Population Pharmacokinetic Modeling of Dolutegravir to Optimize Pediatric Dosing in HIV-1-Infected Infants, Children, and Adolescents.

BACKGROUND AND OBJECTIVE: HIV treatment options remain limited in children. Dolutegravir is a potent and well-tolerated, once-daily HIV-1 integrase inhibitor recommended for HIV-1 infection in both adults and children down to 4 weeks of age. To support pediatric dosing of dolutegravir in children, we used a population pharmacokinetic model with dolutegravir data from the P1093 and ODYSSEY clinical trials. The relationship between dolutegravir exposure and selected safety endpoints was also evaluated. METHODS: A population pharmacokinetic model was developed with data from P1093 and ODYSSEY to characterize the pharmacokinetics and associated variability and to evaluate the impact of pharmacokinetic covariates. The final population pharmacokinetic model simulated exposures across weight bands, doses, and formulations that were compared with established adult reference data. Exploratory exposure-safety analyses evaluated the relationship between dolutegravir pharmacokinetic parameters and selected clinical laboratory parameters and adverse events. RESULTS: A total of N = 239 participants were included, baseline age ranged from 0.1 to 17.5 years, weight ranged from 3.9 to 91 kg, 50% were male, and 80% were black. The final population pharmacokinetic model was a one-compartment model with first-order absorption and elimination, enabling predictions of dolutegravir concentrations in the pediatric population across weight bands and doses/formulations. The predicted geometric mean trough concentration was comparable to the adult value following a 50-mg daily dose of dolutegravir for all weight bands at recommended doses. Body weight, age, and formulation were significant predictors of dolutegravir pharmacokinetics in pediatrics. Additionally, during an exploratory exposure-safety analysis, no correlation was found between dolutegravir exposure and selected safety endpoints or adverse events. CONCLUSIONS: The dolutegravir dosing in children ≥ 4 weeks of age on an age/weight-band basis provides comparable exposures to those historically observed in adults. Observed pharmacokinetic variability was higher in this pediatric population and no additional safety concerns were observed. These results support the weight-banded dosing of dolutegravir in pediatric participants currently recommended by the World Health Organization.

Cancer risk among HIV-exposed uninfected children in the United States.

In utero exposure to didanosine was associated with increased risk of brain cancer in a French study. We used United States health department records to assess cancer risk among 13 617 children exposed to HIV in utero , who remained HIV-uninfected after birth (1990-2017). Risk of brain tumors was borderline elevated among these children (standardized incidence ratio 2.2, 95% confidence interval 0.8-4.8, P  = 0.12, based on six cases). Risk was not significantly increased for leukemia or other cancers.

Analyzing Longitudinally Collected Viral Load Measurements in Youth With Perinatally Acquired HIV Infection: Problems and Possible Remedies.

Human immunodeficiency virus (HIV) viral load (VL) is an important quantitative marker of disease progression and treatment response in people living with HIV infection, including children with perinatally acquired HIV. Measures of VL are often used to predict different outcomes of interest in this population, such as HIV-associated neurocognitive disorder. One popular approach to summarizing historical viral burden is the area under a time-VL curve (AUC). However, alternative historical VL summaries (HVS) may better answer the research question of interest. In this article, we discuss and contrast the AUC with alternative HVS, including the time-averaged AUC, duration of viremia, percentage of time with suppressed VL, peak VL, and age at peak VL. Using data on youth with perinatally acquired HIV infection from the Pediatric HIV/AIDS Cohort Study Adolescent Master Protocol, we show that HVS and their associations with full-scale intelligence quotient depend on when the VLs were measured. When VL measurements are incomplete, as can be the case in observational studies, analysis results may be subject to selection bias. To alleviate bias, we detail an imputation strategy, and we present a simulation study demonstrating that unbiased estimation of a historical VL summary is possible with a correctly specified imputation model.

Pharmacokinetics, safety, tolerability, and antiviral activity of dolutegravir dispersible tablets in infants and children with HIV-1 (IMPAACT P1093): results of an open-label, phase 1-2 trial.

