Pharmacokinetics in neonatal prescribing: evidence base, paradigms and the future

Population pharmacokinetic modelling of primaquine exposures in lactating women and breastfed infants

Current guidelines advise against primaquine treatment for breastfeeding mothers to avoid the potential for haemolysis in infants with G6PD deficiency. To predict the haemolytic risk, the amount of drug received from the breast milk and the resulting infant drug exposure need to be characterised. Here, we develop a pharmacokinetic model to describe the drug concentrations in breastfeeding women using venous, capillary, and breast milk data. A mother-to-infant model is developed to mimic the infant feeding pattern and used to predict their drug exposures. Primaquine and carboxyprimaquine exposures in infants are <1% of the exposure in mothers. Therefore, even in infants with the most severe G6PD deficiency variants, it is highly unlikely that standard doses of primaquine (0.25-1 mg base/kg once daily given to the mother for 1-14 days) would cause significant haemolysis. After the neonatal period, primaquine should not be restricted for breastfeeding women (Clinical Trials Registration: NCT01780753).

Parenteral nutrition emulsion inhibits CYP3A4 in an iPSC derived liver organoids testing platform

OBJECTIVES

Parenteral nutrition (PN) is used for patients of varying ages with intestinal failure to supplement calories. Premature newborns with low birth weight are at a high risk for developing PN associated liver disease (PNALD) including steatosis, cholestasis, and gallbladder sludge/stones. To optimize nutrition regimens, models are required to predict PNALD.

METHODS

We have exploited induced pluripotent stem cell derived liver organoids to provide a testing platform for PNALD. Liver organoids mimic the developing liver and contain the different hepatic cell types. The organoids have an early postnatal maturity making them a suitable model for premature newborns. To mimic PN treatment we used medium supplemented with either clinoleic (80% olive oil/20% soybean oil) or intralipid (100% soybean oil) for 7 days.

RESULTS

Homogenous HNF4a staining was found in all organoids and PN treatments caused accumulation of lipids in hepatocytes. Organoids exhibited a dose dependent decrease in CYP3A4 activity and expression of hepatocyte functional genes. The lipid emulsions did not affect overall organoid viability and glucose levels had no contributory effect to the observed results.

CONCLUSIONS

Liver organoids could be utilized as a potential screening platform for the development of new, less hepatotoxic PN solutions. Both lipid treatments caused hepatic lipid accumulation, a significant decrease in CYP3A4 activity and a decrease in the RNA levels of both CYP3A4 and CYP1A2 in a dose dependent manner. The presence of high glucose had no additive effect, while Clinoleic at high dose, caused significant upregulation of interleukin 6 and TLR4 expression.

Tripled likelihood: polypharmacy increases the occurrence of drug therapy problems in hospitalized pediatric patients

Background

A drug therapy problem (DTP) is any undesirable event experienced by a patient that accompanies drug therapy, prevents the patient from achieving their desired therapeutic goals, and requires expert judgment to resolve. Pediatric populations are at a higher risk of DTP than adults due to their immature organ systems, including the liver and kidneys, which play crucial roles in drug metabolism and excretion. Most previous studies have focused on only one element of DTP. Therefore, by considering all elements of DTP, we aimed to assess the prevalence of DTP and associated factors among pediatric patients admitted to the Wolaita Sodo University Comprehensive Specialized Hospital.

Methods

An institution-based cross-sectional study was conducted among pediatric patients admitted to Wolaita Sodo University Comprehensive Specialized Hospital from 8 July 2020, to 7 July 2021. A simple random sampling technique was employed to select study participants. Cipolle's and Strand's classification method of drug therapy problems was used to identify and categorize DTP. Data were obtained by reviewing the patient's medical records using a data abstraction checklist, entered into Epi data version 4.6, and exported to SPSS version 25 for analysis. Binary logistic regression analysis was performed to identify independent predictors of DTP.

Results

Medical records of 369 pediatric patients were reviewed, and the overall prevalence of DTP was 60.2% (95% CI:55.2%, 65.2%) with a total of 281 identified DTPs. Among them, 164 (74.2%) had only one DTP. Need additional drug therapy was the most common (140 [49.8%]) DTP identified. The number of disease conditions (AOR = 2.13, 95% CI:1.16, 3.92), polypharmacy (AOR = 3.01, 95% CI:1.70, 5.32), and duration of hospital stay (AOR = 1.80, 95% CI:1.04, 3.10) were independent predictors of DTP among admitted pediatric patients.

Conclusion

The prevalence of DTP in pediatric patients in the current setting was high. The number of disease conditions, polypharmacy, and duration of hospital stay were independent predictors of DTP. Enhancements to pharmaceutical care services, optimized dosage practices, improved deprescribing by clinicians, and efficient, comprehensive diagnostic procedures have the potential to significantly reduce specific drug therapy problems in hospitalized pediatrics.

Medicines management in children and young people: pharmacokinetics, drug calculations and off-label drug use

Medicines management in children and young people presents specific challenges because children differ from adults in their response to medicines. The way in which medicines work inside the human body, or pharmacokinetics, varies according to age and stage of development. Accurate drug calculations for a child rely on the careful consideration of a series of factors, such as weight and height, pharmacokinetics and drug characteristics. This article focuses on three fundamental aspects: pharmacokinetics, drug calculations, and unlicensed and off-label drug use.

Pharmacological Management of Cardiac Arrhythmias in the Fetal and Neonatal Periods: A Scientific Statement From the American Heart Association: Endorsed by the Pediatric & Congenital Electrophysiology Society (PACES)

Disorders of the cardiac rhythm may occur in both the fetus and neonate. Because of the immature myocardium, the hemodynamic consequences of either bradyarrhythmias or tachyarrhythmias may be far more significant than in mature physiological states. Treatment options are limited in the fetus and neonate because of limited vascular access, patient size, and the significant risk/benefit ratio of any intervention. In addition, exposure of the fetus or neonate to either persistent arrhythmias or antiarrhythmic medications may have yet-to-be-determined long-term developmental consequences. This scientific statement discusses the mechanism of arrhythmias, pharmacological treatment options, and distinct aspects of pharmacokinetics for the fetus and neonate. From the available current data, subjects of apparent consistency/consensus are presented, as well as future directions for research in terms of aspects of care for which evidence has not been established.

Population Pharmacokinetics of Caffeine in Neonates with Congenital Heart Disease and Associations with Acute Kidney Injury

Cardiac surgery-associated acute kidney injury (CS-AKI) occurs in approximately 65% of neonates undergoing cardiac surgery on cardiopulmonary bypass and contributes to morbidity and mortality. Caffeine may reduce CS-AKI by counteracting adenosine receptor upregulation after bypass, but pharmacokinetics (PK) in this population are unknown. The goal of our analysis is to address knowledge gaps in age-, disease-, and bypass-related effects on caffeine disposition and explore preliminary associations between caffeine exposure and CS-AKI using population PK modeling techniques and an opportunistic, electronic health record-integrated trial design. We prospectively enrolled neonates receiving preoperative caffeine per standard of care and collected PK samples. We retrospectively identified neonates without caffeine exposure undergoing surgery on bypass as a control cohort. We followed US Food and Drug Administration guidance for population PK model development using NONMEM. Effects of clinical covariates on PK parameters were evaluated. We simulated perioperative exposures and used multivariable logistic regression to evaluate the association between caffeine exposure and CS-AKI. Twenty-seven neonates were included in model development. A 1-compartment model with bypass time as a covariate on clearance and volume of distribution best fit the data. Twenty-three neonates with caffeine exposure and 109 controls were included in the exposure-response analysis. Over half of neonates developed CS-AKI. On multivariable analysis, there were no significant differences between CS-AKI with and without caffeine exposure. Neonates with single-ventricle heart disease without CS-AKI had consistently higher simulated caffeine exposures. Our results highlight areas for further study to better understand disease- and bypass-specific effects on drug disposition and identify populations where caffeine may be beneficial.

