Precision Dosing in Children

Beyond Population-Level Targets for Drug Concentrations: Precision Dosing Needs Individual-Level Targets that Include Superior Biomarkers of Drug Responses

The purpose of precision dosing is to increase the chances of therapeutic success in individual patients. This is achieved in practice by adjusting doses to reach precision dosing targets determined previously in relevant populations, ideally with robust supportive evidence showing improved clinical outcomes compared with standard dosing. But is this implicit assumption of translatable population-level precision dosing targets correct and the best for all patients? In this review, the types of precision dosing targets and how they are determined are outlined, problems with the translatability of these targets to individual patients are identified, and ways forward to address these challengers are proposed. Achieving improved clinical outcomes to support precision dosing over standard dosing is currently hampered by applying population-level targets to all patients. Just as "one-dose-fits-all" may be an inappropriate philosophy for drug treatment overall, a "one-target-fits-all" philosophy may limit the broad clinical benefits of precision dosing. Defining individual-level precision dosing targets may be needed for greatest therapeutic success. Superior future precision dosing targets will integrate several biomarkers that together account for the multiple sources of drug response variability.

Small patients, big challenges: navigating pediatric drug manipulations to prevent medication errors - a comprehensive review

INTRODUCTION

Medication errors during drug manipulations in pediatric care pose significant challenges to patient safety and optimal medication management. Epidemiological studies have revealed a high prevalenceof medication errors throughout the medication process. Due to the lack of age-appropriate dosage forms, medication manipulation is common in pediatric drug administration. The consequences of these manipulations on drug efficacy and safety could be devastating, highlighting the need for evidence-based guidelines and standardized compounding practices.

AREAS COVERED

This review focuses on examining medication errors in pediatric care and delving into the manipulation of medicinal products.

EXPERT OPINION

The observed prevalence of medication errors and manipulations underscores the importance of addressing these issues to enhance patient safety and improve medication outcomes in pediatric care. Overall, the development of age-appropriate formulations and the dissemination of comprehensive clinical guidelines are essential steps toward improving medication safety and minimizing manipulations in pediatric healthcare settings.

Translating Precision Health for Pediatrics: A Scoping Review

Precision health aims to personalize treatment and prevention strategies based on individual genetic differences. While it has significantly improved healthcare for specific patient groups, broader translation faces challenges with evidence development, evidence appraisal, and implementation. These challenges are compounded in child health as existing methods fail to incorporate the physiology and socio-biology unique to childhood. This scoping review synthesizes the existing literature on evidence development, appraisal, prioritization, and implementation of precision child health. PubMed, Scopus, Web of Science, and Embase were searched. The included articles were related to pediatrics, precision health, and the translational pathway. Articles were excluded if they were too narrow in scope. In total, 74 articles identified challenges and solutions for putting pediatric precision health interventions into practice. The literature reinforced the unique attributes of children and their implications for study design and identified major themes for the value assessment of precision health interventions for children, including clinical benefit, cost-effectiveness, stakeholder values and preferences, and ethics and equity. Tackling these identified challenges will require developing international data networks and guidelines, re-thinking methods for value assessment, and broadening stakeholder support for the effective implementation of precision health within healthcare organizations. This research was funded by the SickKids Precision Child Health Catalyst Grant.

Ibuprofen efficacy, tolerability and safety in obese children: a systematic review

OBJECTIVE

Childhood obesity can affect drug disposition and efficacy of ibuprofen. The primary objective was to assess efficacy of ibuprofen in obese children.

DESIGN

A systematic review was undertaken following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses methodology. Studies were identified from 12 databases. Two independent reviewers evaluated studies against the inclusion criteria and assessed for methodological quality.

SETTING

Any clinical setting.

PATIENTS

Patients under 18 years who were overweight/obese.

INTERVENTIONS

Patients taking ibuprofen for any indication, dose or regimen.

MAIN OUTCOME MEASURES

The efficacy and tolerability of ibuprofen treatment in obese children and presence of any adverse drug reactions.

RESULTS

Searches identified 1305 studies. Four studies met inclusion criteria: three retrospective cohort studies (n=583, median age: 6 years, range: 1-18 years; n=200, median age: 11 years, range: 3-18 years; n=358 median age: 3.1 years, range: 1.2-8.5 years, respectively) and one case study. Each study differed in their method of dosing ibuprofen (weight-based, age-based and adjusted body weight dosing). Various doses were used: 5 mg/kg every 6 hours, 400 mg three times a day, 120 mg/dose and a dose calculated using adjusted body weight. One study reported efficacy (obese n=189, non-obese, n=394), where adequate pain control was achieved using 5 mg/kg. The other three studies did not determine if efficacy differed between obese and non-obese children.One study described adverse effects. An increased risk of bleeding with ibuprofen was noted but did not differentiate between obese and non-obese children.