BACKGROUND: Safe and potent antiretroviral medications in child-friendly formulations are needed to treat young children living with HIV-1. We aimed to select dosing for a dispersible tablet formulation of dolutegravir that achieved pharmacokinetic exposures similar to those in adults, and was safe and well tolerated in young children. METHODS: International Maternal Pediatric Adolescent AIDS Clinical Trial (IMPAACT) P1093 is a phase 1-2 ongoing multicentre, open-label, non-comparative study of dolutegravir. A 5 mg dispersible tablet formulation of dolutegravir was studied in children aged 4 weeks to less than 6 years old, weighing at least 3 kg, with HIV RNA of greater than 1000 copies per mL and no previous treatment with integrase strand transfer inhibitor recruited from IMPAACT clinical research sites in Africa, the Americas, and Asia. Doses were selected on the basis of intensive pharmacokinetic evaluation on days 5-10, with safety and tolerability assessed up to 48 weeks. The primary objectives of this study are to evaluate the pharmacokinetics of dolutegravir in combination with optimised background therapy and to establish the dose of dolutegravir that achieves the targeted 24-h trough concentration and 24-h area under the curve for infants, children, and adolescents with HIV-1, to establish the safety and tolerability of dolutegravir at 24 and 48 weeks, and to select a dose that achieves similar exposure to the dolutegravir 50 mg once daily dose in adults. This analysis included participants treated with the proposed dose of dolutegravir dispersible tablets in two stages for each of three age cohorts. This trial is registered at ClinicalTrials.gov (NCT01302847) and is ongoing. FINDINGS: We recruited 181 participants from April 20, 2011, to Feb 19, 2020; of these, 96 received dolutegravir dispersible tablets. This analysis included 73 (35, 48% female) participants who received the final proposed dose with median (range) age of 1 year (0·1 to 6·0), weight (minimum-maximum) of 8·5 kg (3·7 to 18·5), plasma HIV-1 RNA concentration of 4·2 log10 copies per mL (2·1 to 7·0), and CD4% of 24·0% (0·3 to 49·0); 64 (87·7%) were treatment-experienced. The selected dose within each age cohort (≥2 years to <6 years, ≥6 months to <2 years of age and ≥4 weeks to <6 months) achieved geometric mean trough (ng/mL) of 688, 1179, and 1446, and 24 h area-under-the-curve (h·mg/L) of 53, 74, and 65, respectively. No grade 3 or worse adverse events were attributed to dolutegravir. INTERPRETATION: In this study, the proposed once daily dosing of dolutegravir dispersible tablets provided drug exposures similar to those for adults, and was safe and well tolerated. These data support the use of dolutegravir dispersible tablets as first-line or second-line treatment for infants and children aged less than 6 years living with HIV-1. FUNDING: National Institute of Allergy and Infectious Diseases, the Eunice Kennedy Shriver National Institute of Child Health and Human Development, the National Institute of Mental Health, and ViiV Healthcare-GlaxoSmithKline.

World Prematurity Day: it takes an NIH village to prevent preterm birth and improve treatments for preterm infants.

Prematurity remains a major cause of morbidity and mortality. Research to prevent preterm birth and improve treatments for preterm infants involves both intramural and extramural research, not just at the National Institute of Child Health and Human Development, but across many institutes and centers at the National Institutes of Health.

Outcomes of retained and disengaged pregnant women living with HIV in Uganda.

INTRODUCTION: Loss-to-follow-up among women living with HIV (WLWHIV) may lead to unfavorable outcomes for both mother and exposed infant. This study traced WLWHIV disengaged from care and their infants and compared their outcomes with those retained in care. METHODS: The study included WLWHIV who initiated ART during pregnancy at six public clinics in Uganda. A woman was defined as disengaged (DW) if she had not attended her 6-week post-partum visit by 10 weeks after her estimated date of delivery. DW were matched with retained women (RW) by age and duration on ART. Nurse counselors traced all selected DW via telephone and community visits to assess vital status, infant HIV sero-status and maternal HIV viral load through blood draws. RESULTS: Between July 2017 and July 2018, 734 women (359 DW and 375 RW) were identified for the study. Tracing was attempted on 349 DW and 160 (44.6%) were successfully located and enrolled in the study. They were matched with 162 RW. Among DW, 52 (32.5%) transferred to another health facility. Very few DW, 39.0% were HIV virally suppressed (<1000 copies/ml) compared to RW 89.5%, P<0.001). Among 138 babies born to DW, 4.3% tested positive for HIV compared to 1.4% among babies born to RW (P = 0.163). CONCLUSION: Pregnant and breastfeeding WLWHIV who disengage from care are difficult to find in urban environments. Many have detectable viral loads, leading to the potential for an increased risk of MTCT. Efforts to reduce disengagement from care are critical for the successful elimination of MTCT in resource-limited settings.

