Exposure to the pharmaceutical excipients benzyl alcohol and propylene glycol among critically ill neonates

Exploring paediatric oral suspension development: Challenges, requirements, and formulation advancements

Oral suspension is the most preferred dosage form for the paediatric population because of the difficulties related to solid medications, such as the swallowing limitations, bitter taste, and poor oral bioavailability, which can cause serious impairment to attain a successful treatment. Given the importance of successful therapies, there is a need for safe and effective commercially-available paediatric oral suspension and their characterization. For the latter, it is important to identify safe excipients and preservatives. The paediatric group is a diverse category which includes infants and teenagers, with major pharmacokinetics and pharmacodynamics differences, mainly because of physiological and behavioral variations. Therefore, finding a single formulation for paediatric population remains a challenge, as well asthe formulation of stable-in-time suspension. In addition, drug's dissolving characteristic and permeation, are the main determinants for oral absorption, which are closely related to drug release kinetics from the pharmaceutical form. In this context, drug release profile is an important and limiting step in oral bioavailability, particularly for BCS class II drugs; thus, it is possible to increase bioavailability and minimize adverse effects by changing the release rate of such drugs. This review covers all the aspects for paediatric oral suspension development, and analyses the considerations for excipients selection as a crucial task for effectively choosing a safe and effective pharmaceutical form and correctly dosing paediatric patients.

Quantitative Investigation on Exposure to Potentially Harmful Excipients by Injection Drug Administration in Children Under 2 Years of Age and Analysis of Association with Adverse Events: A Single-Center, Retrospective Observational Study

INTRODUCTION

Potentially harmful excipients (PHEs) for children have been reported and the need for information collection has been advocated. However, studies on the actual occurrence of adverse events are limited. This study investigated the quantitative exposure of PHEs via injection and their association with adverse events in children under 2 years of age.

MATERIALS AND METHODS

As a single-center observational study, children aged 0-23 months received injectable drugs from April 1, 2018, to March 31, 2023 were included. Information on PHE exposure and adverse events after administration were extracted from medical records. Sodium benzoate, benzyl alcohol, ethanol, glycerol, lactose, polyethylene glycol paraben, polysorbate, propylene glycol, sorbitol, sucrose, sulfite, and thimerosal were selected as PHEs.

RESULTS AND DISCUSSION

6265 cases, 333,694 prescriptions, and 368 drugs (264 ingredients) were analyzed. The median age was 0.63 years (interquartile range [IQR] 0.1-1.1). 72,133 prescriptions, 132 drugs and 99 ingredients contained PHE; 2,961 cases exposed to PHE and 1825 cases exceeding permitted daily exposure. The drug with the highest number of exposure cases was hydroxyzine, and the highest number of prescriptions was heparin (both drugs contain benzyl alcohol). In association between adverse events and PHE exposure, higher doses in cases of adverse event occurrence were found in benzyl alcohol, glycerol, polyethylene glycol, and polysorbate exposed cases. Among thimerosal-exposed cases, "developmental delay" was more frequent in exposed cases, but the causal relationship was unknown. Further investigation is needed to clarify the relationship between adverse events and PHE exposure. Additionally, more precise information on PDE for pediatrics including neonates is necessary.

Perioperative exposure to volatile organic compounds in neonates undergoing cardiac surgery

OBJECTIVE

Volatile organic compounds (VOCs) are used in the sterilization and manufacture of medical equipment. These compounds have high vapor pressures with low water solubility and are emitted as gases from solids or liquids. They can be mutagenic, neurotoxic, genotoxic, and/or carcinogenic. Safe limits of exposure are not known for neonates. This study examined determinants of exposure in newborns undergoing cardiac surgery.

METHODS

Twenty metabolites of 16 VOCs (eg, xylene, cyanide, acrolein, acrylonitrile, N, N-dimethylformamide, 1,3-butadiene, styrene, and benzene) were measured as metabolites in daily urine samples collected from 10 neonates undergoing cardiac operations (n = 150 samples). Metabolites were quantified using reversed-phase ultra-high performance liquid chromatography and electrospray ionization tandem mass spectrometry. Repeated measures analysis of covariance was performed for each metabolite to examine associations with use of medical devices.

RESULTS

At least 3 metabolites were detected in every sample. The median number of metabolites detected in each sample was 14 (range, 3-15). In a model controlling for other factors, the use of extracorporeal membrane oxygenation was associated with significantly (P ≤ .05) greater metabolite levels of acrolein, acrylonitrile, ethylene oxide, propylene oxide, styrene, and ethylbenzene. Patients breathing ambient air had greater levels of metabolites of acrolein, xylene, N,N-dimethylformamide, methyl isocyanate, cyanide, 1,3-butadiene (all P ≤ .05).

CONCLUSIONS

Exposure to volatile organic compounds is pervasive in newborns undergoing cardiac surgery. Sources of exposure likely include medical devices and inhalation from the air in the intensive care unit. The contribution of VOC exposure during cardiac surgery in newborns to adverse outcomes warrants further evaluation.

Overcoming Challenges in Pediatric Formulation with a Patient-Centric Design Approach: A Proof-of-Concept Study on the Design of an Oral Solution of a Bitter Drug

Designing oral formulations for children is very challenging, especially considering their peculiarities and preferences. The choice of excipients, dosing volume and palatability are key issues of pediatric oral liquid medicines. The purpose of the present study is to develop an oral pediatric solution of a model bitter drug (ranitidine) following a patient centric design process which includes the definition of a target product profile (TPP). To conclude on the matching of the developed solution to TPP, its chemical and microbiological stability was analyzed over 30 days (stored at 4 °C and room temperature). Simulation of use was accomplished by removing a sample with a syringe every day. Taste masking was assessed by an electronic tongue. The developed formulation relied on a simple taste masking strategy consisting in a mixture of sweeteners (sodium saccharine and aspartame) and 0.1% sodium chloride, which allowed a higher bitterness masking effectiveness in comparison with simple syrup. The ranitidine solution was stable for 30 days stored at 4 °C. However, differences were noted between the stability protocols (unopened recipient and in-use stability) showing the contribution of the simulation of use to the formation of degradation products. Stock solution was subjected to acid and alkali hydrolysis, chemical oxidation, heat degradation and a photo degradation stability assessment. The developed pediatric solution matched the TPP in all dimensions, namely composition suitable for children, preparation and handling adapted to hospital pharmaceutical compounding and adequate stability and quality. According to the results, in-use stability protocols should be preferred in the stability evaluation of pediatric formulations.

