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Background: Preterm born infants are at risk for brain injury and subsequent developmental delay. Treatment options are limited, but optimizing postnatal nutrition may improve brain- and neurodevelopment in these infants. In pre-clinical animal models, combined supplementation of docosahexaenoic acid (DHA), choline, and uridine-5-monophosphate (UMP) have shown to support neuronal membrane formation. In two randomized controlled pilot trials, supplementation with the investigational product was associated with clinically meaningful improvements in cognitive, attention, and language scores. The present study aims to assess the effect of a similar nutritional intervention on brain development and subsequent neurodevelopmental outcome in infants born very and extremely preterm., Methods: This is a randomized, placebo-controlled, double-blinded, parallel-group, multi-center trial. A total of 130 infants, born at less than 30 weeks of gestation, will be randomized to receive a test or control product between term-equivalent age and 12 months corrected age (CA). The test product is a nutrient blend containing DHA, choline, and UMP amongst others. The control product contains only fractions of the active components. Both products are isocaloric powder supplements which can be added to milk and solid feeds. The primary outcome parameter is white matter integrity at three months CA, assessed using diffusion-tensor imaging (DTI) on MRI scanning. Secondary outcome parameters include volumetric brain development, cortical thickness, cortical folding, the metabolic and biochemical status of the brain, and product safety. Additionally, language, cognitive, motor, and behavioral development will be assessed at 12 and 24 months CA, using the Bayley Scales of Infant Development III and digital questionnaires (Dutch version of the Communicative Development Inventories (N-CDI), Ages and Stages Questionnaire 4 (ASQ-4), and Parent Report of Children's Abilities - Revised (PARCA-R))., Discussion: The investigated nutritional intervention is hypothesized to promote brain development and subsequent neurodevelopmental outcome in preterm born infants who have an inherent risk of developmental delay. Moreover, this innovative study may give rise to new treatment possibilities and improvements in routine clinical care., Trial Registration: WHO International Clinical Trials Registry: NL-OMON56181 (registration assigned October 28, 2021)., (© 2024. The Author(s).)

Aims: Little is known about the population pharmacokinetics (PPK) of vancomycin in neonates with perinatal asphyxia treated with therapeutic hypothermia (TH). We aimed to describe the PPK of vancomycin and propose an initial dosing regimen for the first 48 h of treatment with pharmacokinetic/pharmacodynamic target attainment., Methods: Neonates with perinatal asphyxia treated with TH were included from birth until Day 6 in a multicentre prospective cohort study. A vancomycin PPK model was constructed using nonlinear mixed-effects modelling. The model was used to evaluate published dosing guidelines with regard to pharmacokinetic/pharmacodynamic target attainment. The area under the curve/minimal inhibitory concentration ratio of 400-600 mg*h/L was used as target range., Results: Sixteen patients received vancomycin (median gestational age: 41 [range: 38-42] weeks, postnatal age: 4.4 [2.5-5.5] days, birth weight: 3.5 [2.3-4.7] kg), and 112 vancomycin plasma concentrations were available. Most samples (79%) were collected during the rewarming and normothermic phase, as vancomycin was rarely initiated during the hypothermic phase due to its nonempirical use. An allometrically scaled 1-compartment model showed the best fit. Vancomycin clearance was 0.17 L/h, lower than literature values for term neonates of 3.5 kg without perinatal asphyxia (range: 0.20-0.32 L/h). Volume of distribution was similar. Published dosing regimens led to overexposure within 24 h of treatment. A loading dose of 10 mg/kg followed by 24 mg/kg/day in 4 doses resulted in target attainment., Conclusion: Results of this study suggest that vancomycin clearance is reduced in term neonates with perinatal asphyxia treated with TH. Lower dosing regimens should be considered followed by model-informed precision dosing., (© 2024 The Authors. British Journal of Clinical Pharmacology published by John Wiley & Sons Ltd on behalf of British Pharmacological Society.)