Safety, Tolerability, and Pharmacokinetics of a Long-Acting Broadly Neutralizing Human Immunodeficiency Virus Type 1 (HIV-1) Monoclonal Antibody VRC01LS in HIV-1-Exposed Newborn Infants.

BACKGROUND: Perinatal human immunodeficiency virus type 1 (HIV-1) continues to occur due to barriers to effective antiretroviral prevention that might be mitigated by long-acting broadly neutralizing monoclonal antibodies (bNAbs). METHODS: An extended half-life bNAb, VRC01LS, was administered subcutaneously at 80 mg/dose after birth to HIV-1-exposed, nonbreastfed (cohort 1, n = 10) and breastfed (cohort 2, n = 11) infants. Cohort 2 received a second dose (100 mg) at 12 weeks. All received antiretroviral prophylaxis. VRC01LS levels were compared to VRC01 levels determined in a prior cohort. RESULTS: Local reactions (all grade ≤2) occurred in 67% and 20% after dose 1 and dose 2, respectively. The weight-banded dose (mean 28.8 mg/kg) of VRC01LS administered subcutaneously achieved a mean (standard deviation) plasma level of 222.3 (71.6) µg/mL by 24 hours and 44.0 (11.6) µg/mL at week 12, prior to dose 2. The preestablished target of ≥50 µg/mL was attained in 95% and 32% at weeks 8 and 12, respectively. The terminal half-life was 37-41 days. VRC01LS level after 1 dose was significantly greater (P <.002) than after a VRC01 dose (20 mg/kg). No infants acquired HIV-1. CONCLUSIONS: VRC01LS was well tolerated with pharmacokinetics that support further studies of more potent long-acting bNAbs as adjunct treatment with antiretrovirals to prevent infant HIV-1 transmission.

In-utero exposure to zidovudine-containing antiretroviral therapy and clonal hematopoiesis in HIV-exposed uninfected newborns.

OBJECTIVE: Zidovudine (ZDV) has been extensively used in pregnant women to prevent vertical transmission of HIV but few studies have evaluated potential mutagenic effects of ZDV during fetal development. DESIGN: Our study investigated clonal hematopoiesis in HIV-exposed uninfected (HEU) newborns, 94 of whom were ZDV-exposed and 91 antiretroviral therapy (ART)-unexposed and matched for potential confounding factors. METHODS: Utilizing high depth sequencing and genotyping arrays, we comprehensively examined blood samples collected during the first week after birth for potential clonal hematopoiesis associated with fetal ZDV exposure, including clonal single nucleotide variants (SNVs), small insertions and deletions (indels), and large structural copy number or copy neutral alterations. RESULTS: We observed no statistically significant difference in the number of SNVs and indels per person in ZDV-exposed children (adjusted ratio [95% confidence interval, CI] for expected number of mutations = 0.79 [0.50--1.22], P = 0.3), and no difference in the number of large structural alterations. Mutations in common clonal hematopoiesis driver genes were not found in the study population. Mutational signature analyses on SNVs detected no novel signatures unique to the ZDV-exposed children and the mutational profiles were similar between the two groups. CONCLUSION: Our results suggest that clonal hematopoiesis at levels detectable in our study is not strongly influenced by in-utero ZDV exposure; however, additional follow-up studies are needed to further evaluate the safety and potential long-term impacts of in-utero ZDV exposure in HEU children as well as better investigate genomic aberrations occurring late in pregnancy.