Effective low-dose sirolimus regimen for kaposiform haemangioendothelioma with Kasabach-Merritt phenomenon in young infants

AIMS

Management of kaposiform haemangioendotheliomas (KHE) with Kasabach-Merritt phenomenon is challenging in young infants who are subjected to developmental pharmacokinetic changes. Sirolimus, sometimes combined with corticosteroids, can be used as an effective treatment of KHE. Simultaneously, toxicities such as interstitial pneumonitis related to the use of sirolimus may be fatal. As infants have a very low CYP3-enzyme expression at birth, which rises during ageing, we hypothesize that a reduced metabolization of sirolimus might lead to high sirolimus serum levels and low dose may be sufficient without the side effects.

METHODS

A case series of 5 infants with kaposiform haemangioendothelioma with Kasabach-Merritt phenomenon was analysed retrospectively. All infants were treated with sirolimus 0.2 mg/m2 every 24 or 48 hours according to their age. Prednisone was added to the therapy for additional effect in 4 patients.

RESULTS

In all patients, low dose of sirolimus led to therapeutic sirolimus levels (4-6 ng/mL). All infants (aged 4 days-7 months) had a complete haematological response, without serious adverse events. In all patients, the Kasabach-Merritt phenomenon resolved, the coagulation profile normalized and tumour size reduction was seen.

CONCLUSION

Low-dose sirolimus treatment is safe for infants with kaposiform haemangioendothelioma and Kasabach-Merritt phenomenon. It is essential to realize that during the first months of life, metabolism is still developing and enzymes necessary to metabolise drugs like sirolimus still have to mature. To avoid toxic levels, the sirolimus dosage should be based on age and the associated pharmacological developments.

Chronic kidney disease, pregnancy and haemodialysis: Case reports from a single centre in Kenya and literature review

Chronic kidney disease (CKD) and end stage kidney disease are prevalent even in women of reproductive age. These are known to reduce fertility and successful pregnancy. There are chances of conception even in advanced CKD, though laden with complications. We present two cases of women who conceived in advanced CKD and were on haemodialysis in a tertiary hospital in Kenya, and review of literature.

The Current States, Challenges, Ongoing Efforts, and Future Perspectives of Pharmaceutical Excipients in Pediatric Patients in Each Country and Region

A major hurdle in pediatric formulation development is the lack of safety and toxicity data on some of the commonly used excipients. While the maximum oral safe dose for several kinds of excipients is known in the adult population, the doses in pediatric patients, including preterm neonates, are not established yet due to the lack of evidence-based data. This paper consists of four parts: (1) country-specific perspectives in different parts of the world (current state, challenges in excipients, and ongoing efforts) for ensuring the use of safe excipients, (2) comparing and contrasting the country-specific perspectives, (3) past and ongoing collaborative efforts, and (4) future perspectives on excipients for pediatric formulation. The regulatory process for pharmaceutical excipients has been developed. However, there are gaps between each region where a lack of information and an insufficient regulation process was found. Ongoing efforts include raising issues on excipient exposure, building a region-specific database, and improving excipient regulation; however, there is a lack of evidence-based information on safety for the pediatric population. More progress on clear safety limits, quantitative information on excipients of concern in the pediatric population, and international harmonization of excipients’ regulatory processes for the pediatric population are required.

Potentially harmful excipients in neonatal medications: a multicenter nationwide observational study in Japan

Background

A multicenter investigation of neonate exposure to potentially harmful excipients (PHEs) in neonatal intensive care units (NICUs) in Japan has not been conducted.

Methods

A multicenter nationwide observational study was conducted. Neonate patient demographic data and information on all medicines prescribed and administered during hospitalization on 1 day between November 2019 and March 2021 were extracted from the medical records. Nine PHEs, paraben, polysorbate 80, propylene glycol, benzoates, saccharin sodium, sorbitol, ethanol, benzalkonium chloride, and aspartame, were selected. PHEs were identified from the package insert and the Interview Form. The quantitative daily exposure was calculated if quantitative data were available for each product containing the PHE.

Results

Prescription data was collected from 22 NICUs in Japan. In total, 343 neonates received 2360 prescriptions for 426 products containing 228 active pharmaceutical ingredients. PHEs were found in 52 (12.2%) products in 646 (27.4%) prescriptions for 282 (82.2%) neonates. Benzyl alcohol, sodium benzoates, and parabens were the most common PHEs in parenteral, enteral, and topical formulations, respectively. Quantitative analysis showed that 10 (10%), 38 (42.2%), 37 (94.9%), and 9 (39.1%) neonates received doses exceeding the acceptable daily intake of benzyl alcohol, polysorbate 80, propylene glycol, and sorbitol, respectively. However, due to the lack of quantitative information for all enteral and topical products, accurate daily PHE exposure could not be quantified.

Conclusions

Neonates admitted to NICUs in Japan were exposed to PHEs, and several of the most commonly prescribed medicines in daily clinical practice in NICUs contained PHEs. Neonate PHE exposure could be reduced by replacing these medicines with available PHE-free alternatives.

MR Spectroscopy Shows Long Propylene Glycol Half-Life in Neonatal Brain

INTRODUCTION

Neonatal propylene glycol (PG) clearance is low with long plasma half-life. We hypothesized that neonatal brain PG clearance is diminished and may be related to perinatal asphyxia, infection, or stroke, via different blood-brain barrier permeability. This study aimed to estimate cerebral PG half-life with a clearance model including PG measured with MR spectroscopy (MRS) in neonates that received phenobarbital as the only PG source and to evaluate whether PG clearance was related to intracerebral pathology, for example, perinatal asphyxia, infection, or stroke.

METHODS

In this retrospective cohort study, 45 neonates receiving any dose of phenobarbital underwent MRS (short echo time single-voxel MRS at 1.5 T). Cumulative phenobarbital/PG doses were calculated. MRS indications were perinatal asphyxia (n = 22), infection (n = 4), stroke (n = 10), metabolic disease (n = 4), and others (n = 5).

RESULTS

Medians (interquartile range) included gestational age 39.4 (3.1) weeks, birth weight 3,146 (1,340) g, and cumulative PG dose 700 (1,120) mg/kg. First-order kinetics with mono-exponential decay showed cerebral PG half-life of 40.7 h and volume of distribution of 1.6 L/kg. Zero-order kinetics showed a rate constant of 0.048 mM/h and a volume of distribution of 2.3 L/kg, but the fit had larger residuals than the first-order model. There were no differences in ΔPG (i.e., PG estimated with clearance model minus PG observed with MRS) in infants with perinatal asphyxia, infection, or stroke.

DISCUSSION/CONCLUSION

This study showed a long cerebral PG half-life of 40.7 h in neonates, unrelated to perinatal asphyxia, infection, or stroke. These findings should increase awareness of possible toxic PG concentrations in neonatal brain due to intravenous PG-containing drugs.

Possible effects of excipients used in the parenteral drugs administered in critically ill adults, children, and neonates

BACKGROUND

Critically ill patients receiving parenteral drugs are at an increased risk of exposure to various excipients administered simultaneously and at increased amounts. Hence, we carried out the present study.

