Sensory stimulations potentializing digital therapeutics pain control.

For the past two decades, using Digital Therapeutics (DTx) to counter painful symptoms has emerged as a novel pain relief strategy. Several studies report that DTx significantly diminish pain while compensating for the limitations of pharmacological analgesics (e.g., addiction, side effects). Virtual reality (VR) is a major component of the most effective DTx for pain reduction. Notably, various stimuli (e.g., auditory, visual) appear to be frequently associated with VR in DTx. This review aims to compare the hypoalgesic power of specific stimuli with or without a VR environment. First, this review will briefly describe VR technology and known elements related to its hypoalgesic effect. Second, it will non-exhaustively list various stimuli known to have a hypoalgesic effect on pain independent of the immersive environment. Finally, this review will focus on studies that investigate a possible potentialized effect on pain reduction of these stimuli in a VR environment.

Pain Reduction With an Immersive Digital Therapeutic in Women Living With Endometriosis-Related Pelvic Pain: At-Home Self-Administered Randomized Controlled Trial.

BACKGROUND: The management of chronic pelvic pain in women with endometriosis is complex and includes the long-term use of opioids. Patients not fully responsive to drugs or ineligible for surgical treatments need efficient alternatives to improve their quality of life and avoid long-term sequelae. OBJECTIVE: This randomized controlled trial aimed to assess the effects of repeated at-home administrations of a 20-minute virtual reality (VR) solution (Endocare) compared with a sham condition on pain in women experiencing pelvic pain due to endometriosis. METHODS: Patients were instructed to use the VR headsets twice daily for at least 2 days and for up to 5 days starting on their first day of painful periods. Pain perception was measured using a numerical scale (0-10) before and 60, 120, and 180 minutes after each treatment administration. General pain, stress, fatigue, medication intake, and quality of life were reported daily by patients. RESULTS: A total of 102 patients with endometriosis were included in the final analysis (Endocare group: n=51, 50%; sham group: n=51, 50%). The mean age was 32.88 years (SD 6.96) and the mean pain intensity before treatment was 6.53 (SD 1.74) and 6.22 (SD 1.69) for the Endocare group and the sham control group, respectively (P=.48). Pain intensity decreased in both groups from day 1 to day 5 along with a decrease in medication use. Maximum pain intensity reduction of 51.58% (SD 35.33) occurred at day 2, 120 minutes after treatment for the Endocare group and of 27.37% (SD 27.23) at day 3, 180 minutes after treatment for the control group. Endocare was significantly superior to the sham on day 1 (120 minutes, P=.04; 180 minutes, P=.001), day 2 (0 minutes, P=.02; 60, 120, and 180 minutes, all P<.001), and day 3 (60 minutes, P=.01; 120 minutes, P=.005; 180 minutes, P=.001). Similarly, the mean perceived pain relief was significantly higher with Endocare on day 1 (120 and 180 minutes P=.004 and P=.001, respectively) and day 2 (60, 120, and 180 minutes P=.003, P=.004, and P=.007, respectively) compared to the control. No adverse event was reported. CONCLUSIONS: This study confirmed the effectiveness and safety of self-repeated administrations of a VR immersive treatment used at home while reducing overall pain medication intake in women diagnosed with endometriosis experiencing moderate-to-severe pelvic pain. TRIAL REGISTRATION: ClinicalTrials.gov NCT05172492; https://clinicaltrials.gov/ct2/show/NCT05172492.

Atrial Fibrillation Detection With an Analog Smartwatch: Prospective Clinical Study and Algorithm Validation.