Pharmacokinetics and safety of early nevirapine-based antiretroviral therapy for neonates at high risk for perinatal HIV infection: a phase 1/2 proof of concept study.

BACKGROUND: With increasing intention to treat HIV as early as possible, evidence to confirm the safety and therapeutic drug concentrations of a nevirapine-based antiretroviral regimen in the early neonatal period is needed. This study aims to establish dosing of nevirapine for very early treatment of HIV-exposed neonates at high risk of HIV acquisition. METHODS: IMPAACT P1115 is a multinational phase 1/2 proof-of-concept study in which presumptive treatment for in-utero HIV infection is initiated within 48 h of birth in HIV-exposed neonates at high risk of HIV acquisition. Participants were neonates who were at least 34 weeks gestational age at birth and enrolled within 48 h of birth, born to women with presumed or confirmed HIV infection who had not received antiretrovirals during this pregnancy. The regimen consisted of two nucleoside reverse transcriptase inhibitors plus nevirapine dosed at 6 mg/kg twice daily for term neonates (≥37 weeks gestational age) or 4 mg/kg twice daily for 1 week and 6 mg/kg twice daily thereafter for preterm neonates (34 to <37 weeks gestational age). Here, we report the secondary outcomes of the study: nevirapine exposures in study weeks 1 and 2 and treatment-associated grade 3 or 4 adverse events at least possibly related to study treatment up to study week 4. A population pharmacokinetic model to assess nevirapine exposure was developed from dried blood spot and plasma nevirapine concentrations at study weeks 1 and 2. Nevirapine exposure was assessed in all patients with available blood samples and safety was assessed in all participants. This trial is registered at ClinicalTrials.gov (NCT02140255). FINDINGS: Between Jan 23, 2015, and Sept 4, 2017, 438 neonates were enrolled and included in analyses; 36 had in-utero HIV infection and 389 (89%) were born at term. Neonates without confirmed in-utero HIV infection received nevirapine for a median of 13 days (IQR 7-14). Measured dried blood spot nevirapine concentrations were higher than the minimum HIV treatment target (3 µg/mL) in 314 (90%, 95% CI 86-93) of 349 neonates at week 1 and 174 (87%, 81-91) of 201 at week 2. In Monte-Carlo simulations, week 1 nevirapine concentrations exceeded 3 µg/mL in 80% of term neonates and 82% of preterm neonates. DAIDS grade 3 or 4 adverse events at least possibly related to antiretrovirals occurred in 30 (7%, 95% CI 5-10) of 438 infants but did not lead to nevirapine cessation in any neonates; neutropenia (25 [6%] neonates) and anaemia (six [1%]) were most common. INTERPRETATION: Nevirapine at the dose studied was confirmed to be safe and provides therapeutic exposure concentrations. These data support nevirapine as a component of presumptive HIV treatment in high-risk neonates. FUNDING: National Institute of Allergy and Infectious Diseases, Eunice Kennedy Shriver National Institute of Child Health and Human Development, and the National Institute of Mental Health.

Safety and Efficacy of 48 and 96 Weeks of Alendronate in Children and Adolescents With Perinatal Human Immunodeficiency Virus Infection and Low Bone Mineral Density for Age.

No safety concerns were identified in a randomized, crossover study of alendronate/placebo in youth with perinatal HIV infection and low bone mineral density (BMD). BMD improved with 48 weeks of alendronate and continued to improve with an additional 48 weeks of therapy. Gains were largely maintained 48 weeks after stopping alendronate.

Impact of Low Birth Weight and Prematurity on Neonatal Raltegravir Pharmacokinetics: Impaact P1097.

