confidence interval: 79-87) of children >5 years had CD4 ≥350 cells/mm and in 74% (95% confidence interval: 62-84) of younger children CD4% was ≥25. CD4 values and age at combination antiretroviral therapy initiation were independently associated with CD4 outcomes; 124 (29%) had HIV-1 RNA ≥1000 copies/mL, with no significant predictors. Sensitivity for weight-for-age and height-for-age and CD4 cells (<350/mm) remained under 50% (15-42%); CD4 cells showed the best specificity, ranging from 91% to 97%. Of 52 samples tested, ≥1 mutations were observed in 91% (nucleoside reverse transcriptase inhibitors) and 95% (non-nucleoside reverse transcriptase inhibitors); 1 to 2 thymidine analogue-associated mutations were detected in 16 (31%) and ≥3 thymidine analogue-associated mutations in 7 (13%).

CONCLUSION

Nearly 1 in 3 children showed virologic failure, and >10% of the subgroup of children with treatment failure in whom genotyping was performed demonstrated multiple HIV drug resistance mutations. Neither clinical condition nor CD4 cells were good indicators for treatment failure.

Understanding dosing: children are small adults, neonates are immature children

Paediatric dose cannot be scaled down directly from an adult using weight (eg, mg/kg). This results in a dose too small in infants and children because elimination does not change in direct proportion to weight, and a dose too large in neonates whose drug elimination pathways are immature. The goal of treatment is a desired response (the target effect). An understanding of the concentration-response relationship (pharmacodynamics) can be used to predict the target concentration required to achieve this target effect. Pharmacokinetic knowledge then determines the target dose that will achieve the target concentration. Variability associated with both pharmacokinetics and pharmacodynamics can be reduced by demographic information (covariates), which can be used to help predict the target dose in a specific child. The covariates of size, maturation and organ function are the three principle contributors to pharmacokinetic variability. Children (2 years postnatal age or older) are essentially similar to adults (ie, mature) and differ only in size. Maturation processes are only important in neonates and infants, therefore, this cohort can be viewed as immature children. Paediatric pharmacodynamic studies are fewer than pharmacokinetic studies, but are required to elucidate the target concentration and consequent dose. The lack of pharmacodynamic studies is a serious challenge for rational dosing.

Effect of HIV genotypic drug resistance testing on the management and clinical course of HIV-infected children and adolescents

The clinical utility of genotypic drug resistance testing (DRT) in HIV-infected children on antiretroviral therapy (ART) is not well understood. HIV-infected patients aged <19 years undergoing DRT for virological failure were retrospectively enrolled. Indications for DRT and changes in HIV RNA load were recorded. Between January 2000 and December 2006, 57 patients had DRT. The most common indication for DRT was poor ART adherence (57.7% of patients). ART was changed in 50.9% of patients after DRT. Poor adherence was cited by clinicians for not changing ART significantly more often than any other reason (47.3%, P < 0.001). After DRT, significant improvement in HIV RNA load occurred independent of ART changes, though patients whose ART was modified were more likely to become undetectable (31.5% versus 7.0%, P < 0.001). Poor adherence was a significant factor for ordering DRT and for not changing ART in HIV-infected children.

Off-label medicine use in children and adolescents: results of a population-based study in Germany

Background

Population-based self-reported data on off-label medicine use independent from health care provisions are lacking. The purpose of this study is to investigate off-label medicine use in children and adolescents in Germany in a non-clinical setting and to identify prevalence, determinants and spectrum of off-label medicine use.

Methods

Data were obtained from the German Health Interview and Examination Survey for Children and Adolescents (KiGGS) conducted by the Robert Koch Institute (2003–2006). 17,450 randomly selected children aged 0–17 years took part in the drug interviews. Of those, 8,899 took at least one medicine during the 7 days preceding the interview. Off-label medicine use was defined as the discrepancy between actual use and the intended use described in the summary of product characteristics. Off-label medicine use was stratified into off-label indication, off-label age, off-label over-dosing, and off-label under-dosing.

Results

The prevalence rate of off-label medicine use among those who used medicines amount of is 40.2%. The prevalence rate is significantly higher in boys (41.4%), in children aged 3 to 6 years (48.7%), without migration background (40.9%), with high social status (42.5%), living in small (42.0%) and medium sized cities (41.6%), and with a poor parents rated health status (41.7%). 12,667 preparations (attributable in respect to off-label use) were taken by 8,899 children. 30% of the medicines have been used off-label. Off-label medicine use was highest in preparations of the ATC-class “C00 Cardiovascular System”. In all origins of medicine, all age groups and all ATC-classes under-dosing was the most frequent reason for off-label medicine use.