RESEARCH DESIGN AND METHODS

Patients admitted in the adult, pediatric, and neonatal intensive care units were recruited following their consent. Details on their demographics, diagnoses, and drugs administered and the excipients were collected.

RESULTS

Almost all the critically ill patients received drugs containing at least one excipient. Significant numbers of critically ill neonates received at least one of either known to be harmful or potentially harmful excipients. Critically ill neonates had significantly greater daily exposure of macrogol than children and adults; and benzyl alcohol (v/v) and propyl paraben compared to adults. Critically ill neonates and children had greater exposure to benzyl alcohol (w/v), methyl paraben, sodium metabisulfite than adults did. Benzyl alcohol exposure was likely to be several-fold high in critically ill patients. Exposures to benzyl alcohol and propylene glycol were possibly linked to increased risk of mortality particularly in neonates.

CONCLUSION

Critically ill neonates and children are likely to receive a significantly greater quantity of harmful excipients than critically ill adults. Benzyl alcohol and propylene glycol exposure are likely to be associated with increased risk of mortality in critically ill.

Availability of age-appropriate paediatric formulations in the Netherlands: the need in daily clinical practice remains

Objectives

To quantify the availability of authorised, age-appropriate paediatric medicines in clinical practice in the Netherlands and to identify gaps by assessing dispensing practice in a paediatric hospital.

Methods

The availability of age-appropriate formulations was assessed by conducting a survey on the use of pharmacy compounded medicines among the paediatric hospitals in the Netherlands, and by analysing dispensing data of oral medication from the inpatient pharmacy of the largest paediatric hospital in the Netherlands. The age-appropriateness of the dispensed formulations was assessed on two aspects: dose-capability and acceptability. Liquid drug products that are unsuitable due to the presence of potentially harmful excipients, were identified based on the dosage in clinical practice.

Results

For 129 out of 139 drug substances included in the survey (93%), at least one of the eight respondents stated to use a pharmacy compounded product to meet the needs of their paediatric patients. The age-appropriateness of medicines dispensed from the inpatient pharmacy increased with age, and was higher for non-intensive care unit (ICU) patients than for ICU patients. We identified 15 drug products causing excipient exposure above the European Medicines Agency-recommended values.

Conclusions

This study confirms there is still a large need for age-appropriate formulations in daily clinical practice. Pharmacy compounding for paediatric patients remains essential for many indications. The need for potentially harmful excipients in compounded products should be critically assessed.

Potential consequences of high-dose infusion of ketamine for refractory status epilepticus: case reports and systematic literature review

Our goal was to provide comprehensive data on the effectiveness of ketamine in refractory status epilepticus (RSE) and to describe the potential consequences of long-term ketamine infusion. Ketamine, an N-methyl D-aspartate (NMDA) receptor antagonist, blocks excitatory pathways contributing to ongoing seizure. While ketamine use is standard in anaesthetic induction, no definitive protocol exists for its use in RSE, and little is known about its adverse effects in long-term, high-dose administration. We present two cases of RSE that responded rapidly to ketamine infusion, both with fatal outcomes secondary to metabolic acidosis and cardiovascular collapse. We performed a systematic review of the application and consequences of ketamine use in RSE. PubMed, Ovid, MEDLINE and PMC were searched for articles describing ketamine treatment for RSE according to a predetermined search strategy and inclusion criteria. The systematic review revealed wide discrepancies in ketamine dosing (infusion maintenance dose range 0.0075-10.5 mg/kg/hour), but good outcomes in medically managed RSE (75% of studies reported moderate or complete seizure control in adults, 62.5% in paediatrics). Additionally, literature review elucidated a potentially causal relationship between prolonged ketamine infusion and both cardiovascular and metabolic dysregulation. Ketamine is effective in RSE by antagonising excitotoxic NMDA receptors. However, there is high variability in ketamine dosing and scarce data on its safety in long-term infusion. Metabolic acidosis and haemodynamic instability associated with the use of long-term, high-dose ketamine infusions must be of concern to clinicians administering ketamine to critically ill patients.

Spectroscopic detection of brain propylene glycol in neonates: Effects of different pharmaceutical formulations of phenobarbital

Background

The first choice for treatment of neonatal convulsions is intravenous phenobarbital, which contains propylene glycol (PG) as a solvent. Although PG is generally considered safe, the dosage can exceed safety thresholds in neonates. High PG levels can cause lactic acidosis.

Purpose/Hypothesis

To investigate a relationship between brain PG concentration and medication administered to neonates, and to study if a correlation between spectroscopically detected PG and lactate was present.

Study Type

Retrospective.

Population

Forty‐one neonates who underwent MRI/MRS.

Field Strength/Sequence

Short echo time single voxel MRS at 1.5T.

Assessment

Spectra were quantified. Concentrations of PG were correlated with medication administered, because intravenously administered phenobarbital solutions contained 10, 25, or 50 mg phenobarbital per ml, all containing 350 mg PG per ml. The interval between medication and MRI/MRS was determined.

Statistical Tests

Chi‐square test, Student's t‐test, Mann–Whitney U‐test and Spearman correlation.

Results

Eighteen neonates had brain PG >1 mM (median 3.4 mM, maximum 9.5 mM). All 18 neonates with high brain PG and 14 neonates with low brain PG (<1 mM) received phenobarbital as the only source of PG. Nine neonates did not receive any phenobarbital/PG‐containing medication. Neonates with high brain PG more often received 10 mg/ml phenobarbital, resulting in higher PG dose (high vs. low brain PG (median [interquartile range]: 1400 [595] vs. 350 [595] mg/kg, respectively, P < 0.01). In addition, the interval between the last phenobarbital dose and MRI was shorter in the high brain PG group (high vs. low brain PG: 16 [21] vs. 95 [83] hours, respectively, P < 0.001). Within neonates that received phenobarbital, there was no conclusive correlation between spectroscopically detected PG and lactate (Spearman's rho = 0.23, P = 0.10).

Data Conclusion

These MRS findings may increase awareness of potentially toxic PG concentrations in the neonatal brain due to intravenous phenobarbital administration and its dependence on the phenobarbital formulation used.

