Developmental population pharmacokinetics of caffeine in Chinese premature infants with apnoea of prematurity: A post-marketing study to support paediatric labelling in China

A small step toward precision dosing of caffeine in preterm infants: An external evaluation of published population pharmacokinetic models

BACKGROUND

Several population pharmacokinetic (PopPK) models of caffeine in preterm infants have been published, but the extrapolation of these models to facilitate model-informed precision dosing (MIPD) in clinical practice is uncertain. This study aimed to comprehensively evaluate their predictive performance using an external, independent dataset.

METHODS

Data used for external evaluation were based on an independent cohort of preterm infants. Currently available PopPK models for caffeine in preterm infants were identified and re-established. Prediction- and simulation-based diagnostics were used to assess model predictability. The influence of prior information was assessed using Bayesian forecasting.

RESULTS

120 plasma samples from 76 preterm infants were included in the evaluation dataset. Twelve PopPK models of caffeine in preterm infants were re-established based on our previously published study. Although two models showed superior predictive performance, none of the 12 PopPK models met all the clinical acceptance criteria of these external evaluation items. Besides, the external predictive performances of most models were unsatisfactory in prediction- and simulation-based diagnostics. Nevertheless, the application of Bayesian forecasting significantly improved the predictive performance, even with only one prior observation.

CONCLUSIONS

Two models that included the most covariates had the best predictive performance across all external assessments. Inclusion of different covariates, heterogeneity of preterm infant characteristics, and different study designs influenced predictive performance. Thorough evaluation is needed before these PopPK models can be implemented in clinical practice. The implementation of MIPD for caffeine in preterm infants could benefit from the combination of PopPK models and Bayesian forecasting as a helpful tool.

Effect of early preventive use of caffeine citrate on prevention together with treatment of BPD within premature infants and its influence on inflammatory factors

OBJECTIVE

To explore caffeine citrate prophylactic and therapeutic influences upon broncho-pulmonary dysplasia (BPD) within premature infants and its influence on inflammatory factors.

METHODS

A total of 128 premature infants from January 2021 to June 2022 were investigated, segregated within control group and observation group through randomized number table protocol, having 64 cases per group.

RESULTS

Effective rate of observation group was elevated in comparison to control group (95.31% versus 84.38%, P < 0.05). The number of apnea of prematurity (AOP) in observation group was reduced in comparison to control group, while duration of auxiliary ventilation together with hospitalization days were reduced in comparison to control group (P < 0.05). Post-therapy, matrix metalloproteinase-9 (MMP-9), tumor necrosis factor (TNF-α) and Toll-like receptor-4 (TLR-4) were downregulated within observation group, while scorings for psychomotor development index (PDI) and mental development index (MDI) in observation group were elevated in comparison to control group (P < 0.05). Weight-gain rate and growth rate of body length within observation group was elevated in comparison to control group (P < 0.05). Post-therapy, work of breathing (WOB) and airway resistance (Raw) within observation group were lower compared to control group, while respiratory system compliance (Crs) was elevated in comparison to control group (P < 0.05). Occurrences of broncho-pulmonary dysplasia (BPD) within observation group was reduced in comparison to control group (P < 0.05).

CONCLUSION

Early prophylactic use of caffeine citrate can effectively reduce the incidence of BPD in premature infants.

Development and application of a population pharmacokinetic model repository for caffeine dose tailoring in preterm infants

BACKGROUND

Considerable interindividual variability for the pharmacokinetics of caffeine in preterm infants has been demonstrated, emphasizing the importance of personalized dosing. This study aimed to develop and apply a repository of currently published population pharmacokinetic (PopPK) models of caffeine in preterm infants to facilitate model-informed precision dosing (MIPD).

RESEARCH DESIGN AND METHODS

Literature search was conducted using PubMed, Embase, Scopus, and Web of Science databases. Relevant publications were screened, and their quality was assessed. PopPK models were reestablished to develop the model repository. Covariate effects were evaluated and the concentration-time profiles were simulated. An online simulation and calculation tool was developed as an instance.

RESULTS

Twelve PopPK models were finally included in the repository. Preterm infants' age and body size, especially the postnatal age and current weight, were identified as the most clinically critical covariates. Simulated blood concentration-time profiles across these models were comparable. Caffeine citrate-dose regimen should be adjusted according to the age and body size of preterm infants. The developed online tool can be used to facilitate clinical decision-making.