Conclusions

There is a considerable level of self-reported off-label medicines use in the general paediatric population. Further investigations are needed to examine in how far off-label medicine use is based on lack of knowledge or on empiricism in paediatric pharmacotherapy. Attention also needs to be paid to under-dosing which potentially exposes drug users to risks of side effects without the benefit of a therapeutic effect. Clinical trials for licensing of paediatric medicines, education of health care professionals, but also of parents and carers are needed to ensure the rational use of medicines.

Short communication: high rates of thymidine analogue mutations and dual-class resistance among HIV-infected Ugandan children failing first-line antiretroviral therapy

HIV-infected children are at high risk of acquiring drug-resistant viruses, which is of particular concern in settings where antiretroviral drug options are limited. We aimed to assess resistance patterns and predict viral drug susceptibility among children with first-line antiretroviral therapy (ART) failure in Uganda. A cross-sectional analysis of children switching ART regimens due to first-line failure was performed at three clinical sites in Uganda. HIV-RNA determination and genotypic resistance testing on all specimens with HIV-RNA >1,000 copies/ml were performed. Major drug resistance mutations were scored using the 2011 International Antiviral Society-USA list. The Stanford algorithm was used to predict drug susceptibility. At the time of switch, 44 genotypic resistance tests were available for 50 children. All children harbored virus with nonnucleoside reverse transcriptase inhibitor (NNRTI) resistance [95% confidence interval (CI) 92-100%] and NRTI resistance was present in 98% (95% CI 88-100%). Forty-six percent (95% CI 30-61%) of children harbored ≥2 thymidine analog mutations. M184V was identified as the only NRTI mutation in 27% (95% CI 15-43%). HIV susceptibility to NRTIs, with the exception of tenofovir, was reduced in ≥60% of children. Ugandan children experiencing first-line ART failure in our study harbored high rates of dual-class and accumulated HIV drug resistance. Methods to prevent treatment failure, including adequate pediatric formulations and alternative second-line treatment options, are urgently needed.

Lopinavir dosing in HIV-infected children in the United Kingdom and Ireland

BACKGROUND

Uncertainty surrounds the correct dosing of lopinavir/r (LPV/r) in HIV-infected children not receiving non-nucleoside reverse transcriptase inhibitors. The licensed total daily dose is 460 mg/m², whereas the original study, reporting excellent viral load (VL) suppression, used a higher 600 mg/m² dose.

METHODS

We calculated LPV/r daily doses prescribed from 2000 to 2009 within the UK/Irish national Collaborative HIV Paediatric Study (CHIPS) cohort. Logistic and binomial mixed models were used to explore whether higher LPV/r doses affected VL suppression.

RESULTS

Four hundred forty-four of 1201 (37%) children on antiretroviral therapy in CHIPS had taken lopinavir/r without non-nucleoside reverse transcriptase inhibitors. Of 1065 recorded doses, 48% were syrup, 27% capsules and 25% tablets. Ten percent of doses were >10% below 460 mg/m² per day, and 12% were >10% above 600 mg/m². In multivariable models, predictors of lower doses were: once versus twice daily dosing (32 mg/m² lower); syrup versus tablets/capsules (33 mg/m² lower); higher weight-for-age and height-for-age (24 mg/m² and 13 mg/m² lower per unit higher, respectively); and older age (13 mg/m lower per year older for those aged >10 years, P < 0.05). Dosing varied widely by hospital (P = 0.0004), with some targeting higher and others lower doses. For those receiving lopinavir/r for ≥6 months, there was a greater chance of VL <400 copies/mL with higher doses (odds ratio = 1.15 [95% confidence interval: 1.06-1.25 per 50 mg/m² higher], P = 0.001).

CONCLUSIONS

Findings suggest substantial variation and large hospital-level effects in the LPV/r dose prescribed to HIV-infected children in the United Kingdom/Ireland. Higher doses appeared to improve long-term VL suppression, which may be critical in children who need life-long therapy. Results highlight the importance of optimizing dosing in HIV-infected children of all ages.