Level of Evidence: 4

Technical Efficacy: Stage 5

J. Magn. Reson. Imaging 2019;49:1062–1068.

Excipients in Neonatal Medicinal Products: Never Prescribed, Commonly Administered

To attain effective and safe pharmacotherapy, formulations in (pre)term neonates should enable extensive dose flexibility. During product development and subsequent authorization and clinical use of such formulations, there is also a need for informed decisions on excipient exposure: in addition to the need to improve the knowledge on active compounds, there is a similar need to improve the knowledge on excipients in neonates. Excipients are added to formulations as co-solvent, surfactant, preservative, colorant and/or sweetener as vehicle(s) to result in a suitable (e.g. taste, shelf life, stability) product. Progress has been made in the awareness, knowledge and access to this knowledge on the clinical pharmacology of excipients in neonates. This is thanks to different initiatives focussing on epidemiological data, excipient pharmacokinetics, or building datasets to create this knowledge. We highlight the Safe Excipient Exposure in Neonates and Small Children (SEEN) and propylene glycol project to illustrate the feasibility to build knowledge, and discuss the methods applied and problems observed during these studies. The information generated in these and other studies (European Study on Neonatal Exposure to Excipients, ESNEE) should be integrated in repositories like the Safety and Toxicity of Excipients for Paediatrics (STEP) to facilitate access to all stakeholders. This merged knowledge should have impact and assist in improving the quality of risk assessment and decision making during drug development, applying a risk-benefit framework (explicit justification of excipients, plan product development early and engage all stakeholders, data sharing and modeling, challenges related to new excipients, context sensitive risk-benefit analysis).

Safety Assessment of Benzyl Alcohol, Benzoic Acid and its Salts, and Benzyl Benzoate

Benzyl alcohol, benzoic acid and its salts, and benzyl benzoate function mostly as fragrance ingredients/preservatives in cosmetic products. The Cosmetic Ingredient Review Expert Panel previously established concentration limits for benzyl alcohol, benzoic acid, and sodium benzoate in cosmetics and determined that the available data were insufficient to support the safety of these ingredients during inhalation exposure. After reviewing newly available data, it was concluded that benzyl alcohol, benzoic acid and its salts, and benzyl benzoate are safe in the present practices of use and concentration described in this safety assessment.

A Trimethoprim Conjugate of Thiomaltose Has Enhanced Antibacterial Efficacy In Vivo

Trimethoprim is one of the most widely used antibiotics in the world. However, its efficacy is frequently limited by its poor water solubility and dose limiting toxicity. Prodrug strategies based on conjugation of oligosaccharides to trimethoprim have great potential for increasing the solubility of trimethoprim and lowering its toxicity, but they have been challenging to develop due to the sensitivity of trimethoprim to chemical modifications, and the rapid degradation of oligosaccharides in serum. In this report, we present a trimethoprim conjugate of maltodextrin termed TM-TMP, which increased the water solubility of trimethoprim by over 100 times, was stable to serum enzymes, and was active against urinary tract infections in mice. TM-TMP is composed of thiomaltose conjugated to trimethoprim, via a self-immolative disulfide linkage, and releases 4'-OH-trimethoprim (TMP-OH) after disulfide cleavage, which is a known metabolic product of trimethoprim and is as potent as trimethoprim. TM-TMP also contains a new maltodextrin targeting ligand composed of thiomaltose, which is stable to hydrolysis by serum amylases and therefore has the metabolic stability needed for in vivo use. TM-TMP has the potential to significantly improve the treatment of a wide number of infections given its high water solubility and the widespread use of trimethoprim.

Excipient exposure in very low birth weight preterm neonates

OBJECTIVE

The excipients benzyl alcohol, propylene glycol and ethanol are present in medications used in the neonatal intensive care unit. Exposure to high levels can have adverse effects in a neonatal population. The objective was to quantify excipient exposure in very low birth weight (VLBW) neonates and identify risk factors associated with greater exposure.

STUDY DESIGN

A retrospective record review of VLBW infants admitted over 1 year. Excipient exposures were calculated and multivariable regression analyses identified risk factors for increasing exposure.

RESULTS

In total, 98% of subjects were exposed to at least one excipient. A total of 5 to 9% received doses higher than recommended for adults. Necrotizing enterocolitis, seizure, bronchopulmonary dysplasia and longer stay predicted higher excipient exposure.

CONCLUSION

The excipients examined are in medications commonly prescribed for VLBW neonates, and cumulative doses may exceed recommended exposures for adults. Although safety profiles have not been established, judicious use of medication containing these excipients is warranted for this population.

Pregnancy and End-Stage Renal Disease

Pregnancy is uncommon in women with end-stage renal disease (ESRD). Fertility rates are low in women on dialysis, and physicians still frequently counsel women with ESRD against pregnancy. Advancements in the delivery of dialysis and obstetric care have led to improved live birth rates in women on dialysis, so pregnancy for young women with ESRD is now more feasible and safer. However, these pregnancies remain high-risk for both maternal and fetal complications, necessitating experienced multidisciplinary care. In this article, we review fertility issues in women with ESRD, discuss pregnancy outcomes in women on dialysis, and provide an approach for management of pregnant women with ESRD.

The Cumulative Daily Tolerance Levels of Potentially Toxic Excipients Ethanol and Propylene Glycol Are Commonly Exceeded in Neonates and Infants

Polymedicated neonates and young infants may be at risk of harmful cumulative exposure to toxic excipients like ethanol, propylene glycol and benzyl alcohol during routine clinical care. The aim of this study was to calculate the cumulative daily alcohol exposure (mg/kg/day) in polymedicated neonates and infants and compare these levels to the tolerance limits found in guidelines published by European Medicines Agency (EMA). As part of the SEEN study, all medicinal products administered to neonates and infants were recorded. All included neonates received ≥2 medicinal products/day and infants ≥3 medicinal products/day. Daily excipient levels were calculated based on quantities obtained from manufacturers or databases. Excipient levels were compared to tolerance limits proposed by the EMA. Altogether, 470 neonates and 160 infants were included, recording 4207 prescriptions and 316 products. In total, 45% (n = 288) of patients were exposed to an alcohol of interest; 2% (n = 14) were exposed to benzyl alcohol (BA), 38% (n = 237) to ethanol and 23% (n = 146) to propylene glycol (PG). Of the total number of prescriptions involving ethanol-containing medicinal products (n = 334), 51% would alone exceed tolerance limit of 6 mg/kg/day. Of the total number of prescriptions involving PG-containing medicinal products (n = 174), 70% would alone exceed a maximum tolerance limit of 50 mg/kg/day. Maximal daily exposure to ethanol (1563 mg/kg/day) or PG (954 mg/kg/day) exceeded the tolerance limits recommended by EMA 260.5 and 19.1 times, respectively. Tolerance limits for ethanol and PG as proposed by the EMA are frequently exceeded in polymedicated neonates and infants due to the cumulative effect of these alcohols. Alternative formulations may minimize excipient exposure.

