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

Barriers to childhood asthma care in sub-Saharan Africa: a multicountry qualitative study with children and their caregivers.

OBJECTIVES: This study identifies barriers and provides recommendations to improve asthma care in children across sub-Saharan Africa, where qualitative data is lacking despite high rates. DESIGN: One of the aims of our National Institute for Health Research global health research group 'Achieving Control of Asthma in Children in Africa' was to use qualitative thematic analysis of transcribed audio recordings from focus group discussions (FGDs) to describe barriers to achieving good asthma control. SETTING: Schools in Blantyre (Malawi), Lagos (Nigeria), Durban (South Africa), Kampala (Uganda) and Harare (Zimbabwe). PARTICIPANTS: Children (n=136), 12-14 years with either asthma symptoms or a diagnosis and their caregivers participated in 39 FGDs. All were recruited using asthma control questions from the Global Asthma Network survey. RESULTS: There were four key themes identified: (1) Poor understanding, (2) difficulties experienced with being diagnosed, (3) challenges with caring for children experiencing an acute asthma episode and (4) suboptimal uptake and use of prescribed medicines. An inadequate understanding of environmental triggers, a hesitancy in using metred dose inhalers and a preference for oral and alternate medications were identified as barriers. In addition, limited access to healthcare with delays in diagnosis and an inability to cope with expected lifestyle changes was reported. Based on these findings, we recommend tailored education to promote access to and acceptance of metred dose inhalers, including advocating for access to a single therapeutic, preventative and treatment option. Furthermore, healthcare systems should have simpler diagnostic pathways and easier emergency access for asthma. CONCLUSIONS: In a continent with rapidly increasing levels of poorly controlled asthma, we identified multiple barriers to achieving good asthma control along the trajectory of care. Exploration of these barriers reveals several generalisable recommendations that should modify asthma care plans and potentially transform asthma care in Africa. TRIAL REGISTRATION NUMBER: 269211

Brief Report: Suboptimal Lopinavir Exposure in Infants on Rifampicin Treatment Receiving Double-dosed or Semisuperboosted Lopinavir/Ritonavir: Time for a Change.

BACKGROUND: Although super-boosted lopinavir/ritonavir (LPV/r; ratio 4:4 instead of 4:1) is recommended for infants living with HIV and receiving concomitant rifampicin, in clinical practice, many different LPV/r dosing strategies are applied due to poor availability of pediatric separate ritonavir formulations needed to superboost. We evaluated LPV pharmacokinetics in infants with HIV receiving LPV/r dosed according to local guidelines in various sub-Saharan African countries with or without rifampicin-based tuberculosis (TB) treatment. METHODS: This was a 2-arm pharmacokinetic substudy nested within the EMPIRICAL trial (#NCT03915366). Infants aged 1-12 months recruited into the main study were administered LPV/r according to local guidelines and drug availability either with or without rifampicin-based TB treatment; during rifampicin cotreatment, they received double-dosed (ratio 8:2) or semisuperboosted LPV/r (adding a ritonavir 100 mg crushed tablet to the evening LPV/r dose). Six blood samples were taken over 12 hours after intake of LPV/r. RESULTS: In total, 14/16 included infants had evaluable pharmacokinetic curves; 9/14 had rifampicin cotreatment (5 received double-dosed and 4 semisuperboosted LPV/r). The median (IQR) age was 6.4 months (5.4-9.8), weight 6.0 kg (5.2-6.8), and 10/14 were male. Of those receiving rifampicin, 6/9 infants (67%) had LPV Ctrough <1.0 mg/L compared with 1/5 (20%) in the control arm. LPV apparent oral clearance was 3.3-fold higher for infants receiving rifampicin. CONCLUSION: Double-dosed or semisuperboosted LPV/r for infants aged 1-12 months receiving rifampicin resulted in substantial proportions of subtherapeutic LPV levels. There is an urgent need for data on alternative antiretroviral regimens in infants with HIV/TB coinfection, including twice-daily dolutegravir

Dolutegravir dosing for children with HIV weighing less than 20 kg: pharmacokinetic and safety substudies nested in the open-label, multicentre, randomised, non-inferiority ODYSSEY trial.