Adherence to antiretroviral therapy and acceptability of planned treatment interruptions in HIV-infected children

There have been no paediatric randomised trials describing the effect of planned treatment interruptions (PTIs) of antiretroviral therapy (ART) on adherence, or evaluating acceptability of such a strategy. In PENTA 11, HIV-infected children were randomised to CD4-guided PTIs (n = 53) or continuous therapy (CT, n = 56). Carers, and children if appropriate, completed questionnaires on adherence to ART and acceptability of PTIs. There was no difference in reported adherence on ART between CT and PTI groups; non-adherence (reporting missed doses over the last 3 days or marking <100 % adherence since the last clinical visit on a visual analogue scale) was 18 % (20/111) and 14 % (12/83) on carer questionnaires in the CT and PTI groups respectively (odds ratios, OR (95 % CI) = 1.04 (0.20, 5.41), χ² (1) = 0.003, p = 0.96). Carers in Europe/USA reported non-adherence more often (31/121, 26 %) than in Thailand (1/73, 1 %; OR (95 % CI) = 54.65 (3.68, 810.55), χ² (1) = 8.45, p = 0.004). The majority of families indicated they were happy to have further PTIs (carer: 23/36, 64 %; children: 8/13, 62 %), however many reported more clinic visits during PTI were a problem (carer: 15/36, 42 %; children: 6/12, 50 %).

The needs for HIV treatment and care of children, adolescents, pregnant women and older people in low-income and middle-income countries

OBJECTIVE

Success in diagnosing and treating HIV-infected adults has, where HIV care and treatment is available, turned HIV into a chronic, rather than life-limiting disease. Progress meeting the needs of HIV-infected children, perinatally and horizontally infected adolescents, pregnant women and older people has lagged behind. We review the special needs and barriers to scaling up care and antiretroviral therapy (ART) coverage in these populations.

DESIGN AND METHODS

A literature review combined with personal views and operational experience specifically from countries covered by the Evidence for Action programme.

RESULTS

Challenges include logistics of diagnosis and treatment in pregnancy, difficulties in early infant diagnosis, availability of appropriate paediatric formulations, management of adolescents, and comorbidities in older people.

CONCLUSION

Priorities for development need to focus upon the simplification of HIV care to allow provision for all ages at the primary healthcare level. Specific priorities include focused use of virological testing in infants, ongoing development of dispersible and scored fixed-dose ART combinations suitable for use across ages, development of 'adolescent-friendly' HIV services catering for perinatally and horizontally infected adolescents to improve adherence and reduce onward transmissions, simplification of referral pathways to ensure all pregnant women are tested for HIV and commenced on ART, and education of healthcare workers on the specific needs of HIV care in older patients. Each priority will be reviewed and potential solutions discussed.

The unanswered question: when to initiate antiretroviral therapy in children with HIV infection

PURPOSE OF REVIEW

The question of when to initiate antiretroviral treatment for children is perhaps the most critical unanswered question in pediatric HIV therapeutics. With large numbers of children throughout the world acquiring HIV infection and with improved global access to HIV treatment it is particularly timely to consider the optimal time to initiate antiretroviral therapy in infants, children and adolescents.

RECENT FINDINGS

Early treatment can result in suppression of HIV viremia, immune preservation and prevention of disease progression. This must be balanced by the challenges of maintaining adherence to multidrug regimens, the risks of selecting drug-resistant virus, and long and short-term toxicities of medications.

SUMMARY

This review provides a framework within which to consider when to initiate children on antiretroviral treatment. A child's age and developmental status, where they live, and the goals and expectations for treatment provide a context for balancing the risks of disease progression with the risks of drug-related toxicities and viral resistance.

How can we simplify antiretroviral therapy in children?

PURPOSE OF REVIEW

The aim of this article is to present approaches towards simplifying pediatric antiretroviral therapy in order to improve access to care, coverage of HIV-positive children, and support adherence to treatment.

RECENT FINDINGS

Barriers to rapid and effective global scale-up of pediatric antiretroviral therapy include the narrow range of available pediatric antiretrovirals, complicated dosing schedules, and social and economic instability of the family caused by poverty, stigma, and death. Healthcare providers can simplify antiretroviral therapy delivery by promoting the development and use of pediatric fixed dose combinations and scored adult antiretrovirals, using weight-band dosing tables to prescribe antiretrovirals, and identifying less complex regimens. Caretakers would benefit from active counseling to facilitate more open communication with their children about adherence and disclosure. Children can develop long-term coping strategies through learning life skills that build confidence and improve decision-making. Whenever possible, antiretroviral therapy programs should provide access to free antiretrovirals, identify funds to cover transportation costs, and refer families to available community support programs.

SUMMARY

Interventions to simplify the administration of antiretroviral therapy need to address not only how antiretrovirals are prescribed and formulated, but the relationships of HIV-positive children with their families and communities as well.