CONCLUSIONS

The first developed repository of PopPK models for caffeine in preterm infants has a wide range of potential applications in the MIPD of caffeine.

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.

Modeling Developmental Changes in Caffeine Clearance Considering Differences between Pre- and Postnatal Period

Taguchi et al. reported that postmenstrual age (PMA) is a promising factor in describing and understanding the developmental change of caffeine (CAF) clearance. The aim of the present study was to quantify how developmental changes occur and to determine the effect of the length of the gestational period on CAF clearance. We performed a nonlinear mixed effect model (NONMEM) analysis and evaluated the fit of six models. A total of 115 samples were obtained from 52 patients with a mean age of 34.3 ± 18.2 d. The median values of gestational age (GA) and postnatal age (PNA) were 196 and 31 d, respectively. Serum CAF levels corrected for dose per body surface area (BSA) (C/D ratioBSA) were dependent on PMA rather than PNA, which supports the findings of a previous study. NONMEM analysis provided the following final model of oral clearance: CL/F = 0.00603∙WT∙∙0.877GA ≤ 196 L/h. This model takes into account developmental changes during prenatal and postnatal periods separately. The model successfully described the variation in clearance of CAF. Our findings suggest that the dosage of CAF in preterm infants should be determined based not only on body weight (WT) but also on both PNA and GA.

Temporal profile of adverse drug reactions and associated clinical factors: a prospective observational study in a neonatal intensive care unit

OBJECTIVE

Although adverse drug reactions (ADRs) are quite common in hospitalised neonates, pharmacovigilance activities in this public are still incipient. This study aims to characterise ADRs in neonates in a neonatal intensive care unit (NICU), identifying causative drugs, temporal profile and associated factors.

DESIGN

Prospective observational study.

SETTING

NICU of a public maternity hospital in Natal/Brazil.

PARTICIPANTS

All neonates admitted to the NICU for more than 24 hours and using at least one medication were followed up during the time of hospitalisation.

PRIMARY OUTCOME MEASURES

Incidence rate and risk factors for ADRs. The ADRs were detected by an active search in electronic medical records and analysis of spontaneous reports in the hospital pharmacovigilance system.

RESULTS

Six hundred neonates were included in the study, where 118 neonates had a total of 186 ADRs. The prevalence of ADRs at the NICU was 19.7% (95% CI 16.7% to 23.0%). The most common ADRs were tachycardia (30.6%), polyuria (9.1%) and hypokalaemia (8.6%). Tachycardia (peak incidence rate: 57.1 ADR/1000 neonates) and hyperthermia (19.1 ADR/1000 neonates) predominated during the first 5 days of hospitalisation. The incidence rate of polyuria and hypokalaemia increased markedly after the 20th day, with both reaching a peak of 120.0 ADR/1000 neonates. Longer hospitalisation time (OR 0.018, 95% CI 0.007 to 0.029; p<0.01) and number of prescribed drugs (OR 0.127, 95% CI 0.075 to 0.178; p<0.01) were factors associated with ADRs.

CONCLUSION

ADRs are very common in NICU, with tachycardia and hyperthermia predominant in the first week of hospitalisation and polyuria and hypokalaemia from the third week onwards.

Population pharmacokinetic modeling of caffeine in preterm infants with apnea of prematurity: New findings from concomitant erythromycin and AHR genetic polymorphisms

Current standard-dose caffeine therapy results in significant intersubject variability. The aims of this study were to develop and evaluate population pharmacokinetic (PPK) models of caffeine in preterm infants through comprehensive screening of covariates and then to propose model-informed precision dosing of caffeine for this population. A total of 129 caffeine concentrations from 96 premature neonates were incorporated into this study. Comprehensive medical record and genotype data of these neonates were collected for analysis. PPK modeling was performed by a nonlinear mixed effects modeling program (NONMEM). Final models based on the current weight (CW) or body surface area (BSA) were evaluated via multiple graphic and statistical methods. The model-informed dosing regimen was performed through Monte Carlo simulations. In addition to CW or BSA, postnatal age, coadministration with erythromycin (ERY), and aryl hydrocarbon receptor coding gene (AHR) variant (rs2158041) were incorporated into the final PPK models. Multiple evaluation results showed satisfactory prediction performance and stability of the CW- and BSA-based models. Monte Carlo simulations demonstrated that trough concentrations of caffeine in preterm infants would be affected by concomitant ERY therapy and rs2158041 under varying dose regimens. For the first time, ERY and rs2158041 were found to be associated with the clearance of caffeine in premature infants. Similar predictive performance and stability were obtained for both CW- and BSA-based PPK models. These findings provide novel insights into caffeine precision therapy for preterm infants.