Propylene Glycol Toxicity in Adolescent with Refractory Myoclonic Status Epilepticus

Propylene glycol (PG) is a solvent commonly used in medications that, while benign at low doses, may cause toxicity in adults and children at high doses. We describe a case and the physiologic sequelae of propylene glycol toxicity manifested in a critically ill adolescent male with refractory myoclonic status epilepticus aggressively treated with multiple PG-containing medications (lorazepam, phenobarbital, and pentobarbital)—all within accepted dosing guidelines and a total daily PG exposure previously recognized to be safe. Hemodynamic measurements by bedside echocardiography during clinical toxicity are also reported. Clinicians should have a high index of suspicion for propylene glycol toxicity in patients treated with PG-containing medications even when the total PG exposure is lower than currently accepted limits.

A retrospective and observational analysis of harmful excipients in medicines for hospitalised neonates in Latvia

Background

Medicines used in neonates contain different excipients, which may not be safe in this age group.

Objective

To analyse the frequency at which hospitalised neonates are exposed to harmful excipients (HEs) and to identify substitution possibilities for medicines containing HEs.

Materials and methods

Retrospective, observational study at a university paediatric hospital from 1 September 2015 till 29 February 2016. All hospitalised neonates who received a prescription for medicines containing an HE were included. Neonates were divided into four groups according to gestational age (<28 weeks; 28 to <32 weeks; 32 to <37 weeks and ≥37 weeks). The following excipients were analysed: parabens, polysorbate 80, propylene glycol, benzoates, saccharin sodium, sorbitol, ethanol and benzalkonium chloride. Excipients were identified from the Summaries of Product Characteristics.

Results

296 (102(34.5%) preterm) neonates included in the study received 1472 prescriptions for 106 medicines. The most often used formulations were intravenous (48/106; 45.3%) and oral solid formulations (20; 18.9%). The total number of different excipients was 169. In total, 29/106 (27.4%) medicines contained at least one HE. In total 82/102 (80.4%) preterm and 118/194 (60.8%) term neonates received medications with at least one HE. Substitution was possible for 9/29 (31.0%) HE-containing medicines.

Conclusions

Use of HEs can be reduced by using HE-free products available on the European market. However, medicine substitution was possible in only a small number of cases. Therefore the main focus should be on information and education of the hospital specialists about HEs used in medicines and their adverse reactions.

Preterm neonatal urinary renal developmental and acute kidney injury metabolomic profiling: an exploratory study

BACKGROUND

Acute kidney injury (AKI) staging has been developed in the adult and pediatric populations, but these do not yet exist for the neonatal population. Metabolomics was utilized to uncover biomarkers of normal and AKI-associated renal function in preterm infants. The study comprised 20 preterm infants with an AKI diagnosis who were matched by gestational age and gender to 20 infants without an AKI diagnosis.

METHODS

Urine samples from pre-term newborn infants collected on day 2 of life were analyzed using broad-spectrum nuclear magnetic resonance (NMR) metabolomics. Multivariate analysis methods were used to identify metabolite profiles that differentiated AKI and no AKI, and to identify a metabolomics profile correlating with gestational age in infants with and without AKI.

RESULTS

There was a clear distinction between the AKI and no-AKI profiles. Two previously identified biomarkers of AKI, hippurate and homovanillate, differentiated AKI from no-AKI profiles. Pathway analysis revealed similarities to cholinergic neurons, prenatal nicotine exposure on pancreatic β cells, and amitraz-induced inhibition of insulin secretion. Additionally, a pH difference was noted. Both pH and the metabolites were found to be associated with AKI; however, only the metabotype was a significant predictor of AKI. Pathways for the no-AKI group that correlated uniquely with gestational age included aminoacyl-t-RNA biosynthesis, whereas pathways in the AKI group yielded potential metabolite changes in pyruvate metabolism.

CONCLUSIONS

Metabolomics was able to differentiate the urinary profiles of neonates with and without an AKI diagnosis and metabolic developmental profiles correlated with gestational age. Further studies in larger cohorts are needed to validate these results.

Compatibility of caffeine, carvedilol, clomipramine hydrochloride, folic acid, hydrochlorothiazide, loperamide hydrochloride, methotrexate, nadolol, naltrexone hydrochloride and pentoxifylline in SyrSpend SF PH4 oral suspensions

Objectives

The objective of this study was to evaluate the compatibility of 10 commonly used active pharmaceutical ingredients (APIs) compounded in oral suspensions using a globally available suspending vehicle (SyrSpend SF PH4 liquid): caffeine 10.0 mg/mL, carvedilol 1.0 mg/mL, clomipramine hydrochloride 5.0 mg/mL, folic acid 1.0 mg/mL, hydrochlorothiazide 5.0 mg/mL, loperamide hydrochloride 1.0 mg/mL, methotrexate 2.5 mg/mL, nadolol 10.0 mg/mL, naltrexone hydrochloride 1.0 mg/mL and pentoxifylline 20.0 mg/mL, stored at both controlled refrigerated (2-8°C) and room (20-25°C) temperature.

Methods

Compatibility was assessed by measuring the per cent recovery at different time points throughout a 90-day period. Quantification of the APIs was performed by high performance liquid chromatography (HPLC-UV) using a stability-indicating method.

Results

Methods were adequately validated. Forced degradation studies showed that at least one parameter influenced the stability of the APIs. All suspensions were assayed and showed API contents of between 90% and 110% over 90 days.

Discussion

Given the percentage of recovery of the APIs within the suspensions, the expiration date of the final products (API+vehicle) was found to be at least 90 days for all suspensions, for both controlled refrigerated and room temperature.

Conclusions

The results suggest that SyrSpend SF PH4 liquid is a stable suspending vehicle for compounding APIs from different pharmacological classes.

Product Substitution as a Way Forward in Avoiding Potentially Harmful Excipients in Neonates

OBJECTIVES

Our objectives were to explore the possibility of avoiding neonatal exposure to potentially harmful excipients of interest (EOI)-parabens, polysorbate 80, propylene glycol, benzoates, saccharin sodium, sorbitol and ethanol-through product substitution in Europe.

METHODS

We performed a 3-day service evaluation survey and a 1-day point prevalence study in 20 and 21 European countries, respectively. Analysis included active pharmaceutical ingredients (APIs) used in ≥10 % of units. We calculated the potential reduction in number of products with EOI through substitution in three stages: (1) similar API and route of administration, (2) plus similar dosage form and (3) plus similar strength. The reduction of individual exposure was analysed according to the second-stage criteria.

RESULTS

We identified 137 products for 25 APIs that contained EOI. Substitution with EOI-free product(s) was available for 88 % (n = 120), 66 % (n = 91) and 31 % (n = 42) of products according to the first-, second- and third-stage criteria, respectively. Overall, 456 (63 % of 726) neonates received products containing EOI. Substitution of the products that had alternatives with similar API and dosage form would reduce the number of exposed neonates from 456 to 257 (44 % reduction).

CONCLUSIONS

EOI-free formulations are available for a substantial number of products currently used in European neonates. Replacement of only the most frequently used products may spare almost half of neonates from unnecessary exposure to EOI.