BACKGROUND: Atrial fibrillation affects approximately 4% of the world's population and is one of the major causes of stroke, heart failure, sudden death, and cardiovascular morbidity. It can be difficult to diagnose when asymptomatic or in the paroxysmal stage, and its natural history is not well understood. New wearables and connected devices offer an opportunity to improve on this situation. OBJECTIVE: We aimed to validate an algorithm for the automatic detection of atrial fibrillation from a single-lead electrocardiogram taken with a smartwatch. METHODS: Eligible patients were recruited from 4 sites in Paris, France. Electrocardiograms (12-lead reference and single lead) were captured simultaneously. The electrocardiograms were reviewed by independent, blinded board-certified cardiologists. The sensitivity and specificity of the algorithm to detect atrial fibrillation and normal sinus rhythm were calculated. The quality of single-lead electrocardiograms (visibility and polarity of waves, interval durations, heart rate) was assessed in comparison with the gold standard (12-lead electrocardiogram). RESULTS: A total of 262 patients (atrial fibrillation: n=100, age: mean 74.3 years, SD 12.3; normal sinus rhythm: n=113, age: 61.8 years, SD 14.3; other arrhythmia: n=45, 66.9 years, SD 15.2; unreadable electrocardiograms: n=4) were included in the final analysis; 6.9% (18/262) were classified as Noise by the algorithm. Excluding other arrhythmias and Noise, the sensitivity for atrial fibrillation detection was 0.963 (95% CI lower bound 0.894), and the specificity was 1.000 (95% CI lower bound 0.967). Visibility and polarity accuracies were similar (1-lead electrocardiogram: P waves: 96.9%, QRS complexes: 99.2%, T waves: 91.2%; 12-lead electrocardiogram: P waves: 100%, QRS complexes: 98.8%, T waves: 99.5%). P-wave visibility accuracy was 99% (99/100) for patients with atrial fibrillation and 95.7% (155/162) for patients with normal sinus rhythm, other arrhythmias, and unreadable electrocardiograms. The absolute values of the mean differences in PR duration and QRS width were <3 ms, and more than 97% were <40 ms. The mean difference between the heart rates from the 1-lead electrocardiogram calculated by the algorithm and those calculated by cardiologists was 0.55 bpm. CONCLUSIONS: The algorithm demonstrated great diagnostic performance for atrial fibrillation detection. The smartwatch's single-lead electrocardiogram also demonstrated good quality for physician use in daily routine care. TRIAL REGISTRATION: ClinicalTrials.gov NCT04351386; http://clinicaltrials.gov/ct2/show/NCT04351386.

Paediatric clinical research in Europe: an insight on experts' needs and perspectives.

PedCRIN is a Horizon 2020 project aimed to develop a paediatric component of ECRIN (European Clinical Research Infrastructure Network) including tools supporting the conduct of neonatal and paediatric trials. A structured, cross-sectional, closed-ended questionnaire was electronically administered from April to May 2017 to stakeholders involved in paediatric clinical research to capture their needs to receive infrastructural support to cover specific research gaps. The questionnaire included 6 headings and 29 subheadings. Each item was evaluated using a Likert-scale. 147 questionnaires were returned (response rate of 24.6%). The application of innovative study design and the preparation of protocols for paediatric interventional clinical trials had the highest frequency of high need for support (123 and 117 respondents, respectively). Similarly, the identification and applications to relevant calls for funding was acknowledged as an area in which support is needed (123 respondents declaring high need). In 14 out of 29 activities, need for support was significantly higher in the respondents not being part of a Paediatric Research Network or Consortium (especially for regulatory expertise, pharmacovigilance and GCP training). Conclusions: These results document that the achievement of PedCRIN objectives would greatly advantage the paediatric research community.

Informed consent for neonatal trials: practical points to consider and a check list.

Obtaining informed consent from parents of critically ill neonates can be challenging. The parental decision-making process is influenced by the severity of the child's condition, the benefit-risk balance, their emotional state and the quality of the relationship with the clinical team. Independent of local legislation, parents may prefer that consent is sought from both. Misconceptions about the absence of risks or unrealistic expectations about benefits should be openly addressed to avoid misunderstandings which may harm the relationship with the clinical team. Continuous consent can be sought where it is unclear whether the free choice of parental consent has been compromised. Obtaining informed consent is a dynamic process building on trusting relationships. It should include open and honest discussions about benefits and risks. Investigators may benefit from training in effective communication. Finally, involving parents in neonatal research including the development of the informed consent form and the process of obtaining consent should be considered standard practice.