BACKGROUND: Dolutegravir-based antiretroviral therapy is a preferred first-line treatment for adults and children living with HIV; however, very little pharmacokinetic data for dolutegravir use are available in young children. We therefore aimed to evaluate dolutegravir dosing and safety in children weighing 3 kg to less than 20 kg by assessing pharmacokinetic parameters and safety data in children taking dolutegravir within the ODYSSEY trial. METHODS: We did pharmacokinetic substudies nested within the open-label, multicentre, randomised, non-inferiority ODYSSEY trial. We enrolled children from seven research centres in South Africa, Uganda, and Zimbabwe. Children weighing 3 kg to less than 14 kg received 5 mg dispersible tablets of dolutegravir according to WHO weight bands: 5 mg for children weighing 3 kg to less than 6 kg and younger than 6 months, 10 mg for children weighing 3 kg to less than 6 kg and aged 6 months or older, 15 mg for children weighing 6 kg to less than 10 kg, and 20 mg for children weighing 10 kg to less than 14 kg. Children weighing 14 kg to less than 20 kg received a 25 mg film-coated tablet once per day early in the trial or 25 mg dispersible tablets (five 5 mg tablets once per day) later in the trial. A minimum of eight children per weight band or dose was targeted for 24 h pharmacokinetic profiling at steady state. The primary pharmacokinetic parameter was the trough concentration 24 h after observed dolutegravir intake (Ctrough). Pharmacokinetic targets were based on adult dolutegravir Ctrough and the 90% effective concentration (EC90; ie, 0·32 mg/L). Safety was evaluated in eligible children consenting to pharmacokinetic substudies. FINDINGS: Between May 25, 2017, and Aug 15, 2019, we enrolled 72 children aged between 3 months and 11 years. 71 children were included in the safety population and 55 (76%) of 72 children contributed 65 evaluable pharmacokinetic profiles. Geometric mean Ctrough in children on dispersible tablets in weight bands between 3 kg and less than 20 kg ranged between 0·53-0·87 mg/L, comparable to the adult geometric mean Ctrough of 0·83 mg/L. Variability was high with coefficient of variation percentages ranging between 50% and 150% compared with 26% in adults. Ctrough below EC90 was observed in four (31%) of 13 children weighing 6 kg to less than 10 kg taking 15 mg dispersible tablets, and four (21%) of 19 weighing 14 kg to less than 20 kg taking 25 mg film-coated tablets. The lowest geometric mean Ctrough of 0·44 mg/L was observed in children weighing 14 kg to less than 20 kg on 25 mg film-coated tablets. Exposures were 1·7-2·0 times higher on 25 mg dispersible tablets versus 25 mg film-coated tablets. 19 (27%) of 71 children had 29 reportable grade 3 or higher adverse events (13 serious adverse events, including two deaths), none of which were related to dolutegravir. INTERPRETATION: Weight-band dosing of paediatric dolutegravir dispersible tablets provides appropriate drug exposure in most children weighing 3 kg to less than 20 kg, with no safety signal. 25 mg film-coated tablets did not achieve pharmacokinetic parameters in children weighing 14 kg to less than 20 kg, which were comparable to adults, suggesting dosing with dispersible tablets is preferable or a higher film-coated tablet dose is required. FUNDING: Paediatric European Network for Treatment of AIDS Foundation, ViiV Healthcare, and UK Medical Research Council

Neuropsychiatric manifestations and sleep disturbances with dolutegravir-based antiretroviral therapy versus standard of care in children and adolescents: a secondary analysis of the ODYSSEY trial