Intensive dialysis and pregnancy

Pregnancy in women with end stage renal disease on renal replacement therapy is uncommon due to the physiologic changes associated with renal failure as well as the complexities and risk involved in managing these patients. As most of these women had long periods of illness with chronic kidney disease, the effects of their chronic illness together with the current societal trends to delay child bearing to a more advanced maternal age can hamper fertility. For those able to conceive, intensified hemodialysis (HD), through longer and/or more frequent dialysis sessions, offers improved maternal and neonatal outcomes. Intensified HD is most conveniently offered in the patient's home, where possible. This review expands the scope of the Implementing Hemodialysis in the Home website and associated supplement published previously in Hemodialysis International and includes information tailored to women of reproductive age. We describe the necessary counseling that women should receive before conception and before intensification of HD, and provide a detailed management strategy that includes nephrologic and obstetric care, should pregnancy occur.

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

Paediatric patients, particularly preterm neonates, present many pharmacological challenges. Due to the difficulty in conducting clinical trials in these populations dosing information is often extrapolated from adult populations. As the processes of absorption, distribution, metabolism and excretion of drugs change throughout growth and development extrapolation presents risk of over or underestimating the doses required. Information about the development these processes, particularly drug metabolism pathways, is still limited with weight based dose adjustment presenting the best method of estimating pharmacokinetic changes due to growth and development. New innovations in pharmacokinetic research, such as population pharmacokinetic modelling, present unique opportunities to conduct clinical trials in these populations improving the safety and effectiveness of the drugs used. More research is required into this area to ensure the best outcomes for our most vulnerable patients.

Drug-induced acid-base disorders

The incidence of acid-base disorders (ABDs) is high, especially in hospitalized patients. ABDs are often indicators for severe systemic disorders. In everyday clinical practice, analysis of ABDs must be performed in a standardized manner. Highly sensitive diagnostic tools to distinguish the various ABDs include the anion gap and the serum osmolar gap. Drug-induced ABDs can be classified into five different categories in terms of their pathophysiology: (1) metabolic acidosis caused by acid overload, which may occur through accumulation of acids by endogenous (e.g., lactic acidosis by biguanides, propofol-related syndrome) or exogenous (e.g., glycol-dependant drugs, such as diazepam or salicylates) mechanisms or by decreased renal acid excretion (e.g., distal renal tubular acidosis by amphotericin B, nonsteroidal anti-inflammatory drugs, vitamin D); (2) base loss: proximal renal tubular acidosis by drugs (e.g., ifosfamide, aminoglycosides, carbonic anhydrase inhibitors, antiretrovirals, oxaliplatin or cisplatin) in the context of Fanconi syndrome; (3) alkalosis resulting from acid and/or chloride loss by renal (e.g., diuretics, penicillins, aminoglycosides) or extrarenal (e.g., laxative drugs) mechanisms; (4) exogenous bicarbonate loads: milk-alkali syndrome, overshoot alkalosis after bicarbonate therapy or citrate administration; and (5) respiratory acidosis or alkalosis resulting from drug-induced depression of the respiratory center or neuromuscular impairment (e.g., anesthetics, sedatives) or hyperventilation (e.g., salicylates, epinephrine, nicotine).

Potentially harmful excipients in neonatal medicines: a pan-European observational study

OBJECTIVES

We aimed to describe administration of eight potentially harmful excipients of interest (EOI)-parabens, polysorbate 80, propylene glycol, benzoates, saccharin sodium, sorbitol, ethanol and benzalkonium chloride-to hospitalised neonates in Europe and to identify risk factors for exposure.

METHODS

All medicines administered to neonates during 1 day with individual prescription and demographic data were registered in a web-based point prevalence study. Excipients were identified from the Summaries of Product Characteristics. Determinants of EOI administration (geographical region, gestational age (GA), active pharmaceutical ingredient, unit level and hospital teaching status) were identified using multivariable logistical regression analysis.

RESULTS

Overall 89 neonatal units from 21 countries participated. Altogether 2095 prescriptions for 530 products administered to 726 neonates were recorded. EOI were found in 638 (31%) prescriptions and were administered to 456 (63%) neonates through a relatively small number of products (n=142; 27%). Parabens, found in 71 (13%) products administered to 313 (43%) neonates, were used most frequently. EOI administration varied by geographical region, GA and route of administration. Geographical region remained a significant determinant of the use of parabens, polysorbate 80, propylene glycol and saccharin sodium after adjustment for the potential covariates including anatomical therapeutic chemical class of the active ingredient.

CONCLUSIONS

European neonates receive a number of potentially harmful pharmaceutical excipients. Regional differences in EOI administration suggest that EOI-free products are available and provide the potential for substitution to avoid side effects of some excipients.

Development and Validation of an HPLC-UV Assay to Quantify Plasma Levels of Sulfametrol: A Preferential Antibiotic in Children

BACKGROUND

Sulfonamides in combination with trimethoprim are frequently used antibiotics. They work synergistic. In infections with Pneumocystis jiroveci or Stenotrophomonas maltophilia, higher dosages are indicated than in other infections. Therapeutic drug monitoring (TDM) is warranted to assure the efficacy while limiting toxicity. Although trimethoprim in combination with sulfamethoxazole is the most common combination with established TDM target concentrations, the intravenous formulation is not suited for children because of its additives ethanol and propylene glycol to increase solubility. An alternative can be sulfametrol in combination with trimethoprim. When sulfametrol was introduced in the hospital, there was a need for a TDM method for sulfametrol.

METHODS

A High Pressure Liquid Chromatography-Ultraviolet (HPLC-UV) detection method for sulfametrol determination in plasma was developed and validated according to the International Conference on Harmonization guidelines. Linearity, limit of detection, lower limit of quantification, recovery, process efficiency, selectivity, within-run precision, between-run precision, and sample stability were tested.

RESULTS

All tested parameters met the required criteria. For linearity, r was 0.9948, lower limit of quantification was 10 mg/L, and limit of detection was 6 mg/L. Recovery was 100.4% and process efficiency 94.4%. Selectivity was met with no interfering peaks at the retention time of 4.2 minutes. Between-run precision and within-run precision were evaluated by replicating quality control levels, resulting in a within-run relative average standard deviation of 0.8% and a between-run relative standard deviation of 2.3%. Recovery of the samples after storing 8 days was 101.9% and recovery of already tested vials was 98.8% after 48 hours.

CONCLUSIONS

In conclusion, an HPLC-UV method for sulfametrol determination in human plasma was developed and validated. The method is fast, accurate, reproducible, and has a short analysis time. It is now being used in routine TDM in our clinic.