Transethnic, Genome-Wide Analysis Reveals Immune-Related Risk Alleles and Phenotypic Correlates in Pediatric Steroid-Sensitive Nephrotic Syndrome.

Background Steroid-sensitive nephrotic syndrome (SSNS) is a childhood disease with unclear pathophysiology and genetic architecture. We investigated the genomic basis of SSNS in children recruited in Europe and the biopsy-based North American NEPTUNE cohort.Methods We performed three ancestry-matched, genome-wide association studies (GWAS) in 273 children with NS (Children Cohort Nephrosis and Virus [NEPHROVIR] cohort: 132 European, 56 African, and 85 Maghrebian) followed by independent replication in 112 European children, transethnic meta-analysis, and conditional analysis. GWAS alleles were used to perform glomerular cis-expression quantitative trait loci studies in 39 children in the NEPTUNE cohort and epidemiologic studies in GWAS and NEPTUNE (97 children) cohorts.Results Transethnic meta-analysis identified one SSNS-associated single-nucleotide polymorphism (SNP) rs1063348 in the 3' untranslated region of HLA-DQB1 (P=9.3×10-23). Conditional analysis identified two additional independent risk alleles upstream of HLA-DRB1 (rs28366266, P=3.7×10-11) and in the 3' untranslated region of BTNL2 (rs9348883, P=9.4×10-7) within introns of HCG23 and LOC101929163 These three risk alleles were independent of the risk haplotype DRB1*07:01-DQA1*02:01-DQB1*02:02 identified in European patients. Increased burden of risk alleles across independent loci was associated with higher odds of SSNS. Increased burden of risk alleles across independent loci was associated with higher odds of SSNS, with younger age of onset across all cohorts, and with increased odds of complete remission across histologies in NEPTUNE children. rs1063348 associated with decreased glomerular expression of HLA-DRB1, HLA-DRB5, and HLA-DQB1.Conclusions Transethnic GWAS empowered discovery of three independent risk SNPs for pediatric SSNS. Characterization of these SNPs provide an entry for understanding immune dysregulation in NS and introducing a genomically defined classification.

Clinical trials in neonates: How to optimise informed consent and decision making? A European Delphi survey of parent representatives and clinicians.

OBJECTIVES: Parental consent for the participation of their neonate in neonatal research is influenced by the quality of the information delivered and the interaction between parents and investigators. Failure to provide important information may lead to difficulties in the decision making process of parents. This Delphi survey aims to establish a consensus between parent representatives of neonatal associations and healthcare professionals concerning the information deemed essential by both parties in order to improve the recruitment of neonates into clinical trials. METHOD: This study was conducted in Europe among parent representatives and healthcare professionals. In this 3-phase study, 96 items were defined by the Scientific Committee (CS), composed of 11 clinicians (from 8 countries) and 1 parent representative of the European network of neonatal associations. Then the Committee of Experts (CE) composed of 16 clinicians were matched by country with 16 national parent representatives and evaluated these items in two rounds. The importance of each item was evaluated by each member of the CE on a scale between 1 and 9 based on their personal experience. RESULTS: Fifty eight items reached the second and final level of consensus. In contrast to clinicians, parent representatives preferred to be informed about the study by the physician in charge of their child. They also favoured additional support during the informed consent process and stated that both parents need to agree and sign. CONCLUSION: The set of 58 items on which parents and clinicians reached consensus will be helpful to healthcare professionals seeking parental consent for the inclusion of a neonate in a clinical trial. Providing parents with information about the trial by the investigator in the presence of the patient's neonatologist, developing closer contacts with parents and informing them of the available support by parents associations may be helpful for parents.

Capacities and Competences for Drug Evaluation in European Neonatal Intensive Care Units: A Survey and Key Issues for Improvement.