Establishment of a children's Drugs and Therapeutics Committee to ensure evidence-based and cost-effective medical treatment for children

The prevalence of undocumented medical treatments among children is a significant issue, as well as many EU countries lack access to newly developed children-friendly medicines. Consequently, there is a pressing need for supplementary resources that can facilitate informed decision-making regarding children's medication. We therefore aim to describe the process of establishing a children's Drug and Therapeutics Committee (cDTC), as well as the preparing and implementation of recommendations for children in the capital region of Denmark. Following the guidelines outlined by the World Health Organization, we established a cDTC, and recommendations for paediatric medication practice were constructed from assessments of medication use patterns among children in the capital region between 2019 and 2021. The recommendations were meticulously crafted based on evaluation of the current marketing authorization landscape and existing best available evidence. In 2019, the capital region established the first cDTC supported by expert councils and an editorial board. A total of 2429 purchase item numbers covering 1 222 846 defined daily doses and 592 088 purchased packages covering 10 200 000 defined daily doses were identified in the secondary and primary sectors, respectively. Three comprehensive lists covering recommendations for newborns and children were published between 2021 and 2020 totaling 331 recommended pharmaceutical products. The recommendations primarily intended for use in the secondary healthcare sector were implemented through the revision of 38 paediatric- and six neonatal product ranges throughout capital region. In conclusion, recommendation lists for children governed by a cDTC provide a rational auxiliary tool that can be immediately implemented in the clinic.

The Dangers of Acetaminophen for Neurodevelopment Outweigh Scant Evidence for Long-Term Benefits

Based on available data that include approximately 20 lines of evidence from studies in laboratory animal models, observations in humans, correlations in time, and pharmacological/toxicological considerations, it has been concluded without reasonable doubt and with no evidence to the contrary that exposure of susceptible babies and children to acetaminophen (paracetamol) induces many, if not most, cases of autism spectrum disorder (ASD). However, the relative number of cases of ASD that might be induced by acetaminophen has not yet been estimated. Here, we examine a variety of evidence, including the acetaminophen-induced reduction of social awareness in adults, the prevalence of ASD through time, and crude estimates of the relative number of ASD cases induced by acetaminophen during various periods of neurodevelopment. We conclude that the very early postpartum period poses the greatest risk for acetaminophen-induced ASD, and that nearly ubiquitous use of acetaminophen during early development could conceivably be responsible for the induction in the vast majority, perhaps 90% or more, of all cases of ASD. Despite over a decade of accumulating evidence that acetaminophen is harmful for neurodevelopment, numerous studies demonstrate that acetaminophen is frequently administered to children in excess of currently approved amounts and under conditions in which it provides no benefit. Further, studies have failed to demonstrate long-term benefits of acetaminophen for the pediatric population, leaving no valid rationale for continued use of the drug in that population given its risks to neurodevelopment.

Predicting Volume of Distribution in Neonates: Performance of Physiologically Based Pharmacokinetic Modelling

The volume of distribution at steady state (Vss) in neonates is still often estimated through isometric scaling from adult values, disregarding developmental changes beyond body weight. This study aimed to compare the accuracy of two physiologically based pharmacokinetic (PBPK) Vss prediction methods in neonates (Poulin & Theil with Berezhkovskiy correction (P&T+) and Rodgers & Rowland (R&R)) with isometrical scaling. PBPK models were developed for 24 drugs using in-vitro and in-silico data. Simulations were done in Simcyp (V22) using predefined populations. Clinical data from 86 studies in neonates (including preterms) were used for comparison, and accuracy was assessed using (absolute) average fold errors ((A)AFEs). Isometric scaling resulted in underestimated Vss values in neonates (AFE: 0.61), and both PBPK methods reduced the magnitude of underprediction (AFE: 0.82-0.83). The P&T+ method demonstrated superior overall accuracy compared to isometric scaling (AAFE of 1.68 and 1.77, respectively), while the R&R method exhibited lower overall accuracy (AAFE: 2.03). Drug characteristics (LogP and ionization type) and inclusion of preterm neonates did not significantly impact the magnitude of error associated with isometric scaling or PBPK modeling. These results highlight both the limitations and the applicability of PBPK methods for the prediction of Vss in the absence of clinical data.

Plasma and Cerebrospinal Fluid Concentrations of Micafungin Administered at High Doses in Critically Ill Infants with Systemic Candidiasis: A Pooled Analysis of Two Studies

Background: Neonates may require higher doses of micafungin than adults to reach the therapeutic effect for increased plasma clearance. Only poor and inconclusive data are available still now to support this hypothesis, especially with regard to central nervous system micafungin concentrations. To assess the pharmacokinetics of increased doses (8 to 15 mg/kg/day) of micafungin in preterm and term neonates with invasive candidiasis and to complete previously presented results, we analyzed the pharmacokinetic data on a total of 53 newborns treated with micafungin, whereby 3 of them had Candida meningitis and hydrocephalus. Methods: Fifty-three neonates with systemic candidiasis, three of them with meningitis, were treated for at least 14 days with intravenous micafungin (Mycamine^®) at a dosage ranging from 8 to 15 mg/kg/day. Plasma and cerebrospinal fluid (CSF) concentrations of micafungin were measured before the drug administration and at 1, 2, and 8 h after the end of the infusion using high-performance liquid chromatography (HPLC). Systemic exposure was assessed according to AUC_0-24, plasma clearance (CL), and half-life measured in 52/53 patients, divided by chronological age. Results and conclusions: The mean micafungin clearance is higher in neonates than in older infants (0.036 L/h/kg before 28 days of life versus 0.028 L/h/kg after 120 days). The drug half-life is shorter in neonates than in older patients (13.5 h before 28 days of life versus 14.4 h after 120 days). With doses ranging between 8 and 15 mg/kg/day, micafungin crosses the blood-brain barrier reaching therapeutic levels in CSF.

Massive presence of off-label medicines in Danish neonatal departments: A nationwide survey using national hospital purchase data

There is currently insufficient knowledge of gestational age dependent medicine disposition in neonates. Accordingly, the use of off-label medication, i.e., use of medicines outside its approved marketing authorization, is high in the neonatal departments. By using data from the Danish National Pharmaceutical Hospital Purchase Database, we identified the most commonly occurring medications and calculated the on/off-label ratios for premature and term neonates. Data was extracted on ATC level 5 and based on defined daily doses as per WHO. Data covered the 4 high-level NICUs and 10 of 13 of the intermediate/standard level Danish neonatal departments. Of the identified medication, 87% and 70% did not have approved marketing authorization for use in premature and full-term neonates, respectively. Furthermore, one-fifth of the top 100 medicines did not have a (Danish) marketing license. Overall, off-label medication was widespread covering virtually all ATC groups and no ATC group had an off-label level lower than 50% (range 50%-100%). Finally, in 21% of medications, additives from 8 different chemical groups with potential deleterious effects for neonates were identified. In conclusion, off-label medication in the Danish neonatal departments is widespread. The pharmaceutical industry is unlikely to solve this problem, and we may for a very long time be occasionally forced to use off-label medication. Practical solution must therefore come from multidisciplinary clinical and academic collaboration. Use of formulation list as guidance for prescriptions and NICU-friendly galenic formulations may mitigate the problem temporarily while waiting for definitive studies.

Caffeine dosing in premature neonates: impact of birth weight on a pharmacokinetic simulation study

BACKGROUND

The optimal caffeine dosing in extremely premature neonates remains elusive. This study aimed to evaluate the impact of birth weight on caffeine pharmacokinetics and various dosing regimens.