BACKGROUND: Cohort studies in adults with HIV showed that dolutegravir was associated with neuropsychiatric adverse events and sleep problems, yet data are scarce in children and adolescents. We aimed to evaluate neuropsychiatric manifestations in children and adolescents treated with dolutegravir-based treatment versus alternative antiretroviral therapy. METHODS: This is a secondary analysis of ODYSSEY, an open-label, multicentre, randomised, non-inferiority trial, in which adolescents and children initiating first-line or second-line antiretroviral therapy were randomly assigned 1:1 to dolutegravir-based treatment or standard-of-care treatment. We assessed neuropsychiatric adverse events (reported by clinicians) and responses to the mood and sleep questionnaires (reported by the participant or their carer) in both groups. We compared the proportions of patients with neuropsychiatric adverse events (neurological, psychiatric, and total), time to first neuropsychiatric adverse event, and participant-reported responses to questionnaires capturing issues with mood, suicidal thoughts, and sleep problems. FINDINGS: Between Sept 20, 2016, and June 22, 2018, 707 participants were enrolled, of whom 345 (49%) were female and 362 (51%) were male, and 623 (88%) were Black-African. Of 707 participants, 350 (50%) were randomly assigned to dolutegravir-based antiretroviral therapy and 357 (50%) to non-dolutegravir-based standard-of-care. 311 (44%) of 707 participants started first-line antiretroviral therapy (ODYSSEY-A; 145 [92%] of 157 participants had efavirenz-based therapy in the standard-of-care group), and 396 (56%) of 707 started second-line therapy (ODYSSEY-B; 195 [98%] of 200 had protease inhibitor-based therapy in the standard-of-care group). During follow-up (median 142 weeks, IQR 124–159), 23 participants had 31 neuropsychiatric adverse events (15 in the dolutegravir group and eight in the standard-of-care group; difference in proportion of participants with ≥1 event p=0·13). 11 participants had one or more neurological events (six and five; p=0·74) and 14 participants had one or more psychiatric events (ten and four; p=0·097). Among 14 participants with psychiatric events, eight participants in the dolutegravir group and four in standard-of-care group had suicidal ideation or behaviour. More participants in the dolutegravir group than the standard-of-care group reported symptoms of self-harm (eight vs one; p=0·025), life not worth living (17 vs five; p=0·0091), or suicidal thoughts (13 vs none; p=0·0006) at one or more follow-up visits. Most reports were transient. There were no differences by treatment group in low mood or feeling sad, problems concentrating, feeling worried or feeling angry or aggressive, sleep problems, or sleep quality. INTERPRETATION: The numbers of neuropsychiatric adverse events and reported neuropsychiatric symptoms were low. However, numerically more participants had psychiatric events and reported suicidality ideation in the dolutegravir group than the standard-of-care group. These differences should be interpreted with caution in an open-label trial. Clinicians and policy makers should consider including suicidality screening of children or adolescents receiving dolutegravir

Dolutegravir twice-daily dosing in children with HIV-associated tuberculosis: a pharmacokinetic and safety study within the open-label, multicentre, randomised, non-inferiority ODYSSEY trial

Background: Children with HIV-associated tuberculosis (TB) have few antiretroviral therapy (ART) options. We aimed to evaluate the safety and pharmacokinetics of dolutegravir twice-daily dosing in children receiving rifampicin for HIV-associated TB. Methods: We nested a two-period, fixed-order pharmacokinetic substudy within the open-label, multicentre, randomised, controlled, non-inferiority ODYSSEY trial at research centres in South Africa, Uganda, and Zimbabwe. Children (aged 4 weeks to <18 years) with HIV-associated TB who were receiving rifampicin and twice-daily dolutegravir were eligible for inclusion. We did a 12-h pharmacokinetic profile on rifampicin and twice-daily dolutegravir and a 24-h profile on once-daily dolutegravir. Geometric mean ratios for trough plasma concentration (Ctrough), area under the plasma concentration time curve from 0 h to 24 h after dosing (AUC0–24 h), and maximum plasma concentration (Cmax) were used to compare dolutegravir concentrations between substudy days. We assessed rifampicin Cmax on the first substudy day. All children within ODYSSEY with HIV-associated TB who received rifampicin and twice-daily dolutegravir were included in the safety analysis. We described adverse events reported from starting twice-daily dolutegravir to 30 days after returning to once-daily dolutegravir. This trial is registered with ClinicalTrials.gov (NCT02259127), EudraCT (2014–002632-14), and the ISRCTN registry (ISRCTN91737921). Findings: Between Sept 20, 2016, and June 28, 2021, 37 children with HIV-associated TB (median age 11·9 years [range 0·4–17·6], 19 [51%] were female and 18 [49%] were male, 36 [97%] in Africa and one [3%] in Thailand) received rifampicin with twice-daily dolutegravir and were included in the safety analysis. 20 (54%) of 37 children enrolled in the pharmacokinetic substudy, 14 of whom contributed at least one evaluable pharmacokinetic curve for dolutegravir, including 12 who had within-participant comparisons. Geometric mean ratios for rifampicin and twice-daily dolutegravir versus once-daily dolutegravir were 1·51 (90% CI 1·08–2·11) for Ctrough, 1·23 (0·99–1·53) for AUC0–24 h, and 0·94 (0·76–1·16) for Cmax. Individual dolutegravir Ctrough concentrations were higher than the 90% effective concentration (ie, 0·32 mg/L) in all children receiving rifampicin and twice-daily dolutegravir. Of 18 children with evaluable rifampicin concentrations, 15 (83%) had a Cmax of less than the optimal target concentration of 8 mg/L. Rifampicin geometric mean Cmax was 5·1 mg/L (coefficient of variation 71%). During a median follow-up of 31 weeks (IQR 30–40), 15 grade 3 or higher adverse events occurred among 11 (30%) of 37 children, ten serious adverse events occurred among eight (22%) children, including two deaths (one tuberculosis-related death, one death due to traumatic injury); no adverse events, including deaths, were considered related to dolutegravir. Interpretation: Twice-daily dolutegravir was shown to be safe and sufficient to overcome the rifampicin enzyme-inducing effect in children, and could provide a practical ART option for children with HIV-associated TB

