Optimising Paediatric HIV Treatment: Recent Developments and Future Directions.

Treatment options for children living with HIV have historically been less effective, less practical and more difficult to implement compared with those for adults, as the research and development of new drugs for children has lagged behind. Significant progress has been achieved in response to the paediatric HIV epidemic over the last decade. Several optimised paediatric antiretroviral formulations are currently available or in development, including fixed-dose combination tablets containing a complete World Health Organization-recommended regimen.

Simultaneous pharmacokinetic modeling of unbound and total darunavir with ritonavir in adolescents: a substudy of the SMILE trial.

Darunavir (DRV) is an HIV protease inhibitor commonly used as part of antiretroviral treatment regimens globally for children and adolescents. It requires a pharmacological booster, such as ritonavir (RTV) or cobicistat. To better understand the pharmacokinetics (PK) of DRV in this younger population and the importance of the RTV boosting effect, a population PK substudy was conducted within SMILE trial, where the maintenance of HIV suppression with once daily integrate inhibitor + darunavir/ritonavir in children and adolescents is evaluated.

Dolutegravir as First- or Second-Line Treatment for HIV-1 Infection in Children.

Background: Children with human immunodeficiency virus type 1 (HIV-1) infection have limited options for effective antiretroviral treatment (ART).

Methods: We conducted an open-label, randomized, noninferiority trial comparing three-drug ART based on the HIV integrase inhibitor dolutegravir with standard care (non-dolutegravir-based ART) in children and adolescents starting first- or second-line ART. The primary end point was the proportion of participants with virologic or clinical treatment failure by 96 weeks, as estimated by the Kaplan-Meier method.

ODYSSEY clinical trial design: a randomised global study to evaluate the efficacy and safety of dolutegravir-based antiretroviral therapy in HIV-positive children, with nested pharmacokinetic sub-studies to evaluate pragmatic WHO-weight-band based dolutegravir dosing.

Background: Dolutegravir (DTG)-based antiretroviral therapy (ART) is highly effective and well-tolerated in adults and is rapidly being adopted globally. We describe the design of the ODYSSEY trial which evaluates the efficacy and safety of DTG-based ART compared with standard-of-care in children and adolescents. The ODYSSEY trial includes nested pharmacokinetic (PK) sub-studies which evaluated pragmatic World Health Organization (WHO) weight-band-based DTG dosing and opened recruitment to children < 14 kg while dosing was in development.

Weekends-off efavirenz-based antiretroviral therapy in HIV-infected children, adolescents and young adults (BREATHER): Extended follow-up results of a randomised, open-label, non-inferiority trial.

Background: Weekends off antiretroviral therapy (ART) may help engage HIV-1-infected young people facing lifelong treatment. BREATHER showed short cycle therapy (SCT; 5 days on, 2 days off ART) was non-inferior to continuous therapy (CT) over 48 weeks. Planned follow-up was extended to 144 weeks, maintaining original randomisation.

Hepatic, Renal, Hematologic, and Inflammatory Markers in HIV-Infected Children on Long-term Suppressive Antiretroviral Therapy.

Background: Data on long-term toxicity of antiretroviral therapy (ART) in HIV-infected children are sparse. PENPACT-1 was an open-label trial in which HIV-infected children were assigned randomly to receive protease inhibitor (PI)- or nonnucleoside reverse-transcriptase inhibitor (NNRTI)-based ART.

Methods: We examined changes in clinical, immunologic, and inflammatory markers from baseline to year 4 in the subset of children in the PENPACT-1 study who experienced viral suppression between week 24 and year 4 of ART.

Neurocognition and quality of life after reinitiating antiretroviral therapy in children randomized to planned treatment interruption.

Objective: Understanding the effects of antiretroviral treatment (ART) interruption on neurocognition and quality of life (QoL) are important for managing unplanned interruptions and planned interruptions in HIV cure research.

Design: Children previously randomized to continuous (continuous ART, n = 41) vs. planned treatment interruption (PTI, n = 47) in the Pediatric European Network for Treatment of AIDS (PENTA) 11 study were enrolled.

HIV-1 Drug Resistance and Second-Line Treatment in Children Randomized to Switch at Low Versus Higher RNA Thresholds.