METHODS

In this pharmacokinetic simulation study, we generated the body weights (0-49 days of postnatal age [PNA]) of neonates <28 weeks gestational age with different birth weights (550, 750, and 1050 g). Their pharmacokinetic parameters were determined based on published pharmacokinetic models. Then, we simulated and compared the caffeine base concentration-time profiles of standard versus off-label caffeine citrate dose regimens.

RESULTS

The half-life decreased and the weight-adjusted clearance increased more significantly in neonates with lower birth weights, resulting in lower caffeine plasma concentrations. The neonate with the lowest birth weight did not achieve a threshold trough concentration of 15 mg/L after receiving the standard dose (5 mg/kg/day), while the higher-birth-weights (≥750 g) had trough concentrations below the threshold around the second week of life. Higher caffeine doses (10 mg/kg/day) resulted in peak concentrations of <36 mg/L by 10-14 days of PNA while maintaining trough concentrations above 15 mg/L throughout the 49 days PNA.

CONCLUSION

Higher-than-standard caffeine dosing may be needed for extremely premature neonates, especially for those with lower birth weights.

IMPACT

Extremely premature neonates with a lower birth weight may require a higher weight-based caffeine dosing due to their higher weight-adjusted clearance and shorter half-lives. Not only do these extremely premature neonates have a higher risk of developing bronchopulmonary dysplasia due to their structurally underdeveloped lungs, but the low birth weight-related underdosing may further contribute to the reduced caffeine effectiveness. Higher-than-standard caffeine citrate dosing (e.g., 10 mg/kg/day maintenance dose) may be needed to further prevent bronchopulmonary dysplasia.

Gene expression profiling after exposure to a chemical carcinogen, Pentabrominated Diphenyl Ether, at different life stages

Exposure to environmental hazards occurs at different stages of our lifetime-infant, child, adult. This study integrates recently published toxicogenomics data to examine how exposure to a known rat chemical carcinogen (pentabrominated diphenyl ether (PBDE)) upregulated liver transcriptomic changes at different life cycle stages (PND 4, PND 22, adult). We found that at all three life cycle stages PBDE exposure induced hepatocellular transcriptomic changes in disease pathways including cancer, metabolic, membrane function, and Nrf2 antioxidant pathways, pathways all characteristics of chemical carcinogens. In addition, in the adult rat after a 5-day exposure to the chemical carcinogen, there was upregulation of members of the Ras oncogenic pathway, a specific pathway found to be activated in the PBDE-induced tumors in rats in a previous hazard identification cancer study. The findings of liver transcript changes characteristic of carcinogenic activity after early life exposures and after short-term adult exposures provides data to support the use of transcriptomic data to predict the apical cancer endpoints in model studies. Using data from gene expression profiling studies after neonatal, young, or adult short-term chemical exposure helps to meet the 21st century toxicology goal of developing study designs to reduce, refine, and replace the use of traditional 2-year rodent cancer studies to provide hazard identification information. The studies reported here find that key transcripts associated with carcinogenesis were elevated in neonate (PND 4), young (PND 22) and adult animals after short-term exposure to PBDE, a known experimental chemical carcinogen in model systems.

Ontogeny of CYP3A and UGT activity in preterm piglets: a translational model for drug metabolism in preterm newborns

Despite considerable progress in understanding drug metabolism in the human pediatric population, data remains scarce in preterm neonates. Improving our knowledge of the ADME properties in this vulnerable age group is of utmost importance to avoid suboptimal dosing, which may lead to adverse drug reactions. The juvenile (mini)pig is a representative model for hepatic drug metabolism in human neonates and infants, especially phase I reactions. However, the effect of prematurity on the onset of hepatic phase I and phase II enzyme activity has yet to be investigated in this animal model. Therefore, the aim of this study was to assess the ontogeny of CYP3A and UGT enzyme activity in the liver of preterm (gestational day 105-107) and term-born (gestational day 115-117) domestic piglets. In addition, the ontogeny pattern between the preterm and term group was compared to examine whether postconceptional or postnatal age affects the onset of enzyme activity. The following age groups were included: preterm postnatal day (PND) 0 (n = 10), PND 5 (n = 10), PND 11 (n = 8), PND 26 (n = 10) and term PND 0 (n = 10), PND 5 (n = 10), PND 11 (n = 8), PND 19 (n = 18) and PND 26 (n = 10). Liver microsomes were extracted, and the metabolism of CYP3A and UGT-specific substrates assessed enzyme activity. Preterm CYP3A activity was only detectable at PND 26, whereas term CYP3A activity showed a gradual postnatal increase from PND 11 onwards. UGT activity gradually increased between PND 0 and PND 26 in preterm and term-born piglets, albeit, being systematically lower in the preterm group. Thus, postconceptional age is suggested as the main driver affecting porcine CYP3A and UGT enzyme ontogeny. These data are a valuable step forward in the characterization of the preterm piglet as a translational model for hepatic drug metabolism in the preterm human neonate.

Infant Exposure to Armodafinil Through Human Milk Following Maternal Use of Modafinil

INTRODUCTION

Narcolepsy, a condition adversely affecting psychological, social, and cognitive function, is more prevalent in females of childbearing age than the general population. Modafinil and armodafinil are central nervous system stimulants approved for treatment of narcolepsy. Infant exposure to these agents through human milk has not been investigated. Poor quality medication safety information during lactation is associated with early cessation of breastfeeding and suboptimal healthcare for the breastfeeding family.

MAIN ISSUE

In this case study, we measured the concentration of armodafinil (the most active form of modafinil) in human milk and infant plasma to quantify infant exposure.

MANAGEMENT

The participant was a 30-year-old primipara with narcolepsy, taking modafinil (300 mg morning, 100 mg noon) while breastfeeding her 6-week-old infant despite the paucity of safety information. Armodafinil concentrations were measured in eight serial human milk samples collected over a 26-hr period and in single maternal and infant plasma samples using ultra performance liquid chromatography - tandem mass spectrometry. The average concentration of armodafinil in human milk was 1.96 mg/L; the relative infant dose was 4.85%; the theoretical infant dose was 0.294 mg/kg/day. Maternal and infant plasma concentrations of armodafinil were 12.02 mg/L and 0.19 mg/L, respectively. The participant continued to exclusively breastfeed the infant, who had normal growth and development.

CONCLUSION

Based on these findings, relatively small amounts of armodafinil pass into human milk, with consequent limited infant exposure. Consideration can be given to the use of modafinil or armodafinil during breastfeeding, provided the infant is monitored. Further studies are needed to confirm these findings.

Pediatric Clinical Research Networks: Role in Accelerating Development of Therapeutics in Children

Background

Recent decades have seen many advances in policy and legislation that support the development of drugs used by neonates, infants, children, and young people. This review summarizes the characteristics and performance of networks capable of conducting studies needed to meet regulatory requirements and make advances in pediatric drug development.

Methods

Description of network goals and capabilities by network leaders.

Results

In the United States, Europe, Japan, and Canada, clinical research networks have been organized to meet the needs of biopharmaceutical and academic sponsors for timely access to high-quality sites, as well as to provide advice about drug development with regard to strategic and operational feasibility. Each network addresses the specificities of its context while working toward shared principles including standards and timelines; alignment of goals and processes, while not disturbing arrangements for conducting trials that work well; wide geographic coverage; all age groups and pediatric conditions; sources of funding; sites that compete on performance; performance monitoring for benchmarking, and opportunities to optimize the allocation of resources; and education and training for network members. Facilitation in interactions among these networks is based on a single point-of-contact for each; similar approaches to strategic and operational feasibility assessment, and site selection; and collaborative approaches to education and training.