Background: Model validation procedures are crucial when population pharmacokinetic (PK) models are used to develop dosing algorithms and to perform model-informed precision dosing. We have previously published a population PK model describing the PK of gentamicin in term neonates with perinatal asphyxia during controlled therapeutic hypothermia (TH), which showed altered gentamicin clearance during the hypothermic phase dependent on gestational age and weight. In this study, the predictive performance and generalizability of this model were assessed using an independent data set of neonates with perinatal asphyxia undergoing controlled TH., Methods: The external data set contained a subset of neonates included in the prospective observational multicenter PharmaCool Study. Predictive performance was assessed by visually inspecting observed-versus-predicted concentration plots and calculating bias and precision. In addition, simulation-based diagnostics, model refitting, and bootstrap analyses were performed., Results: The external data set included 323 gentamicin concentrations of 39 neonates. Both the model-building and external data set included neonates from multiple centers. The original gentamicin PK model predicted the observed gentamicin concentrations with adequate accuracy and precision during all phases of controlled TH. Model appropriateness was confirmed with prediction-corrected visual predictive checks and normalized prediction distribution error analyses. Model refitting to the merged data set (n = 86 neonates with 935 samples) showed accurate estimation of PK parameters., Conclusions: The results of this external validation study justify the generalizability of the gentamicin dosing recommendations made in the original study for neonates with perinatal asphyxia undergoing controlled TH (5 mg/kg every 36 or 24 h with gestational age 36-41 and 42 wk, respectively) and its applicability in model-informed precision dosing., Competing Interests: The authors declare no conflict of interest., (Copyright © 2024 The Author(s). Published by Wolters Kluwer Health, Inc. on behalf of the International Association of Therapeutic Drug Monitoring and Clinical Toxicology.)

Ceftazidime is an antibiotic commonly used to treat bacterial infections in term neonates undergoing controlled therapeutic hypothermia (TH) for hypoxic-ischemic encephalopathy after perinatal asphyxia. We aimed to describe the population pharmacokinetics (PK) of ceftazidime in asphyxiated neonates during hypothermia, rewarming, and normothermia and propose a population-based rational dosing regimen with optimal PK/pharmacodynamic (PD) target attainment. Data were collected in the PharmaCool prospective observational multicenter study. A population PK model was constructed, and the probability of target attainment (PTA) was assessed during all phases of controlled TH using targets of 100% of the time that the concentration in the blood exceeds the MIC ( T >MIC ) (for efficacy purposes and 100% T >4×MIC and 100% T >5×MIC to prevent resistance). A total of 35 patients with 338 ceftazidime concentrations were included. An allometrically scaled one-compartment model with postnatal age and body temperature as covariates on clearance was constructed. For a typical patient receiving the current dose of 100 mg/kg of body weight/day in 2 doses and assuming a worst-case MIC of 8 mg/L for Pseudomonas aeruginosa, the PTA was 99.7% for 100% T >MIC during hypothermia (33.7°C; postnatal age [PNA] of 2 days). The PTA decreased to 87.7% for 100% T >MIC during normothermia (36.7°C; PNA of 5 days). Therefore, a dosing regimen of 100 mg/kg/day in 2 doses during hypothermia and rewarming and 150 mg/kg/day in 3 doses during the following normothermic phase is advised. Higher-dosing regimens (150 mg/kg/day in 3 doses during hypothermia and 200 mg/kg/day in 4 doses during normothermia) could be considered when achievements of 100% T >4×MIC and 100% T >5×MIC are desired., Competing Interests: The authors declare no conflict of interest.