Background: The PENPACT-1 trial compared virologic thresholds to determine when to switch to second-line antiretroviral therapy (ART). Using PENPACT-1 data, we aimed to describe HIV-1 drug resistance accumulation on first-line ART by virologic threshold.

Methods: PENPACT-1 had a 2 × 2 factorial design, randomizing HIV-infected children to start protease inhibitor (PI) versus nonnucleoside reverse transcriptase inhibitor (NNRTI)-based ART, and switch at a 1000 copies/mL versus 30,000 copies/mL threshold.

Early antiretroviral therapy in children perinatally infected with HIV: a unique opportunity to implement immunotherapeutic approaches to prolong viral remission.

From the use of antiretroviral therapy to prevent mother-to-child transmission to the possibility of HIV cure hinted at by the Mississippi baby experience, paediatric HIV infection has been pivotal to our understanding of HIV pathogenesis and management. Daily medication and indefinite antiretroviral therapy is recommended for children infected with HIV. Maintenance of life-long adherence is difficult and the incidence of triple-class virological failure after initiation of antiretroviral therapy increases with time.

Pharmacokinetics of pediatric lopinavir/ritonavir tablets in children when administered twice daily according to FDA weight bands.

Background: Lopinavir/ritonavir (LPV/r) pediatric tablets (100/25 mg) are approved by the United States Food and Drug Administration (FDA) and European Medicines Agency (EMA) as part of combination antiretroviral therapy. Dosing is based on body weight bands or body surface area under FDA approval and only body surface area by the EMA. This can lead to a different recommended dose.

Outcomes after reinitiating antiretroviral therapy in children randomized to planned treatment interruptions.

Background: Excess risks for death/opportunistic disease in adults randomized to CD4-driven planned treatment interruption (PTI) in the Strategies for Management of Antiretroviral Therapy (SMART) trial remained after antiretroviral therapy (ART) re-initiation. Risks for children following PTI were evaluated in long-term follow-up of children in the PENTA 11 trial.

Methods: Children with HIV RNA below 50 copies/ml and CD4 at least 30% (2-6 years) or at least 500 cells/μl (7-15 years) were randomized to continuous ART (cART) or PTI in PENTA 11 (ISRCTN 36694210).

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.

First-line antiretroviral therapy with a protease inhibitor versus non-nucleoside reverse transcriptase inhibitor and switch at higher versus low viral load in HIV-infected children: an open-label, randomised phase 2/3 trial.

Background: Children with HIV will be on antiretroviral therapy (ART) longer than adults, and therefore the durability of first-line ART and timing of switch to second-line are key questions. We assess the long-term outcome of protease inhibitor and non-nucleoside reverse transcriptase inhibitor (NNRTI) first-line ART and viral load switch criteria in children.

Methods: In a randomised open-label factorial trial, we compared effectiveness of two nucleoside reverse transcriptase inhibitors (NRTIs) plus a protease inhibitor versus two NRTIs plus an NNRTI and of switch to second-line ART at a viral load of 1000 copies per mL versus 30,000 copies per mL in previously untreated children infected with HIV from Europe and North and South America.

PENTA 2009 guidelines for the use of antiretroviral therapy in paediatric HIV-1 infection.

PENTA Guidelines aim to provide practical recommendations for treating children with HIV infection in Europe. Changes to guidance since 2004 have been informed by new evidence and by expectations of better outcomes following the ongoing success of antiretroviral therapy (ART). Participation in PENTA trials of simplifying treatment is encouraged.

Pregnancy outcomes in women with HIV type-1 receiving a lopinavir/ritonavir-containing regimen.

Background: The pregnancy-related adverse effects of antiretroviral therapy (ART) have yielded discordant results, which could be explained in part by the heterogeneity of ART protocols. The objective of our study was to explore whether lopinavir/ritonavir (LPV/r) exposure during pregnancy is associated with adverse outcomes.

Methods: Data on 100 consecutive HIV type-1 (HIV-1)-infected women receiving LPV/r during pregnancy and who delivered after 15 weeks gestational age (GA) between January 2003 and June 2007 in a single centre were analysed.

Population analysis of the pregnancy-related modifications in lopinavir pharmacokinetics and their possible consequences for dose adjustment.