CONCLUSION

There are little published data to guide clinicians prescribing ibuprofen in obese children.

PROSPERO REGISTRATION NUMBER

CRD42021213500.

Population pharmacokinetic analysis of sildenafil in term and preterm infants with pulmonary arterial hypertension

Sildenafil is widely used off-label in pediatric patients with pulmonary arterial hypertension (PAH). This study was conducted to characterize the pharmacokinetics (PK) of sildenafil in term and preterm neonates with PAH, by developing a population PK model, and to suggest appropriate doses to achieve clinically effective concentrations. A population PK modelling analysis was performed using sildenafil and its metabolite N-desmethyl sildenafil (DMS) concentration data from 19 neonates with PAH, whose gestational ages ranged 24–41 weeks. They received sildenafil orally at a dose of 0.5–0.75 mg/kg, four times a day. To investigate the appropriate sildenafil dose, simulations were conducted according to body weight which was significant covariate for sildenafil clearance. A one-compartment model with first-order absorption adequately described the PKs of sildenafil and DMS. Sildenafil clearance was expected to increase rapidly with increasing body weight. In the simulation, sildenafil doses > 1 mg/kg was required to achieve and maintain target concentrations of sildenafil and to expect timely clinical effects in term and preterm infants. These results could be utilized for the safer and more effective use of sildenafil in term and preterm infants.

Plasma concentration guided dosing of drugs used for the treatment of childhood leukaemias: protocol for a systematic review

INTRODUCTION

Childhood leukaemia is the most common type of cancer in children and represents among 25% of the diagnoses in children <15 years old. Childhood survival rates have significantly improved within the last 40 years due to a rapid advancement in therapeutic interventions. However, in high-risk groups, survival rates remain poor. Pharmacokinetic (PK) data of cancer medications in children are limited and thus current dosing regimens are based on studies with small sample sizes. In adults, large variability in PK is observed and dose individualisation (plasma concentration guided dosing) has been associated with improved clinical outcomes; whether this is true for children is still unknown. This provides an opportunity to explore this strategy in children to potentially reduce toxicities and ensure optimal dosing. This paper will provide a protocol to systematically review studies that have used dose individualisation of drugs used in the treatment of childhood leukaemias.

METHODS AND ANALYSIS

Systematic review methodology will be applied to identify, select and extract data from published plasma guided dosing studies conducted in a paediatric leukaemia cohort. Databases (eg, Ovid Embase, Ovid MEDLINE, Ovid Cochrane) and clinical trial registries (CENTRAL, ClinicalTrials.gov and ISRCTN) will be used to perform the systematic literature search (up until February 2021). Only full empirical studies will be included, with primary clinical outcomes (progression-free survival, toxicities, minimal residual disease status, complete cytogenetic response, partial cytogenetic response and major molecular response) being used to decide whether the study will be included. The quality of included studies will be undertaken, with a subgroup analysis where appropriate.

ETHICS AND DISSEMINATION

This systematic review will not require ethics approval as there will not be collection of primary data. Findings of this review will be made available through publications in peer-reviewed journals and conference presentations. Gaps will be identified in current literature to inform future-related research.

PROSPERO REGISTRATION NUMBER

CRD42021225045.

Pharmacists' Approach to Optimise Safe Medication Use in Paediatric Patients

Paediatric patients are unique, yet challenging patients to care for by pharmacists. Paediatric medicine use requires special consideration. Pharmacists play an important role in educating and counselling patients, carers, and healthcare workers. Further, pharmacists have the necessary knowledge and skills to optimise safe medicine use in paediatric patients. This article provides basic principles for safe practices in paediatric medicine by following the nine rights of medication administration.

Status Toward the Implementation of Precision Dosing in Children

Precision dosing is progressing beyond the conceptual and proof-of-concept stages toward implementation. As the availability of dosing algorithms, tools, and platforms increases, so do the investment in technology services and actual implementation of clinical services offering these solutions to patients. Nowhere is this needed more than in pediatric populations, which are still reliant on adult drug development and bridging strategies to support dosing, often in the absence of actual dose-finding studies in the target pediatric population. Still, there is more work to be done to ensure that proper governance of these services is maintained, and that sustainability of these early implementations is guided by new science as it evolves and meaningful outcome data to confirm that such services deliver on both clinical and economic return on investment. In addition, the field should ensure that all approaches beyond a therapeutic drug monitoring-driven, pharmacokinetic-centric approach should be considered as the tools and services evolve, especially when pediatric-specific pharmacokinetic/pharmacodyamic and pharmacogenetic data are available and shown to be useful to guide dosing. This review evaluates current pediatric precision dosing efforts, highlighting their utility, longevity, and sustainability and assesses the current process for implementing such approaches examining current barriers that stand in the way of broader implementation and the stakeholders that must engage to ensure its ultimate success.