Integrated in a systems pharmacology approach, pharmacogenetics holds the promise for personalized medicine in neonates

Tweetable abstract Integrated in a systems pharmacology approach, pharmacogenetics holds the promise for personalized medicine in neonates. This has been illustrated for some diseases specific to neonates.

Effectiveness and safety of early versus late caffeine therapy in managing apnoea of prematurity among preterm infants: a retrospective cohort study

BACKGROUND

Early administration of intravenous (IV) caffeine (initiation within 2 days of life) is an effective treatment strategy for the management of apnoea of prematurity among infants. However, the safety and effectiveness of early administration of oral caffeine treatment is not be fully established.

AIM

We aimed to compare the effectiveness and safety of early versus late caffeine therapy on preterm infants' clinical outcomes.

METHOD

A retrospective matched cohort study was conducted using data of patients admitted to neonatal intensive care units of two tertiary care hospitals between January 2016 and December 2018. The clinical outcomes and mortality risk between early caffeine (initiation within 2 days of life) and late caffeine (initiation ≥ 3 days of life) were compared.

RESULTS

Ninety-five pairs matched based on gestational age were included in the study. Compared to late initiation, preterm infants with early caffeine therapy had: a shorter duration of non-invasive mechanical ventilation (median 5 days vs. 12 days; p < 0.001); shorter length of hospital stay (median 26 days vs. 44 days; p  < 0.001); shorter duration to achieve full enteral feeding (median 5 days vs. 11 days; p < 0.001); and lower frequency of bronchopulmonary dysplasia (BPD) (4.5% vs. 12.9%; p = 0.045). They also had a reduced risk of osteopenia of prematurity (OP) (OR 0.209; 95% CI 0.085-0.509; p = 0.001).

CONCLUSION

Early oral caffeine therapy can potentially improve respiratory outcomes among infants with apnoea of prematurity. However, an increase in mortality associated with early caffeine therapy requires further investigation.

[Recent research on gene polymorphisms related to caffeine therapy in preterm infants with apnea of prematurity]

Apnea of prematurity (AOP) is one of the common diseases in preterm infants. The main cause of AOP is immature development of the respiratory control center. If AOP is not treated timely and effectively, it will lead to respiratory failure, hypoxic brain injury, and even death in severe cases. Caffeine is the first choice for the treatment of AOP, but its effectiveness varies in preterm infants. With the deepening of AOP research, more and more genetic factors have been confirmed to play important roles in the pathogenesis and treatment of AOP; in particular, the influence of single nucleotide polymorphism on the efficacy of caffeine has become a research hotspot in recent years. This article reviews the gene polymorphisms that affect the efficacy of caffeine, in order to provide a reference for individualized caffeine therapy. Citation.

The Impact of Pharmacogenetics on Pharmacokinetics and Pharmacodynamics in Neonates and Infants: A Systematic Review

In neonates, pharmacogenetics has an additional layer of complexity. This is because in addition to genetic variability in genes that code for proteins relevant to clinical pharmacology, there are rapidly maturational changes in these proteins. Consequently, pharmacotherapy in neonates has unique challenges. To provide a contemporary overview on pharmacogenetics in neonates, we conducted a systematic review to identify, describe and quantify the impact of pharmacogenetics on pharmacokinetics and -dynamics in neonates and infants (PROSPERO, CRD42022302029). The search was performed in Medline, Embase, Web of Science and Cochrane, and was extended by a PubMed search on the ‘top 100 Medicines’ (medicine + newborn/infant + pharmacogen*) prescribed to neonates. Following study selection (including data in infants, PGx related) and quality assessment (Newcastle–Ottawa scale, Joanna Briggs Institute tool), 55/789 records were retained. Retained records relate to metabolizing enzymes involved in phase I [cytochrome P450 (CYP1A2, CYP2A6, CYP2B6, CYP2C8/C9/C18, CYP2C19, CYP2D6, CYP3A5, CYP2E1)], phase II [glutathione-S-transferases, N-acetyl transferases, UDP-glucuronosyl-transferase], transporters [ATP-binding cassette transporters, organic cation transporters], or receptor/post-receptor mechanisms [opioid related receptor and post-receptor mechanisms, tumor necrosis factor, mitogen-activated protein kinase 8, vitamin binding protein diplotypes, corticotrophin-releasing hormone receptor-1, nuclear receptor subfamily-1, vitamin K epoxide reductase complex-1, and angiotensin converting enzyme variants]. Based on the available overview, we conclude that the majority of reported pharmacogenetic studies explore and extrapolate observations already described in older populations. Researchers commonly try to quantify the impact of these polymorphisms in small datasets of neonates or infants. In a next step, pharmacogenetic studies in neonatal life should go beyond confirmation of these associations and explore the impact of pharmacogenetics as a covariate limited to maturation of neonatal life (ie, fetal malformations, breastfeeding or clinical syndromes). The challenge is to identify the specific factors, genetic and non-genetic, that contribute to the best benefit/risk balance.