Conclusion

Within five years, clinical research networks will support the needs of biopharmaceutical and publicly funded pediatric drug development through locally appropriate and globally interoperable approaches.

Use of Antibiotics in Preterm Newborns

Due to complex maturational and physiological changes that characterize neonates and affect their response to pharmacological treatments, neonatal pharmacology is different from children and adults and deserves particular attention. Although preterms are usually considered part of the neonatal population, they have physiological and pharmacological hallmarks different from full-terms and, therefore, need specific considerations. Antibiotics are widely used among preterms. In fact, during their stay in neonatal intensive care units (NICUs), invasive procedures, including central catheters for parental nutrition and ventilators for respiratory support, are often sources of microbes and require antimicrobial treatments. Unfortunately, the majority of drugs administered to neonates are off-label due to the lack of clinical studies conducted on this special population. In fact, physiological and ethical concerns represent a huge limit in performing pharmacokinetic (PK) studies on these subjects, since they limit the number and volume of blood sampling. Therapeutic drug monitoring (TDM) is a useful tool that allows dose adjustments aiming to fit plasma concentrations within the therapeutic range and to reach specific drug target attainment. In this review of the last ten years’ literature, we performed Pubmed research aiming to summarize the PK aspects for the most used antibiotics in preterms.

Pharmacokinetics of Cannabis and Its Derivatives in Animals and Humans During Pregnancy and Breastfeeding

Cannabis is one of the most widely used illicit drugs during pregnancy and lactation. With the recent legalization of cannabis in many countries, health professionals are increasingly exposed to pregnant and breastfeeding women who are consuming cannabis on a regular basis as a solution for depression, anxiety, nausea, and pain. Cannabis consumption during pregnancy can induce negative birth outcomes such as reduced birth weight and increased risk of prematurity and admission to the neonatal intensive care unit. Yet, limited information is available regarding the pharmacokinetics of cannabis in the fetus and newborn exposed during pregnancy and lactation. Indeed, the official recommendations regarding the use of cannabis during these two critical development periods lack robust pharmacokinetics data and make it difficult for health professionals to guide their patients. Many clinical studies are currently evaluating the effects of cannabis on the brain development and base their groups mostly on questionnaires. These studies should be associated with pharmacokinetics studies to assess correlations between the infant brain development and the exposure to cannabis during pregnancy and breastfeeding. Our project aims to review the available data on the pharmacokinetics of cannabinoids in adults, neonates, and animals. If the available literature is abundant in adult humans and animals, there is still a lack of published data on the exposure of pregnant and lactating women and neonates. However, some of the published information causes concerns on the exposure and the potential effects of cannabis on fetuses and neonates. The safety of cannabis use for non-medical purpose during pregnancy and breastfeeding needs to be further characterized with proper pharmacokinetic studies in humans feasible in regions where cannabis has been legalized. Given the available data, significant transfer occurs to the fetus and the breastfed newborn with a theoretical risk of accumulation of products known to be biologically active.

Ways to Improve Insights into Clindamycin Pharmacology and Pharmacokinetics Tailored to Practice

Given the increase in bacterial resistance and the decrease in the development of new antibiotics, the appropriate use of old antimicrobials has become even more compulsory. Clindamycin is a lincosamide antibiotic approved for adults and children as a drug of choice for systemic treatment of staphylococcal, streptococcal, and gram-positive anaerobic bacterial infections. Because of its profile and high bioavailability, it is commonly used as part of an oral multimodal alternative for prolonged parenteral antibiotic regimens, e.g., to treat bone and joint or prosthesis-related infections. Clindamycin is also frequently used for (surgical) prophylaxis in the event of beta-lactam allergy. Special populations (pediatrics, pregnant women) have altered cytochrome P450 (CYP)3A4 activity. As clindamycin is metabolized by the CYP3A4/5 enzymes to bioactive N-demethyl and sulfoxide metabolites, knowledge of the potential relevance of the drug’s metabolites and disposition in special populations is of interest. Furthermore, drug–drug interactions derived from CYP3A4 inducers and inhibitors, and the data on the impact of the disease state on the CYP system, are still limited. This narrative review provides a detailed survey of the currently available literature on pharmacology and pharmacokinetics and identifies knowledge gaps (special patient population, drug–drug, and drug–disease interactions) to describe a research strategy for precision medicine.

The Blind Spot of Pharmacology: A Scoping Review of Drug Metabolism in Prematurely Born Children

The limit for possible survival after extremely preterm birth has steadily improved and consequently, more premature neonates with increasingly lower gestational age at birth now require care. This specialized care often include intensive pharmacological treatment, yet there is currently insufficient knowledge of gestational age dependent differences in drug metabolism. This potentially puts the preterm neonates at risk of receiving sub-optimal drug doses with a subsequent increased risk of adverse or insufficient drug effects, and often pediatricians are forced to prescribe medication as off-label or even off-science. In this review, we present some of the particularities of drug disposition and metabolism in preterm neonates. We highlight the challenges in pharmacometrics studies on hepatic drug metabolism in preterm and particularly extremely (less than 28 weeks of gestation) preterm neonates by conducting a scoping review of published literature. We find that >40% of included studies failed to report a clear distinction between term and preterm children in the presentation of results making direct interpretation for preterm neonates difficult. We present summarized findings of pharmacokinetic studies done on the major CYP sub-systems, but formal meta analyses were not possible due the overall heterogeneous approaches to measuring the phase I and II pathways metabolism in preterm neonates, often with use of opportunistic sampling. We find this to be a testament to the practical and ethical challenges in measuring pharmacokinetic activity in preterm neonates. The future calls for optimized designs in pharmacometrics studies, including PK/PD modeling-methods and other sample reducing techniques. Future studies should also preferably be a collaboration between neonatologists and clinical pharmacologists.

Medication Use in the Neonatal Intensive Care Unit and Changes from 2010 to 2018

OBJECTIVE

To provide up-to-date medication prescribing patterns in US neonatal intensive care units (NICUs) and to examine trends in prescribing patterns over time.

STUDY DESIGN

We performed a cohort study of 799 016 infants treated in NICUs managed by the Pediatrix Medical Group from 2010 to 2018. We used 3 different methods to report counts of medication: exposure, courses, and days of use. We defined the change in frequency of medication administration by absolute change and relative change. We examined the Food and Drug Administration (FDA) package insert for each medication to determine whether a medication was labeled for use in infants and used PubMed to search for pharmacokinetics (PK) studies.

RESULTS

The most frequently prescribed medications included ampicillin, gentamicin, caffeine citrate, poractant alfa, morphine, vancomycin, furosemide, fentanyl, midazolam, and acetaminophen. Of the top 50 medications used in infants with extremely low birth weight, only 20 (40%) are FDA-labeled for use in infants; of the 30 that are not labeled for use in infants, 13 (43%) had at least 2 published PK studies. The medications with the greatest relative increase in use from 2010 to 2018 included dexmedetomidine, clonidine, rocuronium, levetiracetam, atropine, and diazoxide. The medications with the greatest relative decrease in use included tromethamine acetate, pancuronium, chloral hydrate, imipenem + cilastatin, and amikacin.

CONCLUSION

Trends of medication use in the NICU change substantially over time. It is imperative to identify changes in medication use in the NICU to better inform further prospective studies.