The Current Status of European and National Financial Sources for Clinical Research and Their Impact on Paediatric Non-commercial Clinical Trials: A Case Study of the Czech Republic

INTRODUCTION

Paediatric non-commercial interventional clinical trials (NICTs) are crucial for healthcare provision. In spite of the fact that current regulations and initiatives try to enhance the quantity and quality of paediatric NICTs, there are still shortcomings that need to be addressed in order to accelerate the conduct of relevant clinical trials in children. To improve the current landscape of paediatric clinical research, it is necessary to identify and analyse the main trends and shortcomings, along with their impact on national performance in paediatric NICTs and this is the aim of this work.

METHOD

A retrospective systematic search of paediatric NICTs was performed on four international clinical trials registries. Entries were filtered by date from 01/01/2004 to 31/12/2017. Each identified paediatric NICT was screened and analysed for sponsors, funders, type of intervention, therapeutic area, design characteristics and associated publications.

RESULTS

The search identified 439 unique NICTs. When stratifying the trials by enrolment ages, 86 trials were found involving the paediatric population. Most trials investigated the use of medicinal products and were focused on cancer or cardiovascular diseases. The most common sources of the funding were non-profit organizations. Furthermore, from the total number of completed trials, only half of them already published their results.

CONCLUSION

The main shortcomings-specifically, ethical, methodological and, in particular, economic obstacles were identified. There is a continual need for greater support and collaboration between all major stakeholders including health policymakers, grant agencies, research institutions, pharmaceutical industries and healthcare providers at the national and international level.

Spatial, Temporal, and Dose Control of Drug Delivery using Noninvasive Magnetic Stimulation

Noninvasive stimuli-responsive drug delivery using magnetic fields in conjunction with superparamagnetic nanoparticles offers the potential for the spatial and temporal control of drug release. When hyperthermia is not desired and control of the dosage is required, it is necessary to design a platform in which local heating on the nanoscale releases the therapeutic cargo without the bulk heating of the surrounding medium. In this paper, we report a design using a stimuli-responsive nanoparticle platform to control the dosage of the cargo released by an alternating magnetic field (AMF) actuation. A core@shell structure with a superparamagnetic doped iron oxide (MnFe₂O₄@CoFe₂O₄) nanoparticle core in a mesoporous silica shell was synthesized. The core used here has a high saturation magnetization value and a high specific loss power for heat generation under an AMF. The mesoporous shell has a high cargo-carrying capacity. A thermoresponsive molecular-based gatekeeper containing an aliphatic azo group was modified on the core@shell nanoparticles to regulate the cargo release. The mesoporous structure of the silica shell remained intact after exposure to an AMF, showing that the release of cargo is due to the removal of the gatekeepers instead of the destruction of the structure. Most importantly, we demonstrated that the amount of cargo released could be adjusted by the AMF exposure time. By applying multiple sequential exposures of AMF, we were able to release the cargo step-wise and increase the total amount of released cargo. In vitro studies showed that the death of pancreatic cancer cells treated by drug-loaded nanoparticles was controlled by different lengths of AMF exposure time due to different amount of drugs released from the carriers. The strategy developed here holds great promise for achieving the dosage, temporal, and spatial control of therapeutics delivery without the risk of overheating the particles' surroundings.

Optimizing the Dosing of Intravenous Theophylline in Acute Severe Asthma in Children

Optimizing the management of children presenting with acute severe asthma is of utmost importance to minimize hospital stays, morbidity, and mortality. Intravenous medications, including theophyllines, are used as second-line treatments for children experiencing a life-threatening exacerbation. For intravenous theophylline (aminophylline), guidelines and formularies recommend a target therapeutic range between 10 and 20 mg/l, with the commonest regimen being a loading dose of 5 mg/kg followed by an infusion calculated by age and weight. This review assesses the evidence underpinning these recommendations, highlighting the shortcomings in our understanding of the association between serum concentrations achieved, dose given, and clinical improvement experienced. To close the knowledge gap and improve outcomes for children presenting with acute severe asthma, we propose a series of research strategies to improve the assessment of illness severity, ascertain the optimal dose to maximize benefit and minimize risk, prospectively collect adverse events, and to better understand the inter-individual variation in responses to treatments.