BACKGROUND: HIV treatment of neonates requires identifying appropriate antiretroviral dosing regimens. Our aims were to characterize raltegravir elimination kinetics in low birth weight (LBW) neonates after maternal dosing and to develop a pharmacokinetic model to predict raltegravir plasma concentrations for term and preterm neonates. METHODS: Mothers living with HIV who received raltegravir during pregnancy and their LBW neonates participated in IMPAACT P1097 study. Up to 6 serial plasma samples were collected from each infant over the first 2 postnatal weeks to characterize raltegravir elimination. Safety laboratory evaluations were obtained, and infants were monitored for 6 weeks for signs of raltegravir toxicity. An integrated maternal-neonatal pharmacokinetic model was developed to predict neonatal raltegravir plasma concentrations. RESULTS: Sixteen mothers and their 18 LBW neonates were enrolled. The median (range) raltegravir elimination half-life was 24.4 (10.1-83) hours (N = 17 neonates). No adverse events related to raltegravir in utero exposure were observed. Pharmacokinetic modeling revealed that raltegravir clearance in full-term LBW neonates was well described by allometric scaling but clearance in preterm LBW neonates was better described using slower clearance maturation kinetics. Simulations suggest receipt of the current dosing recommendations in a 34-week gestation neonate would result in plasma concentrations up to 2.5-fold higher than those observed in full-term LBW infants. CONCLUSIONS: Modeling suggests that prematurity reduces raltegravir clearance and a modified raltegravir dosing regimen will be necessary to avoid elevated plasma raltegravir concentrations.

Raltegravir use and outcomes among children and adolescents living with HIV in the IeDEA global consortium.

INTRODUCTION: As integrase inhibitors become available in low- and middle-income countries (LMICs), they offer the potential to expand extremely limited treatment options available to children and adolescents. In LMICs, only small numbers have used raltegravir, primarily as part of third-line regimens. Using data from the IeDEA global consortium, we aimed to describe the characteristics of children on raltegravir-containing regimens and their outcomes. METHODS: We included data from 1994 to 2017 from children (age <18 years), from East and Southern Africa, Asia and South America, who received cART regimens containing raltegravir for ≥90 days. We describe their characteristics at raltegravir start, and their immunological and virological outcomes. RESULTS AND DISCUSSION: In total, 62 children were included, with median age at raltegravir initiation of 14.3 years (IQR 11.2 to 15.8) and median CD4 count of 276 cells/µL (IQR 68 to 494). Among 40 (65%) with drug resistance testing prior to raltegravir, 71% were resistant to at least one protease inhibitor (PI), and 32% had high-level resistance to at least one drug class. Most (n = 50; 81%) received raltegravir as part of third-line cART following PI-based regimens, and were on regimens containing four or more drugs (n = 47, 76%). By database closure, median duration on raltegravir was 2.0 years (IQR 0.8 to 3.0), 1 (1.6%) patient had died, 6 (9.7%) were lost to follow-up and 21 (34%) had discontinued raltegravir. Among 15 patients reporting reasons for stopping raltegravir, six discontinued because it was no longer available. Within one year of starting raltegravir, among 53 patients with VL measures, 40 (75%) had VL < 1000 copies/mL, and among 54 with a reported CD4 count, 45 (83%) and 36 (67%) were ≥350 and ≥500 cells/µL, respectively, with median CD4 count increasing to 517.5 cells/µL (IQR 288 to 810). CONCLUSIONS: Among children in LMICs, the initial use of raltegravir has been primarily for post PI-based cART. We found good virological and immunological outcomes despite frequent prior triple-class failure and high levels of drug resistance. Both access to raltegravir and long-term adherence to regimens with large pill-burdens remain challenging. Policies which promote earlier access to new drugs and simplify daily regimens for children and adolescents in LMICs are needed.

Fractures in children and adolescents living with perinatally acquired HIV.