First-in-human pharmacokinetics of tamoxifen and its metabolites in the milk of a lactating mother: a case study

BackgroundBreast cancer represents the most frequent neoplasm diagnosed in women of childbearing age. When the tumour is oestrogen receptor-positive, tamoxifen is among the recommended endocrine treatments. Lactating women are advised not to breastfeed while receiving tamoxifen. However, information about tamoxifen transfer into breast milk is lacking.MethodsWe measured the concentration of tamoxifen and its metabolites by liquid chromatography-tandem mass spectrometry in the milk of a nursing mother that was treated for pregnancy-associated breast cancer diagnosed a few months after delivery. She was advised not to breastfeed her child and she collected milk samples for 23 days while the baby was fed with formula.ResultsTamoxifen concentrations in milk increased reaching a maximum of 214 nM. The two active metabolitesZ-4-hydroxy-tamoxifen and Z-endoxifen, could not be quantified in milk the first days after tamoxifen intake, but increased over time and reached clinically significant levels after day 18.ConclusionThis study demonstrates for the first time in human that tamoxifen and its metabolites transfer into milk. Since tamoxifen has a complete oral bioavailability, a long half-life (>7 days) and may interfere with the normal development of the infant, mothers should not breastfeed during tamoxifen treatment.

Caffeine disrupts ataxia telangiectasia mutated gene-related pathways and exacerbates acetaminophen toxicity in human fetal immortalized hepatocytes

Preterm infants are at greater risk for adverse drug effects due to hepatic immaturity. Multiple interventions during intensive care increases potential for drug interactions. In this setting, high-dose caffeine used for apnea in premature infants may increase acetaminophen toxicity by inhibiting ataxia telangiectasia mutated (ATM) gene activity during DNA damage response. To define caffeine and acetaminophen interaction, we modeled infantile prematurity in late-gestation fetal stage through human immortalized hepatocytes and liver organoids. The acute toxicity studies included assays for cell viability, mitochondrial dysfunction and ATM pathway-related DNA damage. Fetal cells expressed hepatobiliary properties, albeit with lower metabolic, synthetic and antioxidant functions than more mature hepatocytes. Acetaminophen in IC50 amount of 7.5 millimolar caused significant oxidative stress, mitochondrial membrane potential impairments, and DNA breaks requiring ATM-dependent repair. Caffeine markedly exacerbated acetaminophen toxicity by suppressing ATM activity in otherwise nontoxic 2.5 millimolar amount. Similarly, the specific ATM kinase antagonist, KU-60019, reproduced this deleterious interaction in 5 micromolar amount. Replicative stress from combined acetaminophen and caffeine toxicity depleted cells undergoing DNA synthesis in S phase and activated checkpoints for G0/G1 or G2/M restrictions. Synergistic caffeine and acetaminophen toxicity in liver organoids indicated these consequences should apply in vivo. The antioxidant, N-acetylcysteine, decreased oxidative damage, mitochondrial dysfunction and ATM pathway disruption to mitigate caffeine and acetaminophen toxicity. We concluded that hepatic DNA damage, mitochondrial impairment and growth-arrest after combined caffeine and acetaminophen toxicity will be harmful for premature infants. Whether caffeine and acetaminophen toxicity may alter outcomes in subsequently encountered hepatic disease needs consideration.

Benzylpenicillin Serum Concentrations in Neonates With Group B Streptococci Sepsis or Meningitis: A Descriptive Cohort Study

BACKGROUND

Adequate dosage recommendations are imperative for successful treatment of invasive infections. We evaluated the occurrence of sub- and supratherapeutic serum and cerebrospinal fluid (CSF) concentrations of benzylpenicillin (BPEN) in neonates treated for a severe group B streptococci (GBS) sepsis and/or meningitis as well as discrepancies in dosing recommendations provided by pediatric reference sources.

METHODS

Retrospective analysis of (pre)term infants treated with BPEN undergoing therapeutic drug monitoring (TDM) between May 2015 and May 2019. Outcomes included numbers of sub- and supratherapeutic concentrations, and dose adjustments, clinical evolution, and dosing recommendations from six pediatric reference sources.

RESULTS

A total of 21 TDM samples from 8 neonates were evaluated. Among serum concentrations, 9/21 (43%) were below and 8/21 (38%) above the pre-specified therapeutic target range of 10-20 mg/L. Only 1 patient had BPEN determined in CSF whose concentration was below the lower limit of quantification. TDM identified a need for dose modification in 10/21 (48%) instances. Three of eight patients exhibited complete resolution of clinical, laboratory and radiologic signs of infection. Substantial variation in dosing recommendations (50,000-400,000 IE/kg/d) was present between reference sources.

CONCLUSIONS

Our data reveal that under current dosage recommendations, the predefined target serum or CSF concentrations of BPEN are not achieved in all children. In case of clinical failure, serum and/or CSF BPEN concentrations should be determined. Given the wide variation in concentrations and subsequent dose requirements, further exploration of the clinical and pharmacologic characteristics of BPEN in (pre)term neonates is essential to optimize therapeutic efficacy.

Inhibition of CYP3A7 DHEA-S Oxidation by Lopinavir and Ritonavir: An Alternative Mechanism for Adrenal Impairment in HIV Antiretroviral-Treated Neonates

Prophylactic antiretroviral therapy (ART) in HIV infected pregnant mothers and their newborns can dramatically reduce mother-to-child viral transmission and seroconversion in the neonate. The ritonavir-boosted lopinavir regimen, known as Kaletra, has been associated with premature birth and transient adrenal insufficiency in newborns, accompanied by increases in plasma dehydroepiandrosterone 3-sulfate (DHEA-S). In the fetus and neonates, cytochrome P450 CYP3A7 is responsible for the metabolism of DHEA-S into 16α-hydroxy DHEA-S, which plays a critical role in growth and development. In order to determine if CYP3A7 inhibition could lead to the adverse outcomes associated with Kaletra therapy, we conducted in vitro metabolic studies to determine the extent and mechanism of CYP3A7 inhibition by both ritonavir and lopinavir and the relative intrinsic clearance of lopinavir with and without ritonavir in both neonatal and adult human liver microsomes (HLMs). We identified ritonavir as a potent inhibitor of CYP3A7 oxidation of DHEA-S (IC₅₀ = 0.0514 μM), while lopinavir is a much weaker inhibitor (IC₅₀ = 5.88 μM). Furthermore, ritonavir is a time-dependent inhibitor of CYP3A7 with a K_I of 0.392 μM and a k_inact of 0.119 min^–1, illustrating the potential for CYP3A mediated drug–drug interactions with Kaletra. The clearance rate of lopinavir in neonatal HLMs was much slower and comparable to the rate observed in adult HLMs in the presence of ritonavir, suggesting that the addition of ritonavir in the cocktail therapy may not be necessary to maintain effective concentrations of lopinavir in neonates. Our results suggest that several of the observed adverse outcomes of Kaletra therapy may be due to the direct inhibition of CYP3A7 by ritonavir and that the necessity for the inclusion of this drug in the therapy may be obviated by the lower rate of lopinavir clearance in the neonatal liver. These results may lead to a reconsideration of the use of ritonavir in neonatal antiretroviral therapy.

Randomized Trial on Echocardiography-Guided Ductus Arteriosus Treatment to Reduce Necrotizing Enterocolitis

OBJECTIVE

Patent ductus arteriosus (PDA) approach remains controversial. We aim to evaluate whether echocardiography-guided (EchoG) PDA closure (to reduce drug exposure) and 24-h continuous ibuprofen infusion (24 h-IB) (to reduce peak concentration), compared with EchoG PDA closure plus conventional bolus (bolus-IB), reduces severe bowel adverse event rate in preterm infants with hemodynamically significant (hs) PDA.

STUDY DESIGN

The study design is a multicenter, blinded, randomized controlled trial. Infants with <28 weeks of gestation underwent routine echocardiographic assessment (18-72 h of birth); infants with 28-33 weeks were screened only in cases where PDA was clinically suspected. HsPDA was considered if ductal diameter >1.5 mm and indicators of pulmonary overflow, systemic hypoperfusion, or both were present. Pharmacodynamic effect of CYP450 genotypes was also analyzed.