Background: Cyclooxygenase inhibitors are commonly used in infants with patent ductus arteriosus (PDA), but the benefit of these drugs is uncertain., Methods: In this multicenter, noninferiority trial, we randomly assigned infants with echocardiographically confirmed PDA (diameter, >1.5 mm, with left-to-right shunting) who were extremely preterm (<28 weeks' gestational age) to receive either expectant management or early ibuprofen treatment. The composite primary outcome included necrotizing enterocolitis (Bell's stage IIa or higher), moderate to severe bronchopulmonary dysplasia, or death at 36 weeks' postmenstrual age. The noninferiority of expectant management as compared with early ibuprofen treatment was defined as an absolute risk difference with an upper boundary of the one-sided 95% confidence interval of less than 10 percentage points., Results: A total of 273 infants underwent randomization. The median gestational age was 26 weeks, and the median birth weight was 845 g. A primary-outcome event occurred in 63 of 136 infants (46.3%) in the expectant-management group and in 87 of 137 (63.5%) in the early-ibuprofen group (absolute risk difference, -17.2 percentage points; upper boundary of the one-sided 95% confidence interval [CI], -7.4; P<0.001 for noninferiority). Necrotizing enterocolitis occurred in 24 of 136 infants (17.6%) in the expectant-management group and in 21 of 137 (15.3%) in the early-ibuprofen group (absolute risk difference, 2.3 percentage points; two-sided 95% CI, -6.5 to 11.1); bronchopulmonary dysplasia occurred in 39 of 117 infants (33.3%) and in 57 of 112 (50.9%), respectively (absolute risk difference, -17.6 percentage points; two-sided 95% CI, -30.2 to -5.0). Death occurred in 19 of 136 infants (14.0%) and in 25 of 137 (18.2%), respectively (absolute risk difference, -4.3 percentage points; two-sided 95% CI, -13.0 to 4.4). Rates of other adverse outcomes were similar in the two groups., Conclusions: Expectant management for PDA in extremely premature infants was noninferior to early ibuprofen treatment with respect to necrotizing enterocolitis, bronchopulmonary dysplasia, or death at 36 weeks' postmenstrual age. (Funded by the Netherlands Organization for Health Research and Development and the Belgian Health Care Knowledge Center; BeNeDuctus ClinicalTrials.gov number, NCT02884219; EudraCT number, 2017-001376-28.)., (Copyright © 2022 Massachusetts Medical Society.)

Background: Controversy exists about the optimal management of a patent ductus arteriosus (PDA) in preterm infants. A persistent PDA is associated with neonatal mortality and morbidity, but causality remains unproven. Although both pharmacological and/or surgical treatment are effective in PDA closure, this has not resulted in an improved neonatal outcome. In most preterm infants, a PDA will eventually close spontaneously, hence PDA treatment potentially increases the risk of iatrogenic adverse effects. Therefore, expectant management is gaining interest, even in the absence of convincing evidence to support this strategy., Methods/design: The BeNeDuctus trial is a multicentre, randomised, non-inferiority trial assessing early pharmacological treatment (24-72 h postnatal age) with ibuprofen versus expectant management of PDA in preterm infants in Europe. Preterm infants with a gestational age of less than 28 weeks and an echocardiographic-confirmed PDA with a transductal diameter of > 1.5 mm are randomly allocated to early pharmacological treatment with ibuprofen or expectant management after parental informed consent. The primary outcome measure is the composite outcome of mortality, and/or necrotizing enterocolitis Bell stage ≥ IIa, and/or bronchopulmonary dysplasia, all established at a postmenstrual age of 36 weeks. Secondary short-term outcomes are comorbidity and adverse events assessed during hospitalization and long-term neurodevelopmental outcome assessed at a corrected age of 2 years. This statistical analysis plan focusses on the short-term outcome and is written and submitted without knowledge of the data., Trial Registration: ClinicalTrials.gov NTR5479. Registered on October 19, 2015, with the Dutch Trial Registry, sponsored by the United States National Library of Medicine Clinicaltrials.gov NCT02884219 (registered May 2016) and the European Clinical Trials Database EudraCT 2017-001376-28., (© 2021. The Author(s).)