BACKGROUND: Across numerous settings, bone mineral density for age and sex is lower in children/adolescents living with perinatally-acquired HIV (PHIV) compared to uninfected peers. We assessed incidences of any fracture/any long bone fracture, and osteoporosis prevalence in PHIV and HIV-exposed uninfected (PHEU) participants in the Pediatric HIV/AIDS Cohort Study (PHACS). METHODOLOGY: Lifetime history of fracture events from birth up to age 20 years was obtained by chart review and/or interview, including age at fracture, mechanism, and bone(s) fractured. Poisson regression models were fit comparing fracture incidence by HIV status adjusted for age, sex, and race, with effect modification by age (<6, ≥6 yr). RESULTS: PHIV (N = 412) were older (median 17.5 vs 16.7 yr) and more frequently reported black race (72% vs 61%) than PHEU children/adolescents (N = 206). 17% of PHIV and 12% of PHEU ever reported a fracture. Among children <6 yr, the adjusted incidence rate ratio of ≥1 fracture was higher (7.23; 95% CI 0.98, 53.51) in PHIV than PHEU, but similar among children/adolescents ≥6 years (1.20; 95% CI: 0.77, 1.87). Results were similar for long bone fracture. The most common fracture mechanisms were falling to the ground from a standing height (23.6% PHIV vs 8.8% PHEU) and sports injuries (21.3% vs 32.4%), and the most commonly fractured sites were the forearm and small bones of the wrist/hands. None of the children had osteoporosis. CONCLUSIONS: Among children/adolescents ≥6 yr of age, fractures were similar by perinatal HIV status. Prospective, targeted collection of fracture history will be necessary to determine rates of fracture as PHIV and PHEU age into adulthood. SUMMARY: Lifetime fracture history was collected in children/adolescents living with perinatally-acquired HIV (PHIV) and HIV-exposed uninfected (PHEU) children from birth up to age 20 years. Fracture incidence was higher in PHIV compared to PHEU among children <6 years old, but not among older children/adolescents.

Safety of in-utero antiretroviral exposure: neurologic outcomes in children who are HIV-exposed but uninfected.

OBJECTIVE: To evaluate whether there is an increased risk of neurologic diagnoses in children who are HIV-exposed but uninfected (CHEU) exposed in utero to specific antiretroviral medications. DESIGN: Prospective cohort study of CHEU enrolled from 2007 to 2017. METHODS: We evaluated children for neurologic case status, including microcephaly, febrile seizures, seizure disorders, ophthalmologic disorders, and other neurologic disorders. Adjusted relative risks (aRRs) were estimated for the association between in-utero antiretroviral exposure and neurologic case using log-binomial regression, accounting for potential confounders. Sensitivity analyses were conducted to evaluate robustness of findings. RESULTS: Among 3747 eligible CHEU, 231 (6.2%) met neurologic case criteria (95% CI 5.4--7%). Most eligible children (86%) were exposed in utero to combination antiretroviral regimens. In adjusted models, children exposed to efavirenz at any time during pregnancy had higher risk of neurologic case status (aRR = 1.53, 95% CI 0.94--2.51). This association was stronger when comparing efavirenz exposure at conception to no exposure during pregnancy (aRR = 1.92, 95% CI 1.09--3.36) and considering follow-up and case diagnosis only through age 2 (aRR = 2.14, 95% CI 1.11--4.12). Children exposed to didanosine at conception and during the first trimester had increased risk of neurologic case status (aRR = 2.28, 95% CI 1.07--4.87 and aRR = 2.02, 95% CI 1.01--4.04, respectively), compared with didanosine-unexposed children. Children with dolutegravir exposure had some suggestion of increased risk of neurologic case (aRR = 2.43, 95% CI 0.75--7.84), which was observed consistently across several sensitivity analyses. CONCLUSION: Efavirenz and didanosine exposure during pregnancy were associated with higher risk of neurologic abnormalities in CHEU, and dolutegravir exposure showed some suggestive associations, which warrant further monitoring.

Early antiretroviral treatment of infants to attain HIV remission.