RESULTS

One hundred forty-six infants [median gestational age 26 (25-28) weeks; median birth weight 881 (704-1,100) g] were randomized to 24 h-IB (n = 70) or bolus-IB (n = 76) study group at 86 (58-140) h from birth. Groups were comparable regarding perinatal and neonatal clinical data, but higher prevalence of male sex in the bolus-IB group was found. Neither severe bowel adverse event rate [10% (24 h-IB) and 2.6% (bolus-IB), p = 0.1] nor ductal closure rate was different between the study groups. Postnatal age and peripheral SaO2 at treatment start and pulmonary hemorrhage were associated with severe bowel events, independent of treatment group allocation. CYP2C8 genetic polymorphisms were associated with ibuprofen efficacy (p = 0.03).

CONCLUSIONS

Ibuprofen intravenous continuous infusion compared with bolus infusion in preterm infants with hsPDA shows similar rates of success and does not reduce the prevalence of severe bowel events.

Pharmacokinetics of a sulfadiazine and trimethoprim suspension in neonatal foals

There is limited investigation of neonatal foal pharmacokinetic parameters for the antimicrobial combination of sulfadiazine (SDZ) and trimethoprim (TMP). Neonatal pharmacokinetic investigation of the sulfadiazine-trimethoprim combination is required to ensure safe and effective utilization in this population. The purpose of this study was to determine the pharmacokinetics of sulfadiazine-trimethoprim in five healthy neonatal foals with oral administration at 24 mg/kg every 12 hr (hrs) for 10 days. Blood samples were collected at serial time points at approximately 72 hr of age (steady-state) and at days 5 and 10 to monitor the influence of age within the neonatal period. Pharmacokinetic parameters were determined using a one-compartment model analysis, and mean ± SD was calculated. Cmax was 37.8 ± 13.4 μg/ml (SDZ) and 1.92 ± 0.25 μg/ml (TMP). Tmax was 1.4 ± 0.6 hr (SDZ) and 1.4 ± 0.4 hr (TMP). Cmin for SDZ and TMP was 16.84 ± 8.46 μg/ml and 0.46 ± 0.24 μg/ml, respectively. Elimination half-life was 10.8 ± 6.1 hr (SDZ) and 6.5 ± 2 hr (TMP). AUC0 → ∞ was 667 ± 424 μg × hr/ml (SDZ) and 21.1 ± 5.3 μg × hr/ml (TMP). Foals remained healthy, and the plasma concentration of sulfadiazine-trimethoprim reached levels above MIC(90) for Streptococcus equi ssp. (SDZ/TMP): 9.5/0.5 μg/ml).

Therapeutic Drug Monitoring Is a Feasible Tool to Personalize Drug Administration in Neonates Using New Techniques: An Overview on the Pharmacokinetics and Pharmacodynamics in Neonatal Age

Therapeutic drug monitoring (TDM) should be adopted in all neonatal intensive care units (NICUs), where the most preterm and fragile babies are hospitalized and treated with many drugs, considering that organs and metabolic pathways undergo deep and progressive maturation processes after birth. Different developmental changes are involved in interindividual variability in response to drugs. A crucial point of TDM is the choice of the bioanalytical method and of the sample to use. TDM in neonates is primarily used for antibiotics, antifungals, and antiepileptic drugs in clinical practice. TDM appears to be particularly promising in specific populations: neonates who undergo therapeutic hypothermia or extracorporeal life support, preterm infants, infants who need a tailored dose of anticancer drugs. This review provides an overview of the latest advances in this field, showing options for a personalized therapy in newborns and infants.

Dosing of Antimicrobials in the Neonatal Intensive Care Unit: Does Clinical Practice Reflect Pharmacokinetics-based Recommendations?

BACKGROUND

We sought to compare meropenem and fluconazole dosing in the neonatal intensive care unit with recommendations based on published pharmacokinetic (PK) studies in infants.

METHODS

We performed an observational cohort study of infants <90 days postnatal age who received a course of meropenem or fluconazole who were treated in neonatal intensive care units managed by the Pediatrix Medical Group (1997-2016). We defined any dose amount from 80% to 120% of the published recommendation to constitute an appropriate dose of either antimicrobial. We calculated the percentage of appropriately dosed courses overall and by discharge year. We then evaluated the change in appropriate dosing over time using a nonparametric test of trend to evaluate the proportion of appropriately dosed courses of each antimicrobial by discharge year.

RESULTS

A total of 3608 infants were administered 2025 courses of meropenem and 1201 courses of fluconazole. Of all meropenem courses, 32% were dosed appropriately (increased significantly over time; P = 0.01), while 17% of fluconazole courses were dosed appropriately (increased significantly over time; P = 0.01). Median dosing for both meropenem and fluconazole was at or below recommendations; therefore, under-dosing was more common.

CONCLUSIONS

There was marked discordance between actual fluconazole and meropenem dosing and dosing recommendation in PK publications, yet adherence to PK-based doses showed improvement over time.

Flucloxacillin decreases tacrolimus blood trough levels: a single-center retrospective cohort study

Purpose

Tacrolimus and everolimus are widely used to prevent allograft rejection. Both are metabolized by the hepatic cytochrome P450 (CYP) enzyme CYP3A4 and are substrate for P-glycoprotein (P-gp). Drugs influencing the activity or expression of CYP enzymes and P-gp can cause clinically relevant changes in the metabolism of immunosuppressants. Several case reports have reported that flucloxacillin appeared to decrease levels of drugs metabolized by CYP3A4 and P-gp. The magnitude of this decrease has not been reported yet.

Methods

In this single-center retrospective cohort study, we compared the tacrolimus and everolimus blood trough levels (corrected for the dose) before, during, and after flucloxacillin treatment in eleven transplant patients (tacrolimus n = 11 patients, everolimus n = 1 patient, flucloxacillin n = 11 patients).

Results

The median tacrolimus blood trough level decreased by 37.5% (interquartile range, IQR 26.4–49.7%) during flucloxacillin treatment. After discontinuation of flucloxacillin, the tacrolimus blood trough levels increased by a median of 33.7% (IQR 22.5–51.4%). A Wilcoxon signed-rank test showed statistically significantly lower tacrolimus trough levels during treatment with flucloxacillin compared with before (p = 0.009) and after flucloxacillin treatment (p = 0.010). In the only available case with concomitant everolimus and flucloxacillin treatment, the same pattern was observed.

Conclusions

Flucloxacillin decreases tacrolimus trough levels, possibly through a CYP3A4 and/or P-gp-inducing effect. It is strongly recommended to closely monitor tacrolimus and everolimus trough levels during flucloxacillin treatment and up to 2 weeks after discontinuation of flucloxacillin.

Electronic supplementary material

The online version of this article (10.1007/s00228-020-02968-z) contains supplementary material, which is available to authorized users.

Complete Heart Block Secondary to Flecainide Toxicity: Is It Time for CYP2D6 Genotype Testing?

Flecainide acetate is a Vaughan-Williams class IC antiarrhythmic drug prescribed for the treatment of supraventricular arrhythmias. It has a narrow therapeutic index and proarrhythmic effects even at therapeutic doses. Flecainide is metabolized by a CYP2D6 enzyme that exhibits polymorphism. In this case report, we present, to our best knowledge, the first case of toxicity contributed by genetic polymorphism in an infant. Our patient with recurrent supraventricular tachycardia was treated with a therapeutic dose of flecainide but developed heart block requiring extracorporeal membrane oxygenation support and subsequent treatment with lipid emulsion therapy. He was found to have supratherapeutic serum flecainide concentration, and gene testing revealed the patient to be an intermediate metabolizer. With this case report, we reinforce the importance of evaluating the CYP2D6 genotype before drug initiation in the neonatal population and recommend regular monitoring of serum flecainide levels and electrocardiograms in these patients.