Propylene glycol toxicity in children

Propylene glycol (PG) is a commonly used solvent for oral, intravenous, and topical pharmaceutical agents. Although PG is generally considered safe, when used in high doses or for prolonged periods, PG toxicity can occur. Reported adverse effects from PG include central nervous system (CNS) toxicity, hyperosmolarity, hemolysis, cardiac arrhythmia, seizures, agitation, and lactic acidosis. Patients at risk for toxicity include infants, those with renal or hepatic insuficiency, epilepsy, and burn patients receiving extensive dermal applications of PG containing products. Laboratory monitoring of PG levels, osmolarity, lactate, pyruvate, bicarbonate, creatinine, and anion gap can assist practitioners in making the diagnosis of PG toxicity. Numerous studies and case reports have been published on PG toxicity in adults. However, very few have been reported in pediatric patient populations. A review of the literature is presented.

Pain management in newborns

As a standard of care for preterm/term newborns effective pain management may improve their clinical and neurodevelopmental outcomes. Neonatal pain is assessed using context-specific, validated, and objective pain methods, despite the limitations of currently available tools. Therapeutic approaches reducing invasive procedures and using pharmacologic, behavioral, or environmental measures are used to manage neonatal pain. Nonpharmacologic approaches like kangaroo care, facilitated tucking, non-nutritive sucking, sucrose, and others can be used for procedural pain or adjunctive therapy. Local/topical anesthetics, opioids, NSAIDs/acetaminophen and other sedative/anesthetic agents can be incorporated into NICU protocols for managing moderate/severe pain or distress in all newborns.

An observational study of blood concentrations and kinetics of methyl- and propyl-parabens in neonates

PURPOSE

Systemic exposure to parabens in the neonatal population, in particular propyl-parabens (PPB), remains a concern. Blood concentrations and kinetics of methyl-parabens (MPB) and PPB were therefore determined in neonates receiving medicines containing these excipients.

METHODS

A multi-centre, non-interventional, observational study of excipient-kinetics in neonates. 'Dried Blood Spot' samples were collected opportunistically at the same time as routine samples and the observations modelled using a non-linear mixed effects approach.

RESULTS

A total of 841 blood MPB and PPB concentration data were available for evaluation from 181 pre- and term-neonates. Quantifiable blood concentrations of MPB and PPB were observed in 99% and 49% of patients, and 55% and 25% of all concentrations were above limit of detection (10 ng/ml), respectively. Only MPB data was amenable to modelling. Oral bioavailability was influenced by type of formulation and disposition was best described by a two compartment model with clearance (CL) influenced by post natal age (PNA); CL PNA<21 days 0.57 versus CL PNA>21 days 0.88 L/h.

CONCLUSIONS

Daily repeated administration of parabens containing medicines can result in prolonged systemic exposure to the parent compound in neonates. Animal toxicology studies of PPB that specifically address the neonatal period are required before a permitted daily exposure for this age group can be established.

Pediatric drug formulations: a review of challenges and progress

Children differ from adults in many aspects of pharmacotherapy, including capabilities for drug administration, medicine-related toxicity, and taste preferences. It is essential that pediatric medicines are formulated to best suit a child's age, size, physiologic condition, and treatment requirements. To ensure adequate treatment of all children, different routes of administration, dosage forms, and strengths may be required. Many existing formulations are not suitable for children, which often leads to off-label and unlicensed use of adult medicines. New regulations, additional funding opportunities, and innovative collaborative research initiatives have resulted in some recent progress in the development of pediatric formulations. These advances include a paradigm shift toward oral solid formulations and a focus on novel preparations, including flexible, dispersible, and multiparticulate oral solid dosage forms. Such developments have enabled greater dose flexibility, easier administration, and better acceptance of drug formulations in children. However, new pediatric formulations address only a small part of all therapeutic needs in children; moreover, they are not always available. Five key issues need to be addressed to stimulate the further development of better medicines for children: (1) the continued prioritization of unmet formulation needs, particularly drug delivery in neonates and treatment gaps in pediatric cancers and childhood diseases in developing countries; (2) a better use of existing data to facilitate pediatric formulation development; (3) innovative technologies in adults that can be used to develop new pediatric formulations; (4) clinical feedback and practice-based evidence on the impact of novel formulations; and (5) improved access to new pediatric formulations.

Remifentanil for endotracheal intubation in premature infants: A randomized controlled trial

Objective:

Endotracheal intubation is a common procedure in neonatal care. The objective of this study was to determine whether the premedication with remifentanil before intubation has analgesic effects in newborn infants.

Methods:

A total of 40 premature infants who needed endotracheal intubation for intubation-surfactant-extubation method were randomly assigned in two groups of an equal number at two university hospitals. The control group was given 10 μg/kg atropine IV infusions in 1 min and then 2 ml normal saline. In the case group, the atropine was given with the same method and then remifentanil was administered 2 μg/kg IV infusions in 2 min.

Findings:

For remifentanil and control groups, the mean birth weight were 1761 ± 64 and 1447 ± 63 grams (P = 0.29), and the mean gestational ages were 31.69 ± 3.5 and 30.56 ± 2.8 weeks (P = 0.28), respectively. Using premature infant pain profile score, infants who received remifentanil felt significantly less pain than the control group (15.1 ± 1.6 vs. 7.5 ± 1.4; P < 0.001). There were no significant differences in the duration of endotracheal intubation procedure (20.8 ± 6 vs. 22.8 ± 7.3 s; P = 0.33), the number of attempts for successful intubation and oxygen desaturation between groups.

Conclusion:

Premedication with remifentanil has good analgesic effects for endotracheal intubation in premature infants without significant derangements in mean blood pressure and oxygen saturation.

Toxic excipients in medications for neonates in Brazil

The aim was to describe the exposure to excipients among neonates hospitalised in the neonatal intensive care unit (NICU) of a public hospital in Brasilia, Brazil. This was a retrospective study based on medicines that were prescribed electronically to neonates (≤28 days) who were admitted to the NICU of a hospital in Brasilia between January 1 and March 31, 2012. Excipients were identified from the medicine package leaflets and were classified according to toxicity. Seventy-nine infants received a total of 1,303 prescriptions comprising 77 formulations and 70 active drugs. Eighty-six excipients were identified, of which, 9 were harmful excipients (HE) and 48 were potentially harmful excipients (PHE). Almost all the neonates (98.7 %) were exposed to at least one HE and PHE. Preterm neonates (n = 64; 1,502 neonate days) presented high risk of exposure to polysorbate 80 (3.26/100 neonate days), sodium hydroxide (3.39), PG (3.19) and propylparaben (3.06). Full-term neonates (n = 15; 289 neonate days) presented risks in relation to phenol (4.84), ethanol (3.8) and sodium citrate (3.46).

CONCLUSION

Neonates in NICUs in Brazil are exposed to a wide variety of HE and PHE with unpredictable results. Safer alternatives are needed, as well as further studies on the subject.