Drug dosing in encephalopathic neonates treated with therapeutic hypothermia is challenging; exposure is dependent on body size and maturation but can also be influenced by factors related to disease and treatment. A better understanding of underlying pharmacokinetic principles is essential to guide drug dosing in this population. The prospective multicenter cohort study PharmaCool was designed to investigate the pharmacokinetics of commonly used drugs in neonatal encephalopathy. In the present study, all data obtained in the PharmaCool study were combined to study the structural system specific effects of body size, maturation, recovery of organ function, and temperature on drug clearance using nonlinear mixed effects modeling. Data collected during the first 5 days of life from 192 neonates treated with therapeutic hypothermia were included. An integrated population pharmacokinetic model of seven drugs (morphine, midazolam, lidocaine, phenobarbital, amoxicillin, gentamicin, and benzylpenicillin) and five metabolites (morphine-3-glucuronide, morphine-6-glucuronide, 1-hydroxymidazolam, hydroxymidazolam glucuronide, and monoethylglycylxylidide) was successfully developed based on previously developed models for the individual drugs. For all compounds, body size was related to clearance using allometric relationships and maturation was described with gestational age in a fixed sigmoidal Hill equation. Organ recovery after birth was incorporated using postnatal age. Clearance increased by 1.23%/hours of life (95% confidence interval (CI) 1.03-1.43) and by 0.54%/hours of life (95% CI 0.371-0.750) for high and intermediate clearance compounds, respectively. Therapeutic hypothermia reduced clearance of intermediate clearance compounds only, by 6.83%/°C (95% CI 5.16%/°C-8.34%/°C). This integrated model can be used to facilitate drug dosing and future pharmacokinetic studies in this population., (© 2020 The Authors. Clinical Pharmacology & Therapeutics published by Wiley Periodicals LLC on behalf of American Society for Clinical Pharmacology and Therapeutics.)

Background: Worldwide, many newborns who are preterm, small or large for gestational age, or born to mothers with diabetes are screened for hypoglycemia, with a goal of preventing brain injury. However, there is no consensus on a treatment threshold that is safe but also avoids overtreatment., Methods: In a multicenter, randomized, noninferiority trial involving 689 otherwise healthy newborns born at 35 weeks of gestation or later and identified as being at risk for hypoglycemia, we compared two threshold values for treatment of asymptomatic moderate hypoglycemia. We sought to determine whether a management strategy that used a lower threshold (treatment administered at a glucose concentration of <36 mg per deciliter [2.0 mmol per liter]) would be noninferior to a traditional threshold (treatment at a glucose concentration of <47 mg per deciliter [2.6 mmol per liter]) with respect to psychomotor development at 18 months, assessed with the Bayley Scales of Infant and Toddler Development, third edition, Dutch version (Bayley-III-NL; scores range from 50 to 150 [mean {±SD}, 100±15]), with higher scores indicating more advanced development and 7.5 points (one half the SD) representing a clinically important difference). The lower threshold would be considered noninferior if scores were less than 7.5 points lower than scores in the traditional-threshold group., Results: Bayley-III-NL scores were assessed in 287 of the 348 children (82.5%) in the lower-threshold group and in 295 of the 341 children (86.5%) in the traditional-threshold group. Cognitive and motor outcome scores were similar in the two groups (mean scores [±SE], 102.9±0.7 [cognitive] and 104.6±0.7 [motor] in the lower-threshold group and 102.2±0.7 [cognitive] and 104.9±0.7 [motor] in the traditional-threshold group). The prespecified inferiority limit was not crossed. The mean glucose concentration was 57±0.4 mg per deciliter (3.2±0.02 mmol per liter) in the lower-threshold group and 61±0.5 mg per deciliter (3.4±0.03 mmol per liter) in the traditional-threshold group. Fewer and less severe hypoglycemic episodes occurred in the traditional-threshold group, but that group had more invasive diagnostic and treatment interventions. Serious adverse events in the lower-threshold group included convulsions (during normoglycemia) in one newborn and one death., Conclusions: In otherwise healthy newborns with asymptomatic moderate hypoglycemia, a lower glucose treatment threshold (36 mg per deciliter) was noninferior to a traditional threshold (47 mg per deciliter) with regard to psychomotor development at 18 months. (Funded by the Netherlands Organization for Health Research and Development; HypoEXIT Current Controlled Trials number, ISRCTN79705768.)., (Copyright © 2020 Massachusetts Medical Society.)