Caffeine for the Pharmacological Treatment of Apnea of Prematurity in the NICU: Dose Selection Conundrum, Therapeutic Drug Monitoring and Genetic Factors

Caffeine citrate is the drug of choice for the pharmacological treatment of apnea of prematurity. Factors such as maturity and genetic variation contribute to the interindividual variability in the clinical response to caffeine therapy in preterm infants, making the optimal dose administered controversial. Moreover, the necessity for therapeutic drug monitoring (TDM) of caffeine is still worth discussing due to the need to achieve the desired target concentrations as well as concerns about the safety of higher doses. Therefore, we reviewed the pharmacokinetic profile of caffeine in preterm infants, evidence of the safety and efficacy of different doses of caffeine, therapeutic concentration ranges of caffeine and impact of genetic variability on caffeine therapy. Whereas the safety and efficacy of standard-dose caffeine have been demonstrated, evidence for the safety of higher administered doses is insufficient. Thus, preterm infants who lack clinical response to standard-dose caffeine therapy are of interest for TDM when dose optimization is performed. Polymorphisms in pharmacodynamics-related genes, but not in pharmacokinetics-related genes, have a significant impact on the interindividual variability in clinical response to caffeine therapy. For preterm infants lacking clinical response, how to develop individualized medication regimens for caffeine remains to be explored.

Development of a Virtual Chinese Pediatric Population Physiological Model Targeting Specific Metabolism and Kidney Elimination Pathways

Background: Physiologically based pharmacokinetic (PBPK) modeling and simulating may be a powerful tool in predicting drug behaviors in specific populations. It is a mathematical model that relates the pharmacokinetic (PK) profile of a compound with human anatomical characteristics, physiological characteristics, and biochemical parameters. Predictions using PBPK models offer a promising way to guide drug development and can be used to optimize clinical dosing regimens. However, PK data of new drugs in the pediatric population are too limited to guide clinical therapy, which may lead to frequent adverse events or insufficient efficacy for pediatric patients, particularly in neonates and infants.

Objective: The objective of this study was to establish a virtual Chinese pediatric population based on the physiological parameters of Chinese children that could be utilized in PBPK models.

Methods: A Chinese pediatric PBPK model was developed in Simcyp Simulator by collecting published Chinese pediatric physiological and anthropometric data to use as system parameters. This pediatric population model was then evaluated in the Chinese pediatric population by predicting the pharmacokinetic characteristics of four probe drugs: theophylline (major CYP1A2 substrate), fentanyl (major CYP3A4 substrate), vancomycin, and ceftazidime (renal-eliminated).

Results: The predicted maximum concentration (C_max), area under the curve of concentration-time (AUC), and clearance (CL) for theophylline (CYP1A2 metabolism pathway) and fentanyl (CYP3A4 metabolism pathway) were within two folds of the observed data. For drugs mainly eliminated by renal clearance (vancomycin and ceftazidime) in the Chinese pediatric population, the ratio of prediction to observation for major PK parameters was within a 2-fold error range.

Conclusion: The model is a supplement to the previous Chinese population PBPK model. We anticipate the model to be a better representative of the pediatric Chinese population for drugs PK, offering greater clinical precision for medication given to the pediatric population, ultimately advancing clinical development of pediatric drugs. We can refine this model further by collecting more physiological parameters of Chinese children.