Quantitation of salbutamol using micro-volume blood sampling - applications to exacerbations of pediatric asthma

OBJECTIVES

A novel gas chromatography-mass spectrometry (GC-MS) method has been developed to quantify salbutamol in micro-volumes (10 µL) of blood. A potential application is paediatric therapeutic dose monitoring (TDM) in acute severe asthma.

METHODS

At presentation, the children receive multiple doses of salbutamol (inhaled, nebulised and occasionally intravenous) but it is difficult to distinguish children who do not respond to treatment because of inadequate concentrations from those with toxicity, as symptoms are similar. A comparison was made between traditional dried blood spots (DBS) and the newly developed technique volumetric absorptive micro-sampling (VAMS), with specific investigation into the effect of drying time on analyte recovery.

RESULTS

For both sampling techniques, the final assay demonstrated good precision and accuracy across the concentration range tested (3-100 ng/mL), including both the normal therapeutic and toxic range. The method was developed to comply with FDA guidelines with precision and accuracy ≤15% for all concentrations, except the limit of quantification (5 ng/mL) where they were ≤20%. VAMS offered advantages in sampling ease and reduced GC-MS interference. The assay was successfully applied to the quantification of blood salbutamol concentrations in three healthy volunteers dosed with 1 mg salbutamol by inhalation.

CONCLUSIONS

This demonstrated its potential for use in paediatric TDM studies, where in the acute situation considerably higher doses of salbutamol will have been administered. This is the first time that a TDM method for salbutamol has been carried out using VAMS and offers all the advantages provided by DBS, whilst eliminating the inherent sampling volume inaccuracies of traditional DBS collection.

Using pharmacokinetic modelling to improve prescribing practices of intravenous aminophylline in childhood asthma exacerbations

OBJECTIVE

To evaluate physiologically based pharmacokinetic modelling (PBPK) software in paediatric asthma patients using intravenous aminophylline.

METHODS

Prospective clinical audit of children receiving iv aminophylline (July 2014 to June 2016), and in-silico modelling using Simcyp software.

RESULTS

Thirty-eight admissions (25 children) were included. Children with aminophylline levels ≥10 mg/l had equivalent clinical outcomes compared to those <10 mg/L, and adverse effects occurred in 57%. Therapeutic drug monitoring (TDM) data correlated well with PBPK model. PBPK modelling of a 5 mg/kg iv loading dose (≤18yr) shows a mean C_max of 8.99 mg/L (5th-95th centiles 5.5-13.7 mg/L), with 70.3% of subjects <10 mg/L, 29.4% achieving 10-20 mg/L, and 0.1% > 20 mg/L. For an aminophylline infusion (0-12 y) of 1.0  mg/kg/h, the mean steady state infusion concentration was 16.4 mg/L, (5th-95th centiles 5.3-32 mg/L), with 26.8% having a serum concentration >20 mg/L. For 12-18yr receiving 0.5  mg/kg/h infusion, the mean steady state infusion concentration was 9.37 mg/L (5th-95th centiles 3.4-18 mg/L), with 59.8% having a serum concentration <10 mg/L.

CONCLUSION

PBPK software modelling correlates well with clinical data. Current aminophylline iv loading dosage recommendations achieve levels <10 mg/l in 70% of children. Routine TDM may need altering as low risk of toxicity (>20 mg/l).

Aminophylline Dosage In Asthma Exacerbations in Children: A Systematic Review

BACKGROUND

Adequate asthma treatment of childhood exacerbations with IV aminophylline depends on appropriate dosage. Recommendations to aim for a target therapeutic range may be inappropriate as serum concentrations correlate poorly with clinical improvement. This review aims to evaluate the evidence for the optimum dosage strategy of intravenous aminophylline in children suffering an exacerbation of asthma.

METHODS

A systematic review comparing dosage regimens of intravenous aminophylline in children suffering an exacerbation of asthma. Primary outcomes were time until resolution of symptoms, mortality and need for mechanical ventilation. Secondary outcomes were date until discharge criteria are met, actual discharge and adverse effects.

DATA SOURCES

CENTRAL, CINAHL, MEDLINE and Web of Science. Search performed in March 2016.

ELIGIBILITY CRITERIA

Studies using intravenous aminophylline in children with an acute exacerbation of asthma which reported the dosage and clinical outcomes.

FINDINGS

14 RCTs were included. There is a poor relationship between the dosage administered to children and symptom resolution, length of stay or need for mechanical ventilation. This study is limited due to its use of indirect evidence.

CONCLUSION

The currently recommended dosage regimens may not represent the optimum safety and efficacy of intravenous aminophylline. There is a need to develop the evidence base correlating dosage with patient centered clinical outcomes, to improve prescribing practices.