Objectives: To investigate the possible necessity of an increase in lopinavir dose during pregnancy in order to achieve the concentrations previously defined as predictive of virological efficacy.

Patients And Methods: Lopinavir pharmacokinetics were investigated by a population approach performed on 145 HIV-infected women, including 74 pregnant women. The final model was used to determine the probability of achievement of the target trough concentrations by Monte Carlo simulations.

Plasma drug concentrations and virologic evaluations after stopping treatment with nonnucleoside reverse-transcriptase inhibitors in HIV type 1-infected children.

Background: The optimum strategy for stopping treatment with drugs that have different half-lives in a combination regimen to minimize the risk of selecting drug-resistant viruses remains unknown. We evaluated drug concentrations in plasma, human immunodeficiency virus (HIV) load, and development of drug resistance after a planned treatment interruption of a nonnucleoside reverse-transcriptase inhibitor (NNRTI)-containing regimen in HIV type 1-infected children.

Methods: Children with viral loads <50 copies/mL and CD4 cell percentages > or =30% (for children aged 2-6 years) or CD4 cell percentages > or =25% and CD4 cell counts > or =500 cells/microL (for children aged 7-15 years) were randomized to either a planned treatment interruption or to continuous therapy.

A randomized controlled trial of genotypic HIV drug resistance testing in HIV-1-infected children: the PERA (PENTA 8) trial.

Objective: To evaluate the longer-term utility of genotypic resistance testing in HIV-1-infected children with virological failure.

Methods: Children aged 3 months-18 years switching antiretroviral therapy (ART) with HIV-1 RNA > 2,000 copies/ml were randomized between genotypic testing (Virtual Phenotype) and no testing at baseline and subsequent virological failures. Children were followed to at least 96 weeks.

Bayesian parameter estimates of nelfinavir and its active metabolite, hydroxy-tert-butylamide, in infants perinatally infected with human immunodeficiency virus type 1.

The objective of the present study was to develop a population pharmacokinetic model for nelfinavir mesylate (NFV) and nelfinavir hydroxy-tert-butylamide (M8), the most abundant metabolite of NFV, in infants vertically infected with human immunodeficiency virus type 1 and participating in the Paediatric European Network for Treatment of AIDS 7 study. Plasma NFV concentrations were determined during repeated NFV administrations (two to three times a day). Eighteen infants younger that age 2 years participated in this study.

Persistence of multidrug-resistant HIV-1 without antiretroviral treatment 2 years after sexual transmission.

Objectives: To understand the virological mechanisms of 2-year persistence of multidrug-resistant virus without selective antiretroviral pressure in HIV-1-infected patients.

Patients And Methods: Two patients were contaminated recently by their HIV-1-infected partners, who had received, before the transmission, all available antiretroviral drugs and who exhibited a severe therapeutic failure. The resistance mutations analysis was performed by clonal sequencing of 1.

Evolution of antiretroviral phenotypic and genotypic drug resistance in antiretroviral-naive HIV-1-infected children treated with abacavir/lamivudine, zidovudine/lamivudine or abacavir/zidovudine, with or without nelfinavir (the PENTA 5 trial).

Purpose And Methods: To describe the evolution of resistance to zidovudine (ZDV), lamivudine (3TC), abacavir (ABC) and nelfinavir (NFV), 113 previously untreated children in the PENTA 5 trial had resistance assayed at baseline, rebound and/or 24, 48, 72 weeks (VIRCO: phenotyping and genotyping with 'Virtual Phenotype' interpretation).

Results: At baseline, few reverse transcriptase mutations and no primary protease inhibitor mutations were observed. Time to detectable HIV-1 RNA with reduced phenotypic susceptibility to any drug was shortest in the ZDV+3TC arm (overall logrank P=0.

Pharmacokinetics of nelfinavir and its active metabolite, hydroxy-tert-butylamide, in infants perinatally infected with human immunodeficiency virus type 1.

Background: In children younger than 2 years of age vertically infected with HIV-1, the recommended pediatric dosing regimen for nelfinavir (20 to 30 mg/kg three times a day) provides insufficient drug exposure. This study was conducted to determine the steady state pharmacokinetics of nelfinavir and its active metabolite, M8, in this population.

Methods: Fourteen infants (2.