Option A improved HIV-free infant survival and mother to child HIV transmission at 9–18 months in Zimbabwe

OBJECTIVE: We evaluated the impact of Option A on HIV-free infant survival and mother-to-child transmission (MTCT) in Zimbabwe. DESIGN: Serial cross-sectional community-based serosurveys. METHODS: We analyzed serosurvey data collected in 2012 and 2014 among mother-infant pairs from catchment areas (CAs) of 132 health facilities from 5 of 10 provinces in Zimbabwe. Eligible infants (alive or deceased) were born 9–18 months before each survey to mothers ≥16 years old. We randomly selected mother-infant pairs and conducted questionnaires, verbal autopsies and collected blood samples. We estimated: 1) the HIV-free infant survival and MTCT rate within each CA and compared the 2012 and 2014 estimates using a paired t-test, 2) number of HIV infections averted due to the intervention. RESULTS: We analyzed 7,249 mother-infant pairs with viable maternal specimens collected in 2012 and 8,551 in 2014. The mean difference in the CA-level MTCT between 2014 and 2012 was −5.2 percentage points (95% confidence interval (CI)=−8.1, −2.3, p<0.001). The mean difference in the CA-level HIV-free survival was 5.5 percentage points (95%CI=2.6,8.5, p<0.001). Between 2012 and 2014, 1,779 infant infections were averted compared to the pre-Option A regimen. The association between HIV-free infant survival and duration of Option A implementation was not significant at the multivariate level (p=0.093). CONCLUSIONS: We found a substantial and statistically significant increase in HIV-free survival and decrease in MTCT among infants aged 9–18 months following Option A rollout in Zimbabwe. This is the only impact evaluation of Option A and shows the effectiveness of Option A and Zimbabwe’s remarkable progress towards eMTCT

Option A improved HIV-free infant survival and mother to child HIV transmission at 9–18 months in Zimbabwe

ObjectiveWe evaluated the impact of Option A on HIV-free infant survival and mother-to-child transmission (MTCT) in Zimbabwe.DesignSerial cross-sectional community-based serosurveys.MethodsWe analyzed serosurvey data collected in 2012 and 2014 among mother-infant pairs from catchment areas of 132 health facilities from five of 10 provinces in Zimbabwe. Eligible infants (alive or deceased) were born 9-18 months before each survey to mothers at least 16 years old. We randomly selected mother-infant pairs and conducted questionnaires, verbal autopsies, and collected blood samples. We estimated the HIV-free infant survival and MTCT rate within each catchment area and compared the 2012 and 2014 estimates using a paired t test and number of HIV infections averted because of the intervention.ResultsWe analyzed 7249 mother-infant pairs with viable maternal specimens collected in 2012 and 8551 in 2014. The mean difference in the catchment area level MTCT between 2014 and 2012 was -5.2 percentage points (95% confidence interval = -8.1, -2.3, P &lt; 0.001). The mean difference in the catchment area level HIV-free survival was 5.5 percentage points (95% confidence interval = 2.6, 8.5, P &lt; 0.001). Between 2012 and 2014, 1779 infant infections were averted compared with the pre-Option A regimen. The association between HIV-free infant survival and duration of Option A implementation was NS at the multivariate level (P = 0.093).ConclusionWe found a substantial and statistically significant increase in HIV-free survival and decrease in MTCT among infants aged 9-18 months following Option A rollout in Zimbabwe. This is the only evaluation of Option A and shows the effectiveness of Option A and Zimbabwe's remarkable progress toward eMTCT