BACKGROUND: Multicenter neonatal clinical trials aim to provide evidence-based drug evaluation, but recruiting neonates requires collaboration, standard procedures, and trained neonatologists. METHODS: A questionnaire based on a previous Delphi study was sent to European neonatal intensive care units (NICUs) to collect their research experience and identify areas for improvement. RESULTS: Of 247 NICUs,79 (32%) responded: 69 were level III units and 10 were level II units. In level III centers, 62% had medical staff dedicated to research and 65% conducted regular in-house audits. Similarities were observed in the median number of trials per year (level II: 2; level III: 5), Good Clinical Practice training (level II: 78%; level III: 66%), and standard operating procedures (level II: 63%; level III: 71%). Most NICUs had access to scientific advice for trial design, conduct, data management, and regulatory aspects. Involvement of patient advocacy groups was more common in level II units (level II: 75%; level III: 59%). A "quality" score of 34 "quality" research items was calculated for all centers (mean: 23.2 ± 6.2; range: 6-34). CONCLUSION: Research experience and processes vary across Europe. Harmonizing research practices and setting standards will allow building a European neonatal network for effective, safe, and quality neonatal drug development.

Principles and applications of pharmacometrics in drug evaluation in children.

Drug evaluation in children is difficult for many well-identified reasons and many drugs are still used off-label. Innovative approaches are particularly adapted to the paediatric and neonatal populations, as clinical trials are difficult to conduct, need adapted designs in order to define the optimal dosage regimen in many diseases and therapeutic areas. Population approaches to define pharmacokinetics and pharmacokinetic/pharmacodynamics are now more currently used to define dosing regimens, adapted to the different paediatric and neonatal age groups, that allow to increase efficacy and reduce toxicity, by taking into account factors explaining variability in drug response. Such approaches are presented and the evaluation of vancomycin in neonates is detailed as different steps allowed validation of the optimal strategy to administer vancomycin in neonates.

Drug evaluation in children 10years after the European pediatric regulation current challenges and perspectives.

The European pediatric regulation, that entered into force in June 2007 with the objectives to improve the health of children in Europe, dramatically changed the regulatory environment of paediatric drug evaluation in Europe. The recent 10years European medicines agency (EMA) report showed that the number of paediatric trials increased and that 238 new medicines and indications for use in children were authorised in the EU. However, results remain constrated and futur developments require european collaborations beween all experts in developmental pharmacology, drug evaluation and trial conduct, training, all aspects already considered in different EU paediatric programs.

Pharmacogenetics of post-transplant diabetes mellitus in children with renal transplantation treated with tacrolimus.

BACKGROUND: Post-transplant diabetes mellitus (PTDM) is a major complication of immunosuppressive therapy, with many risk factors reported in adults with renal transplantation. The objective of this study was to investigate potential non-genetic and genetic risk factors of PTDM in children with renal transplantation treated with tacrolimus. METHODS: A national database was screened for patients developing PTDM within 4 years following tacrolimus introduction. PTDM was defined as glucose disorder requiring anti-diabetic treatment. PTDM patients were matched to "non-PTDM" control transplanted children according to age, gender, and duration of post-transplant follow-up. Patients were genotyped for six selected genetic variants in POR*28 (rs1057868), PPARa (rs4253728), CYP3A5 (rs776746), VDR (rs2228570 and rs731236), and ABCB1 (rs1045642) genes, implicated in glucose homeostasis and tacrolimus disposition. RESULTS: Among the 98 children with renal transplantation enrolled in this multicentre study, 18 developed PTDM. None of the clinical and biological parameters was significant between PTDM and control patients. Homozygous carriers of POR*28 or wild-type ABCB1 (rs1045642) gene variants were more frequent in PTDM than in control patients with differences close to significance (p = 0.114 and p = 0.066 respectively). A genetic score based on these variants demonstrated that POR*28/*28 and ABCB1 CC or CT genotype carriers were at a significantly higher risk of developing PTDM after renal transplantation. CONCLUSION: Identification of PTDM risk factors should allow clinicians to allocate the best immunosuppressant for each patient with renal transplantation, and improve care for patients who are at a higher risk.

mRNA expression of drug metabolism enzymes and transporter genes at birth using human umbilical cord blood.