Age-related expansion of Tim-3 expressing T cells in vertically HIV-1 infected children

As perinatally HIV-1-infected children grow into adolescents and young adults, they are increasingly burdened with the long-term consequences of chronic HIV-1 infection, with long-term morbidity due to inadequate immunity. In progressive HIV-1 infection in horizontally infected adults, inflammation, T cell activation, and perturbed T cell differentiation lead to an "immune exhaustion", with decline in T cell effector functions. T effector cells develop an increased expression of CD57 and loss of CD28, with an increase in co-inhibitory receptors such as PD-1 and Tim-3. Very little is known about HIV-1 induced T cell dysfunction in vertical infection. In two perinatally antiretroviral drug treated HIV-1-infected groups with median ages of 11.2 yr and 18.5 yr, matched for viral load, we found no difference in the proportion of senescent CD28(-)CD57(+)CD8(+) T cells between the groups. However, the frequency of Tim-3(+)CD8(+) and Tim-3(+)CD4(+) exhausted T cells, but not PD-1(+) T cells, was significantly increased in the adolescents with longer duration of infection compared to the children with shorter duration of HIV-1 infection. PD-1(+)CD8(+) T cells were directly associated with T cell immune activation in children. The frequency of Tim-3(+)CD8(+) T cells positively correlated with HIV-1 plasma viral load in the adolescents but not in the children. These data suggest that Tim-3 upregulation was driven by both HIV-1 viral replication and increased age, whereas PD-1 expression is associated with immune activation. These findings also suggest that the Tim-3 immune exhaustion phenotype rather than PD-1 or senescent cells plays an important role in age-related T cell dysfunction in perinatal HIV-1 infection. Targeting Tim-3 may serve as a novel therapeutic approach to improve immune control of virus replication and mitigate age related T cell exhaustion.

Pharmacokinetics and short-term safety and tolerability of etravirine in treatment-experienced HIV-1-infected children and adolescents

OBJECTIVES

To evaluate the pharmacokinetics, weight-based dose selection and short-term safety and tolerability of etravirine in HIV-1-infected children and adolescents.

DESIGN

Phase I, nonrandomized, open-label study in two stages.

METHODS

Children and adolescents aged at least 6 years to 17 years or less on a stable lopinavir/ritonavir-based antiretroviral regimen with HIV-1 RNA plasma viral load less than 50 copies/ml were enrolled. In both stages, etravirine (4 mg/kg twice daily in stage I, 5.2 mg/kg twice daily in stage II), added to the existing antiretroviral regimen, was administered for 7 days followed by a morning dose and 12-h pharmacokinetic assessment on day 8. Pharmacokinetic parameters were determined using noncompartmental analysis. Data were compared with those previously established in HIV-1-infected adults on a similar etravirine (200 mg twice daily) combination antiretroviral regimen.

RESULTS

Twenty-one patients were recruited to each stage; 19 and 20 had evaluable pharmacokinetics in stages I and II, respectively. Mean (SD) maximum plasma concentrations in stages I and II were 495 (453) and 757 ng/ml (680), respectively; area under the plasma concentration-time curve over 12 h was 4050 (3602) and 6141 ng h/ml (5586), respectively. Statistical/qualitative comparisons showed comparable exposures with adults in stage II; however, the upper 90% confidence interval fell outside the predefined range. Plasma viral load remained undetectable on day 8 in all patients, and etravirine was well tolerated at both doses.

CONCLUSION

Etravirine 5.2 mg/kg was well tolerated in this study and this dose was selected for further investigation in clinical trials.

HIV-1-resistance-associated mutations after failure of first-line antiretroviral treatment among children in resource-poor regions: a systematic review

HIV-positive children are at high risk of drug resistance, which is of particular concern in settings where antiretroviral options are limited. In this Review we explore resistance rates and patterns among children in developing countries in whom antiretroviral treatment has failed. We did a systematic search of online databases and conference abstracts and included studies reporting HIV-1 drug resistance after failure of first-line paediatric regimens in children (<18 years) in resource-poor regions (Latin America, Africa, and Asia). We retrieved 1312 citations, of which 30 studies reporting outcomes in 3241 children were eligible. Viruses with resistance-associated mutations were isolated from 90% (95% CI 88-93%) of children. The prevalence of mutations associated with nucleoside reverse transcriptase inhibitors was 80%, with non-nucleoside reverse transcriptase inhibitors was 88%, and with protease inhibitors was 54%. Methods to prevent treatment failure, including adequate paediatric formulations and affordable salvage treatment options are urgently needed.