Option A improved HIV-free infant survival and mother to child HIV transmission at 9–18 months in Zimbabwe

OBJECTIVE: We evaluated the impact of Option A on HIV-free infant survival and mother-to-child transmission (MTCT) in Zimbabwe. DESIGN: Serial cross-sectional community-based serosurveys. METHODS: We analyzed serosurvey data collected in 2012 and 2014 among mother-infant pairs from catchment areas (CAs) of 132 health facilities from 5 of 10 provinces in Zimbabwe. Eligible infants (alive or deceased) were born 9–18 months before each survey to mothers ≥16 years old. We randomly selected mother-infant pairs and conducted questionnaires, verbal autopsies and collected blood samples. We estimated: 1) the HIV-free infant survival and MTCT rate within each CA and compared the 2012 and 2014 estimates using a paired t-test, 2) number of HIV infections averted due to the intervention. RESULTS: We analyzed 7,249 mother-infant pairs with viable maternal specimens collected in 2012 and 8,551 in 2014. The mean difference in the CA-level MTCT between 2014 and 2012 was −5.2 percentage points (95% confidence interval (CI)=−8.1, −2.3, p<0.001). The mean difference in the CA-level HIV-free survival was 5.5 percentage points (95%CI=2.6,8.5, p<0.001). Between 2012 and 2014, 1,779 infant infections were averted compared to the pre-Option A regimen. The association between HIV-free infant survival and duration of Option A implementation was not significant at the multivariate level (p=0.093). CONCLUSIONS: We found a substantial and statistically significant increase in HIV-free survival and decrease in MTCT among infants aged 9–18 months following Option A rollout in Zimbabwe. This is the only impact evaluation of Option A and shows the effectiveness of Option A and Zimbabwe’s remarkable progress towards eMTCT

Evaluating the Impact of Zimbabwe's Prevention of Mother-to-Child HIV Transmission Program: Population-Level Estimates of HIV-Free Infant Survival Pre-Option A.

We estimated HIV-free infant survival and mother-to-child HIV transmission (MTCT) rates in Zimbabwe, some of the first community-based estimates from a UNAIDS priority country.In 2012 we surveyed mother-infant pairs residing in the catchment areas of 157 health facilities randomly selected from 5 of 10 provinces in Zimbabwe. Enrolled infants were born 9-18 months before the survey. We collected questionnaires, blood samples for HIV testing, and verbal autopsies for deceased mothers/infants. Estimates were assessed among i) all HIV-exposed infants, as part of an impact evaluation of Option A of the 2010 WHO guidelines (rolled out in Zimbabwe in 2011), and ii) the subgroup of infants unexposed to Option A. We compared province-level MTCT rates measured among women in the community with MTCT rates measured using program monitoring data from facilities serving those communities.Among 8568 women with known HIV serostatus, 1107 (12.9%) were HIV-infected. Among all HIV-exposed infants, HIV-free infant survival was 90.9% (95% confidence interval (CI): 88.7-92.7) and MTCT was 8.8% (95% CI: 6.9-11.1). Sixty-six percent of HIV-exposed infants were still breastfeeding. Among the 762 infants born before Option A was implemented, 90.5% (95% CI: 88.1-92.5) were alive and HIV-uninfected at 9-18 months of age, and 9.1% (95%CI: 7.1-11.7) were HIV-infected. In four provinces, the community-based MTCT rate was higher than the facility-based MTCT rate. In Harare, the community and facility-based rates were 6.0% and 9.1%, respectively.By 2012 Zimbabwe had made substantial progress towards the elimination of MTCT. Our HIV-free infant survival and MTCT estimates capture HIV transmissions during pregnancy, delivery and breastfeeding regardless of whether or not mothers accessed health services. These estimates also provide a baseline against which to measure the impact of Option A guidelines (and subsequently Option B+)