First dose in neonates: pharmacokinetic bridging study from juvenile mice to neonates for drugs metabolized by CYP3A

First dose prediction is challenging in neonates. Our objective in this proof-of-concept study was to perform a pharmacokinetic (PK) bridging study from juvenile mice to neonates for drugs metabolized by CYP3A. We selected midazolam and clindamycin as model drugs. We developed juvenile mice population PK models using NONMEM. The PK parameters of these two drugs in juvenile mice were used to bridge PK parameters in neonates using different correction methods. The bridging results were evaluated by the fold-error of 0.5- to 1.5-fold. Simple allometry with and without a correction factor for maximum lifespan potential could be used for a bridging of clearance (CL) and volume of distribution (V_d), respectively, from juvenile mice to neonates. Simulation results demonstrated that for midazolam, 100% of clinical studies for which both the predictive CL and V_d were within 0.5- to 1.5-fold of the observed. For clindamycin, 75% and 100% of clinical studies for which the predictive CL and V_d were within 0.5- to 1.5-fold of the observed. A PK bridging of drugs metabolized by CYP3A is feasible from juvenile mice to neonates. It could be a complement to the ADE and PBPK models to support the first dose in neonates.

Infantile inflammatory myofibroblastic tumors: clinicopathological and molecular characterization of 12 cases

Inflammatory myofibroblastic tumors arising in infants are rare, poorly investigated and mostly reported as isolated cases or as a part of larger series thus, their clinicopathological and molecular features are essentially unknown. Archival files from two large pediatric institutions and a tumor registry were queried for pediatric inflammatory myofibroblastic tumors. Available material from patients ≤12 months of age was reviewed. Additional immunostains (ALK-1, D240, WT1) and ALK-FISH studies were performed as needed. Targeted anchored multiplex PCR with next-generation sequencing was done in all cases. A total of 12 of 131 infantile cases (mean 5.5 months) were identified (M:F of 2:1). Anatomic locations included intestinal/mesenteric (n = 6), head/neck (n = 3), and viscera (n = 3). Half of tumors showed a hypocellular myxoid pattern, perivascular condensation, and prominent vasculature with vague glomeruloid structures present in four of them. The remaining cases exhibited a more cellular pattern with minimal myxoid component. ALK-1 immunohistochemistry was positive in most cases (11/12) with cytoplasmic-diffuse (n = 6), cytoplasmic-granular (n = 2), and dot-like (n = 3) staining patterns. ALK fusion partners identified in five cases included EML4, TPM4, RANBP2, and a novel KLC1. Three inflammatory myofibroblastic tumors showed fusions with other kinases including TFG-ROS1 and novel FN1-ROS1 and RBPMS-NTRK3 rearrangements. Favorable outcome was documented in most cases (10/11) with available follow-up (median 17 months) while three patients were successfully treated with crizotinib. In summary, infantile inflammatory myofibroblastic tumors are rare and can exhibit paucicellular, extensively myxoid/vascular morphology with peculiar immunophenotype mimicking other mesenchymal or vascular lesions. All tumors harbored kinase fusions involving ALK, ROS1, and NTRK3 including three novel fusion partners (KLC1, FN1, and RBPMS, respectively). A favorable response to crizotinib seen in three cases supports its potential use in infants as seen in older patients. Awareness of these unusual morphologic, immunophenotypic, and molecular features is critical for appropriate diagnosis and optimized targeted therapy.

Diuretic Use and Subsequent Electrolyte Supplementation in a Level IV Neonatal Intensive Care Unit

OBJECTIVES

To evaluate the relationship between diuretic use, serum electrolyte concentrations, and supplementation requirements in infants admitted to the neonatal intensive care unit.

METHODS

This was a single-center retrospective cohort study conducted in a freestanding children's hospital Level IV NICU. Data were collected for all infants younger than 6 months, admitted to the NICU between January 2015 and May 2017, who received 2 or more consecutive doses of furosemide, chlorothiazide, hydrochlorothiazide, and/or hydrochlorothiazide/spironolactone. The primary outcome was the composite of the incidence of electrolyte abnormalities and/or electrolyte supplementation requirement within 30 days of diuretic exposure.

RESULTS

A total of 72 patients met inclusion criteria, with a median gestational age of 30 weeks. Overall, 92% of patients exposed to diuretics experienced derangement in at least 1 serum electrolyte and/or required electrolyte supplementation during diuretic therapy. Patients born at 36 to 41 weeks' gestational age, receiving thiazide diuretics, experienced a significantly lower rate of the primary outcome (37%, p ≤ 0.001). The most common electrolytes affected by diuretic use were potassium and bicarbonate, with the highest incidence of the primary outcome for potassium occurring in patients receiving furosemide (p = 0.0196). Last, the median total daily dose of chlorothiazide in patients with an adverse event was 15 mg/kg/day, compared with 10 mg/kg/day in patients without an adverse event (p = 0.0041).

CONCLUSIONS

Use of diuretics in young infants is likely to cause electrolyte derangements and/or require electrolyte supplementation. Patients born at earlier gestational ages may be at higher risk for developing such adverse effects.

A LC-MS/MS method for the quantification of caffeine, betamethasone, clonidine and furosemide in cerebrospinal fluid of preterm infants

BACKGROUND

Newborns, admitted to the Neonatal Intensive Care Unit (NICU), are exposed to a large number of medications, the majority of which are not labeled for use in infants, especially in preterm newborns, because clinical trials on their benefits and harms are lacking. There is a huge gap in knowledge on pharmacokinetic (PK) data in sick preterm infants, including that of drug penetration to cerebrospinal fluid (CSF). One of the issues is related to the lack of reliable analytical methods for the measurement of drugs in CSF.

METHODS

In this paper we describe a specific and sensitive LC-MS/MS method for the simultaneous quantification in CSF of four commonly prescribed drugs in NICUs: caffeine, betamethasone, clonidine and furosemide.

RESULTS

The method was validated following EMA guidelines and applied to several CSF samples of preterm infants with post-hemorrhagic ventricular dilatation in which a ventricular access device was applied. The range of the concentrations of the four drugs measured in the CSF was wide.

CONCLUSIONS

Our method can be considered useful for further clinical studies to describe the PK aspects of these drugs in neonatal medicine.

Advanced nanotherapies to promote neuroregeneration in the injured newborn brain

Neonatal brain injury affects thousands of babies each year and may lead to long-term and permanent physical and neurological problems. Currently, therapeutic hypothermia is standard clinical care for term newborns with moderate to severe neonatal encephalopathy. Nevertheless, it is not completely protective, and additional strategies to restore and promote regeneration are urgently needed. One way to ensure recovery following injury to the immature brain is to augment endogenous regenerative pathways. However, novel strategies such as stem cell therapy, gene therapies and nanotechnology have not been adequately explored in this unique age group. In this perspective review, we describe current efforts that promote neuroprotection and potential targets that are unique to the developing brain, which can be leveraged to facilitate neuroregeneration.

Pediatric Formulations: Knowledge Gaps Limiting the Expedited Preclinical to Clinical Translation in Children

Traditionally, drug discovery and development research have been primarily focused on the mitigation of disease treatment for the general adult population, often overlooking the medical needs of pediatric patients. While remarkable progress toward the discovery of better medicines has been made, the pharmacological differences between children and adults are often neglected as part of the translation process. In fact, until recently, children have been considered therapeutic orphans due to the lack of significant drug discovery, formulation development, and dosage form design specifically tailored for pediatric patients. Perhaps the least understood is the significant physiological changes that occur during the maturation process from birth to adulthood. It requires careful considerations to achieve age-specific-desired therapeutic outcomes with minimal toxicity. This introduces considerable risk into the preclinical and clinical testing of new medicaments, which until recently, was avoided based on the conventional approach where a demonstration of safe and efficacious use in adults over several years potentially would minimize the chance of adverse juvenile responses. However, the lack of appropriate drug products for children has led to off-label use of adult medicines with potential life-threatening adverse reactions and health complications. Recent developments and future considerations regarding pediatric drug discovery and development using a patient-centric approach in the context of ontogenic biopharmaceutical considerations are discussed below.