Aims: Lidocaine is used to treat neonatal seizures refractory to other anticonvulsants. It is effective, but also associated with cardiac toxicity. Previous studies have reported on the pharmacokinetics of lidocaine in preterm and term neonates and proposed a dosing regimen for effective and safe lidocaine use. The objective of this study was to evaluate the previously developed pharmacokinetic models and dosing regimen. As a secondary objective, lidocaine effectiveness and safety were assessed., Methods: Data from preterm neonates and (near-)term neonates with and without therapeutic hypothermia receiving lidocaine were included. Pharmacokinetic analyses were performed using non-linear mixed effects modelling. Simulations were performed to evaluate the proposed dosing regimen. Lidocaine was considered effective if no additional anticonvulsant was required and safe if no cardiac adverse events occurred., Results: Data were available for 159 neonates; 50 (31.4%) preterm and 109 term neonates, of whom 49 (30.8%) were treated with therapeutic hypothermia. Lidocaine clearance increased with postmenstrual age by 0.69%/day (95% confidence interval 0.54-0.84%). During therapeutic hypothermia (33.5°C), lidocaine clearance was reduced by 21.8% (7.26%/°C, 95% confidence interval 1.63-11.2%) compared to normothermia (36.5°C). Simulations demonstrated that the proposed dosing regimen leads to adequate average lidocaine plasma concentrations. Effectiveness and safety were assessed in 92 neonates. Overall effectiveness was 53.3% (49/92) and 56.5% (13/23) for neonates receiving the proposed dosing regimen. No cardiac toxicity was observed., Conclusion: Lidocaine pharmacokinetics was adequately described across the entire neonatal age range. With the proposed dosing regimen, lidocaine can provide effective and safe treatment for neonatal seizures., (© 2019 The Authors. British Journal of Clinical Pharmacology published by John Wiley & Sons Ltd on behalf of British Pharmacological Society.)

Objective: Morphine is a commonly used drug in encephalopathic neonates treated with therapeutic hypothermia after perinatal asphyxia. Pharmacokinetics and optimal dosing of morphine in this population are largely unknown. The objective of this study was to describe pharmacokinetics of morphine and its metabolites morphine-3-glucuronide and morphine-6-glucuronide in encephalopathic neonates treated with therapeutic hypothermia and to develop pharmacokinetics based dosing guidelines for this population., Study Design: Term and near-term encephalopathic neonates treated with therapeutic hypothermia and receiving morphine were included in two multicenter cohort studies between 2008-2010 (SHIVER) and 2010-2014 (PharmaCool). Data were collected during hypothermia and rewarming, including blood samples for quantification of morphine and its metabolites. Parental informed consent was obtained for all participants., Results: 244 patients (GA mean (sd) 39.8 (1.6) weeks, BW mean (sd) 3,428 (613) g, male 61.5%) were included. Morphine clearance was reduced under hypothermia (33.5°C) by 6.89%/°C (95% CI 5.37%/°C- 8.41%/°C, p<0.001) and metabolite clearance by 4.91%/°C (95% CI 3.53%/°C- 6.22%/°C, p<0.001) compared to normothermia (36.5°C). Simulations showed that a loading dose of 50 μg/kg followed by continuous infusion of 5 μg/kg/h resulted in morphine plasma concentrations in the desired range (between 10 and 40 μg/L) during hypothermia., Conclusions: Clearance of morphine and its metabolites in neonates is affected by therapeutic hypothermia. The regimen suggested by the simulations will be sufficient in the majority of patients. However, due to the large interpatient variability a higher dose might be necessary in individual patients to achieve the desired effect., Trial Registration: www.trialregister.nl NTR2529., Competing Interests: The authors have declared that no competing interests exist.