BACKGROUND: Studies in adults and children suggested that starting antiretroviral therapy (ART) soon after infection positively influences early events in HIV infection raising the possibility that remission may be achieved in some. METHODS: We designed an analytic treatment interruption (ATI) trial to test the hypothesis that a sizable minority of HIV-infected neonates who initiated ART <14 days of birth and maintained on ART would be able to maintain viral suppression when ART was withdrawn. To yield the target cohort for this trial, 73 HIV-infected neonates identified at one hospital in Johannesburg, South Africa, were initiated on ART <14 days of birth and maintained on ART tracking viral load (VL) decline and immune recovery (clinicaltrials.gov # NCT02431975). FINDINGS: Three HIV-infected infants (4.1%) died and nine (12.3%) were lost to follow-up before 48 weeks of age. Of those surviving on study, 52.5% attained and sustained VL <50 copies/ml and half of these sustained CD4+ T-cell percentage >30% which were the primary entry criteria for the ATI trial. Proportions achieving ATI eligibility criteria were similar in the 46 infants starting ART <48 h (19.6%) to 27 infants starting 2-14 days (25.9%) (p = 0.567). INTERPRETATION: Very early ART on its own, using regimens available when the trial was designed, is insufficient to attain minimum entry criteria needed to justify our trial of ART interruption. Decisions about how quickly to start ART should be based on optimizing standard clinical outcomes rather than with the expectation that remission can be attained. FUNDING: NICHD/NIAID (U01HD080441), South African Research Chairs Initiative of DST and NRF (South Africa).

Raltegravir (RAL) in Neonates: Dosing, Pharmacokinetics (PK), and Safety in HIV-1-Exposed Neonates at Risk of Infection (IMPAACT P1110).

BACKGROUND: Adequate pharmacokinetic and safety data in neonates are lacking for most antiretroviral agents. Raltegravir is a selective HIV-1 integrase strand transfer inhibitor available in a granule formulation suitable for use in neonates and young infants as prophylaxis or treatment of HIV infection. METHODS: IMPAACT P1110 is a phase 1, multicenter, noncomparative dose-finding study of raltegravir in infants exposed to HIV-1 infection. A 2-cohort adaptive design was utilized where pharmacokinetic data from infants in cohort 1 who received 2 single doses of raltegravir 3 mg/kg were included in population modeling and simulations to guide selection of a daily dose for infants in cohort 2. RESULTS: A total of 52 infants enrolled in IMPAACT 1110: cohort 1 (N = 16) and cohort 2 (N = 36). Using simulations based on population PK modeling incorporating cohort 1 data, the following daily dosing regimen was selected for study: 1.5 mg/kg daily from birth through day 7; 3 mg/kg twice daily from days 8-28 of life; and 6 mg/kg twice daily after 4 weeks of age through 6 weeks of age. The geometric mean protocol exposure targets for AUC, Ctrough, and Cmax were met or slightly exceeded in all infants. The chosen neonatal raltegravir dosing regimen was safe and well tolerated in full-term neonates during treatment over the first 6 weeks of life and follow-up to age 24 weeks. CONCLUSIONS: Raltegravir can be safely administered to full-term infants using the daily dosing regimen studied. This regimen is not recommended for use in premature infants in a new version of P1110.

Alendronate Improves Bone Mineral Density in Children and Adolescents Perinatally Infected With Human Immunodeficiency Virus With Low Bone Mineral Density for Age.

BACKGROUND: Children and adolescents with perinatal human immunodeficiency virus (HIV) infection and with low bone mineral density (BMD) may be at higher risk of osteoporosis and fractures in later life than their uninfected peers. Bisphosphonate therapy has been shown to reduce fractures in adults with osteoporosis, but has not been formally studied in youths living with HIV. METHODS: Fifty-two children and adolescents (aged 11-24 years) perinatally infected with HIV with low lumbar spine (LS) BMD (Z score < -1.5) were randomized to receive once-weekly alendronate or placebo in a double-blind cross-over study designed to assess the safety and efficacy of 48 and 96 weeks of alendronate in the United States and Brazil. All participants received daily calcium carbonate and vitamin D supplementation and were asked to engage in regular weight-bearing exercise. Safety and efficacy are summarized for the initial 48 weeks of the trial. RESULTS: Grade 3 or higher abnormal laboratory values, signs, or symptoms developed in 5 of 32 (16%) participants on alendronate and 2 of 18 (11%) on placebo (P > .99). No cases of jaw osteonecrosis, atrial fibrillation, or nonhealing fractures were reported. Mean increases (95% confidence interval) in LS BMD over 48 weeks were significantly larger on alendronate (20% [14%-25%]) than placebo (7% [5%-9%]) (P < .001). Similar improvements were seen for whole body BMD. CONCLUSIONS: In this small study in children and adolescents perinatally infected with HIV with low LS BMD, 48 weeks of alendronate was well-tolerated, showed no safety concerns, and significantly improved LS and whole body BMD compared to participants on vitamin D/calcium supplementation and exercise alone. CLINICAL TRIALS REGISTRATION: NCT00921557.