Risk assessment of neonatal excipient exposure: lessons from food safety and other areas

Newborn babies can require significant amounts of medication containing excipients intended to improve the drug formulation. Most medicines given to neonates have been developed for adults or older children and contain excipients thought to be safe in these age groups. Many excipients have been used widely in neonates without obvious adverse effects. Some excipients may be toxic in high amounts in which case they need careful risk assessment. Alternatively, it is conceivable that ill-founded fears about excipients mean that potentially useful medicines are not made available to newborn babies. Choices about excipient exposure can occur at several stages throughout the lifecycle of a medicine, from product development through to clinical use. Making these choices requires a scalable approach to analysing the overall risk. In this contribution we examine these issues.

A report from the pediatric formulations task force: perspectives on the state of child-friendly oral dosage forms

Despite the fact that a significant percentage of the population is unable to swallow tablets and capsules, these dosage forms continue to be the default standard. These oral formulations fail many patients, especially children, because of large tablet or capsule size, poor palatability, and lack of correct dosage strength. The clinical result is often lack of adherence and therapeutic failure. The American Association of Pharmaceutical Scientists formed a Pediatric Formulations Task Force, consisting of members with various areas of expertise including pediatrics, formulation development, clinical pharmacology, and regulatory science, in order to identify pediatric, manufacturing, and regulatory issues and areas of needed research and regulatory guidance. Dosage form and palatability standards for all pediatric ages, relative bioavailability requirements, and small batch manufacturing capabilities and creation of a viable economic model were identified as particular needs. This assessment is considered an important first step for a task force seeking creative approaches to providing more appropriate oral formulations for children.

The STEP (Safety and Toxicity of Excipients for Paediatrics) database: part 2 - the pilot version

The screening and careful selection of excipients is a critical step in paediatric formulation development as certain excipients acceptable in adult formulations, may not be appropriate for paediatric use. While there is extensive toxicity data that could help in better understanding and highlighting the gaps in toxicity studies, the data are often scattered around the information sources and saddled with incompatible data types and formats. This paper is the second in a series that presents the update on the Safety and Toxicity of Excipients for Paediatrics ("STEP") database being developed by Eu-US PFIs, and describes the architecture data fields and functions of the database. The STEP database is a user designed resource that compiles the safety and toxicity data of excipients that is scattered over various sources and presents it in one freely accessible source. Currently, in the pilot database data from over 2000 references/10 excipients presenting preclinical, clinical, regulatory information and toxicological reviews, with references and source links. The STEP database allows searching "FOR" excipients and "BY" excipients. This dual nature of the STEP database, in which toxicity and safety information can be searched in both directions, makes it unique from existing sources. If the pilot is successful, the aim is to increase the number of excipients in the existing database so that a database large enough to be of practical research use will be available. It is anticipated that this source will prove to be a useful platform for data management and data exchange of excipient safety information.

[Off-label use of drugs in pediatric emergencies: limitations and grey areas of drug approval]

In the medical treatment of children drugs are frequently used outside the boundaries of the approved licensing and use under the terms of off-label use is possible. However, this requires critical reasoning and experience with the drug involved. With help of a traffic light colored spreadsheet this article illustrates the limitations, problems and possibilities of pharmacotherapy in pediatric emergencies or pediatric anesthesia. Of the 45 emergency drugs listed in this article most can be used in childhood, at least under specific conditions. Licensing restrictions occur especially in the newborn period and infancy resulting in frequent off-label use. Severe pitfalls, such as the propofol infusion syndrome after long-term sedation with propofol under the age of 16 years, emphasize the need for serious reflection on the substances involved. Decisions regarding pharmaceutical therapy should be based on the current standard of medical knowledge. When official recommendations from pharmaceutical companies are missing, treatment decisions for off-label use can be based on guidelines, study and literature databases or recommendations in medical journals.

Developmental pharmacokinetics of propylene glycol in preterm and term neonates

AIM

Propylene glycol (PG) is often applied as an excipient in drug formulations. As these formulations may also be used in neonates, the aim of this study was to characterize the pharmacokinetics of propylene glycol, co-administered intravenously with paracetamol (800 mg PG/1000 mg paracetamol) or phenobarbital (700 mg PG/200 mg phenobarbital) in preterm and term neonates.

METHODS

A population pharmacokinetic analysis was performed based on 372 PG plasma concentrations from 62 (pre)term neonates (birth weight (bBW) 630-3980 g, postnatal age (PNA) 1-30 days) using NONMEM 6.2. The model was subsequently used to simulate PG exposure upon administration of paracetamol or phenobarbital in neonates (gestational age 24-40 weeks).

RESULTS

In a one compartment model, birth weight and PNA were both identified as covariates for PG clearance using an allometric function (CL(i) = 0.0849 × {(bBW/2720)(1.69) × (PNA/3)(0.201)}). Volume of distribution scaled allometrically with current bodyweight (V(i) = 0.967 × {(BW/2720)(1.45)}) and was estimated 1.77 times higher when co-administered with phenobarbital compared with paracetamol. By introducing these covariates a large part of the interindividual variability on clearance (65%) as well as on volume of distribution (53%) was explained. The final model shows that for commonly used dosing regimens, the population mean PG peak and trough concentrations range between 33-144 and 28-218 mg l(-1) (peak) and 19-109 and 6-112 mg l(-1) (trough) for paracetamol and phenobarbital formulations, respectively, depending on birth weight and age of the neonates.

CONCLUSION

A pharmacokinetic model was developed for PG co-administered with paracetamol or phenobarbital in neonates. As such, large variability in PG exposure may be expected in neonates which is dependent on birth weight and PNA.

Educational paper: formulation-related issues in pediatric clinical pharmacology

Developmental physiological changes occur throughout childhood, with important changes observed within the first few weeks and months from birth, potentially affecting drug pharmacokinetics. The impact of confounding factors in relation to the availability of clinically relevant and adequate drug formulations and administration devices is underestimated. Hence, it is important to highlight presently the relevance of formulation issues. Since 2007, the EU Paediatric Regulation enforces paediatric investigation plans in which the applicant has to justify the clinical relevance of each dosage form proposed in relation to age subsets involved and the suitability of administration modalities. Therefore, pediatric drug development has become more relevant, and the importance of using age-appropriate drug formulations has been acknowledged by investigators and other stakeholders. Palatability and acceptability assessment is considered to be important by the regulatory bodies as well as excipient safety and tolerability, as it can be an issue particularly in very young children. However, there remains a lack of research into pediatric biopharmaceutics (methodological input regarding in vitro tools and bridging studies). Clinical pharmacologists with expertise ranging from pharmacodynamics, pharmacokinetics, adverse drug effects, and toxicology should actively contribute in advancing drug formulation issues in children.