Background: Phenobarbital and midazolam are commonly used drugs in (near-)term neonates treated with therapeutic hypothermia for hypoxic-ischaemic encephalopathy, for sedation, and/or as anti-epileptic drug. Phenobarbital is an inducer of cytochrome P450 (CYP) 3A, while midazolam is a CYP3A substrate. Therefore, co-treatment with phenobarbital might impact midazolam clearance., Objectives: To assess pharmacokinetics and clinical anti-epileptic effectiveness of phenobarbital and midazolam in asphyxiated neonates and to develop dosing guidelines., Methods: Data were collected in the prospective multicentre PharmaCool study. In the present study, neonates treated with therapeutic hypothermia and receiving midazolam and/or phenobarbital were included. Plasma concentrations of phenobarbital and midazolam including its metabolites were determined in blood samples drawn on days 2-5 after birth. Pharmacokinetic analyses were performed using non-linear mixed effects modelling; clinical effectiveness was defined as no use of additional anti-epileptic drugs., Results: Data were available from 113 (phenobarbital) and 118 (midazolam) neonates; 68 were treated with both medications. Only clearance of 1-hydroxy midazolam was influenced by hypothermia. Phenobarbital co-administration increased midazolam clearance by a factor 2.3 (95% CI 1.9-2.9, p < 0.05). Anticonvulsant effectiveness was 65.5% for phenobarbital and 37.1% for add-on midazolam., Conclusions: Therapeutic hypothermia does not influence clearance of phenobarbital or midazolam in (near-)term neonates with hypoxic-ischaemic encephalopathy. A phenobarbital dose of 30 mg/kg is advised to reach therapeutic concentrations. Phenobarbital co-administration significantly increased midazolam clearance. Should phenobarbital be substituted by non-CYP3A inducers as first-line anticonvulsant, a 50% lower midazolam maintenance dose might be appropriate to avoid excessive exposure during the first days after birth., (© 2019 The Author(s) Published by S. Karger AG, Basel.)

The pharmacokinetic (PK) properties of intravenous (i.v.) benzylpenicillin in term neonates undergoing moderate hypothermia after perinatal asphyxia were evaluated, as they have been unknown until now. A system-specific modeling approach was applied, in which our recently developed covariate model describing developmental and temperature-induced changes in amoxicillin clearance (CL) in the same patient study population was incorporated into a population PK model of benzylpenicillin with a priori birthweight (BW)-based allometric scaling. Pediatric population covariate models describing the developmental changes in drug elimination may constitute system-specific information and may therefore be incorporated into PK models of drugs cleared through the same pathway. The performance of this system-specific model was compared to that of a reference model. Furthermore, Monte-Carlo simulations were performed to evaluate the optimal dose. The system-specific model performed as well as the reference model. Significant correlations were found between CL and postnatal age (PNA), gestational age (GA), body temperature (TEMP), urine output (UO; system-specific model), and multiorgan failure (reference model). For a typical patient with a GA of 40 weeks, BW of 3,000 g, PNA of 2 days (TEMP, 33.5°C), and normal UO (2 ml/kg/h), benzylpenicillin CL was 0.48 liter/h (interindividual variability [IIV] of 49%) and the volume of distribution of the central compartment was 0.62 liter/kg (IIV of 53%) in the system-specific model. Based on simulations, we advise a benzylpenicillin i.v. dose regimen of 75,000 IU/kg/day every 8 h (q8h), 150,000 IU/kg/day q8h, and 200,000 IU/kg/day q6h for patients with GAs of 36 to 37 weeks, 38 to 41 weeks, and ≥42 weeks, respectively. The system-specific model may be used for other drugs cleared through the same pathway accelerating model development., (Copyright © 2018 American Society for Microbiology.)