Safety, Tolerability, and Pharmacokinetics of the Broadly Neutralizing Human Immunodeficiency Virus (HIV)-1 Monoclonal Antibody VRC01 in HIV-Exposed Newborn Infants.

BACKGROUND: Although mother-to-child human immunodeficiency virus (HIV) transmission has dramatically decreased with maternal antiretroviral therapy, breast milk transmission accounts for most of the 180 000 new infant HIV infections annually. Broadly neutralizing antibodies (bNAb) may further reduce transmission. METHODS: A Phase 1 safety and pharmacokinetic study was conducted: a single subcutaneous (SC) dose of 20 or 40 mg/kg (Dose Groups 1 and 2, respectively) of the bNAb VRC01 was administered to HIV-exposed infants soon after birth. Breastfeeding infants (Dose Group 3) received 40 mg/kg SC VRC01 after birth and then 20 mg/kg/dose SC monthly. All infants received appropriate antiretroviral prophylaxis. RESULTS: Forty infants were enrolled (21 in the United States, 19 in Africa). Subcutaneous VRC01 was safe and well tolerated with only mild-to-moderate local reactions, primarily erythema, which rapidly resolved. For multiple-dose infants, local reactions decreased with subsequent injections. VRC01 was rapidly absorbed after administration, with peak concentrations 1-6 days postdose. The 40 mg/kg dose resulted in 13 of 14 infants achieving the serum 50 micrograms (mcg)/mL target at day 28. Dose Group 3 infants maintained concentrations greater than 50 mcg/mL throughout breastfeeding. CONCLUSIONS: Subcutaneous VRC01 as single or multiple doses is safe and well tolerated in very young infants and is suitable for further study to prevent HIV transmission in infants.

Long-Term Safety and Efficacy of Dolutegravir in Treatment-Experienced Adolescents With Human Immunodeficiency Virus Infection: Results of the IMPAACT P1093 Study.

BACKGROUND: P1093 is an ongoing phase I/II multicenter open-label study of dolutegravir plus an optimized background regimen in age-defined pediatric cohorts; here we report the long-term safety and virologic efficacy outcomes for the oldest cohort. METHODS: The study enrolled human immunodeficiency virus type 1 (HIV-1)-infected treatment-experienced adolescents aged 12 to <18 years, with an HIV-1 RNA level ≥1000 copies/mL . Cumulative safety and HIV-1 RNA outcomes were assessed once the last enrolled participant reached 144 weeks of follow-up. RESULTS: Among 23 adolescents enrolled, 16 remained in the study at least 144 weeks; the median follow-up was 153 weeks (range, 55-193 weeks). Dolutegravir was well tolerated, with grade 3 clinical adverse events in 5 participants, grade 3 laboratory abnormalities in 3, and grade 4 laboratory abnormalities in 1; none of the adverse events or abnormalities were judged to be treatment related. In an-intent-to-treat analysis, an HIV-1 RNA level <400 copies/mL at week 144 was achieved in 43% (10 of 23 participants; 95% confidence interval, 23.2%-65.5%); in addition, 35% (8 of 23; 16.4%-57.3%) had an HIV-1 RNA level <50 copies/mL. Nine participants (39%) discontinued study treatment before 144 weeks, but none because of adverse events or drug intolerance. All participants with sustained virologic control had excellent adherence; most who experienced virologic failure had adherence levels <90%. HIV-1 genotypic drug resistance testing was available at time of failure from 6 participants; 1 had evolution in integrase resistance with E138T, S147G, and R263K mutations at week 192 and phenotypic dolutegravir resistance of a 5.1-fold change. CONCLUSIONS: Dolutegravir plus an optimized background regimen seemed safe, well tolerated, and efficacious in this cohort of treatment-experienced HIV-1-infected adolescents. Adherence remains problematic in this population. CLINICAL TRIALS REGISTRATION: NCT01302847.