First-Pass CYP3A-Mediated Metabolism of Midazolam in the Gut Wall and Liver in Preterm Neonates

To predict first‐pass and systemic cytochrome P450 (CYP) 3A‐mediated metabolism of midazolam in preterm neonates, a physiological population pharmacokinetic model was developed describing intestinal and hepatic midazolam clearance in preterm infants. On the basis of midazolam and 1‐OH‐midazolam concentrations from 37 preterm neonates (gestational age 26–34 weeks) receiving midazolam orally and/or via a 30‐minute intravenous infusion, intrinsic clearance in the gut wall and liver were found to be very low, with lower values in the gut wall (0.0196 and 6.7 L/h, respectively). This results in a highly variable and high total oral bioavailability of 92.1% (range, 67–95%) in preterm neonates, whereas this is around 30% in adults. This approach in which intestinal and hepatic clearance were separately estimated shows that the high bioavailability in preterm neonates is explained by, likely age‐related, low CYP3A activity in the liver and even lower CYP3A activity in the gut wall.

Accelerating drug development in pediatric cancer: a novel Phase I study design of venetoclax in relapsed/refractory malignancies

Venetoclax is a highly selective, potent BCL-2 inhibitor that is approved for some patients previously treated for chronic lymphocytic leukemia, and has shown promising activity in adult studies across several hematologic malignancies. Preclinical studies have demonstrated venetoclax activity in pediatric patient-derived xenograft models and cell lines; however, clinical studies in pediatric patients have yet to be conducted. The prognosis is poor for children with most relapsed/refractory malignancies, and limited treatment options result in unmet clinical need. Herein, we describe the rationale and design of the first study of venetoclax in pediatric patients with relapsed/refractory malignancies: a Phase I trial investigating the safety and pharmacokinetics of venetoclax monotherapy followed by the addition of chemotherapy (Trial registration: EudraCT 2017-000439-14; NCT03236857).

Coffee consumption and health: umbrella review of meta-analyses of multiple health outcomes

Objectives To evaluate the existing evidence for associations between coffee consumption and multiple health outcomes.Design Umbrella review of the evidence across meta-analyses of observational and interventional studies of coffee consumption and any health outcome.Data sources PubMed, Embase, CINAHL, Cochrane Database of Systematic Reviews, and screening of references.Eligibility criteria for selecting studies Meta-analyses of both observational and interventional studies that examined the associations between coffee consumption and any health outcome in any adult population in all countries and all settings. Studies of genetic polymorphisms for coffee metabolism were excluded.Results The umbrella review identified 201 meta-analyses of observational research with 67 unique health outcomes and 17 meta-analyses of interventional research with nine unique outcomes. Coffee consumption was more often associated with benefit than harm for a range of health outcomes across exposures including high versus low, any versus none, and one extra cup a day. There was evidence of a non-linear association between consumption and some outcomes, with summary estimates indicating largest relative risk reduction at intakes of three to four cups a day versus none, including all cause mortality (relative risk 0.83 (95% confidence interval 0.79 to 0.88), cardiovascular mortality (0.81, 0.72 to 0.90), and cardiovascular disease (0.85, 0.80 to 0.90). High versus low consumption was associated with an 18% lower risk of incident cancer (0.82, 0.74 to 0.89). Consumption was also associated with a lower risk of several specific cancers and neurological, metabolic, and liver conditions. Harmful associations were largely nullified by adequate adjustment for smoking, except in pregnancy, where high versus low/no consumption was associated with low birth weight (odds ratio 1.31, 95% confidence interval 1.03 to 1.67), preterm birth in the first (1.22, 1.00 to 1.49) and second (1.12, 1.02 to 1.22) trimester, and pregnancy loss (1.46, 1.06 to 1.99). There was also an association between coffee drinking and risk of fracture in women but not in men.Conclusion Coffee consumption seems generally safe within usual levels of intake, with summary estimates indicating largest risk reduction for various health outcomes at three to four cups a day, and more likely to benefit health than harm. Robust randomised controlled trials are needed to understand whether the observed associations are causal. Importantly, outside of pregnancy, existing evidence suggests that coffee could be tested as an intervention without significant risk of causing harm. Women at increased risk of fracture should possibly be excluded.

Guidance on the risk assessment of substances present in food intended for infants below 16 weeks of age

Following a request from the European Commission to EFSA, the EFSA Scientific Committee (SC) prepared a guidance for the risk assessment of substances present in food intended for infants below 16 weeks of age. In its approach to develop this guidance, the EFSA SC took into account, among others, (i) an exposure assessment based on infant formula as the only source of nutrition; (ii) knowledge of organ development in human infants, including the development of the gut, metabolic and excretory capacities, the brain and brain barriers, the immune system, the endocrine and reproductive systems; (iii) the overall toxicological profile of the substance identified through the standard toxicological tests, including critical effects; (iv) the relevance for the human infant of the neonatal experimental animal models used. The EFSA SC notes that during the period from birth up to 16 weeks, infants are expected to be exclusively fed on breast milk and/or infant formula. The EFSA SC views this period as the time where health-based guidance values for the general population do not apply without further considerations. High infant formula consumption per body weight is derived from 95th percentile consumption. The first weeks of life is the time of the highest relative consumption on a body weight basis. Therefore, when performing an exposure assessment, the EFSA SC proposes to use the high consumption value of 260 mL/kg bw per day. A decision tree approach is proposed that enables a risk assessment of substances present in food intended for infants below 16 weeks of age. The additional information needed when testing substances present in food for infants below 16 weeks of age and the approach to be taken for the risk assessment are on a case-by-case basis, depending on whether the substance is added intentionally to food and is systemically available.

Development and verification of a pharmacokinetic model to optimize physiologic replacement of rhIGF-1/rhIGFBP-3 in preterm infants

BACKGROUND

rhIGF-1/rhIGFBP-3 is being investigated for prevention of retinopathy of prematurity in extremely preterm infants.

METHODS

A population pharmacokinetic model was developed using data from phase I/II (Sections A-C) trials of rhIGF-1/rhIGFBP-3 and additional studies in preterm infants to predict optimal dosing to establish/maintain serum IGF-1 within physiological intrauterine levels. In Section D of the phase II study, infants (gestational age (GA) (wk+d) 23+0 to 27+6) were randomized to rhIGF-1/rhIGFBP-3, administered at the model-predicted dose of 250 µg/kg/d continuous i.v. infusion up to postmenstrual age (PMA) 29 wk+6 d or standard of care. An interim pharmacokinetic analysis was performed for the first 10 treated infants to verify dosing.

RESULTS

Serum IGF-1 data were reviewed for 10 treated/9 control infants. Duration of therapy in treated infants ranged 1-34.5 d. At baseline (before infusion and <24 h from birth), mean (SD) IGF-1 was 19.2 (8.0) μg/l (treated) and 15.4 (4.7) μg/l (controls). Mean (SD) IGF-1 increased to 45.9 (19.6) μg/l at 12 h in treated infants, and remained within target levels for all subsequent timepoints. For treated infants, 88.8% of the IGF-1 measurements were within target levels (controls, 11.1%).

CONCLUSION

Through the reported work, we determined appropriate rhIGF-1/rhIGFBP-3 dosing to achieve physiological intrauterine serum IGF-1 levels in extremely preterm infants.