Growth and maturation changes are mainly responsible for differences in drug pharmacokinetics and pharmacodynamics observed between adults and children, especially neonates. Ontogeny of drug-metabolizing enzymes and transporters plays an important role in drugs interindividual pharmacokinetic variability but data are limited in both term and preterm neonates. This study aimed to characterize mRNA expression of the main drug-metabolizing enzymes and transport proteins involved in drug disposition, using umbilical cord blood (UCB), according to gender, gestational age, and genetic background. A large panel of genes was quantified as follows: cytochrome P450 system (n = 12), UGT family (n = 6), TPMT and transporters (n = 3), in 56 samples of UCB of twin neonates. Gene expression was measured using real-time reverse transcription polymerase chain reaction with 18S rRNA as the endogenous control for normalization of data. Relative expression of the samples was expressed using the 2-ΔΔCt method for comparison of gene expression levels. Twenty genes were expressed in UCB at birth with variable levels of expression and tissue-specific gene expression when compared to data on the fetal liver. Gestational age, gender, and genetic background influenced the expression of the genes tested. Easily accessible UCB samples will enable further studies to evaluate the influence of covariates. This suggests that these covariates need to be considered when assessing substrate drugs disposition mediated by these metabolizing enzymes and transporters in the neonatal population.

Sequential analysis in neonatal research-systematic review.

As more new drugs are discovered, traditional designs come at their limits. Ten years after the adoption of the European Paediatric Regulation, we performed a systematic review on the US National Library of Medicine and Excerpta Medica database of sequential trials involving newborns. Out of 326 identified scientific reports, 21 trials were included. They enrolled 2832 patients, of whom 2099 were analyzed: the median number of neonates included per trial was 48 (IQR 22-87), median gestational age was 28.7 (IQR 27.9-30.9) weeks. Eighteen trials used sequential techniques to determine sample size, while 3 used continual reassessment methods for dose-finding. In 16 studies reporting sufficient data, the sequential design allowed to non-significantly reduce the number of enrolled neonates by a median of 24 (31%) patients (IQR - 4.75 to 136.5, p = 0.0674) with respect to a traditional trial. When the number of neonates finally included in the analysis was considered, the difference became significant: 35 (57%) patients (IQR 10 to 136.5, p = 0.0033). CONCLUSION: Sequential trial designs have not been frequently used in Neonatology. They might potentially be able to reduce the number of patients in drug trials, although this is not always the case. What is known: • In evaluating rare diseases in fragile populations, traditional designs come at their limits. About 20% of pediatric trials are discontinued, mainly because of recruitment problems. What is new: • Sequential trials involving newborns were infrequently used and only a few (n = 21) are available for analysis. • The sequential design allowed to non-significantly reduce the number of enrolled neonates by a median of 24 (31%) patients (IQR - 4.75 to 136.5, p = 0.0674).

An optimal LC-MS/MS method for determination of azithromycin in white blood cells: application to pediatric samples.

BACKGROUND: Studies suggest that particular antimicrobial and anti-inflammatory properties of azithromycin (AZM) can be related to its extensive accumulation in white blood cells (WBCs). However, available methods for determination of AZM in WBCs require large blood volumes unsuited to a pediatric context. Therefore, an LC-MS/MS method was developed for determination of AZM in WBCs. RESULTS: WBCs were isolated from 500 µl of whole blood by lysing red blood cells. Then, lysis of WBCs was performed with methanol/buffer containing AZM-d3-(13)C as internal standard. After reversed phase LC, detection was performed under multiple reaction monitoring conditions in positive electrospray mode. Linearity ranged from 0.5 to 200 ng per WBC sample. Within-run and overall accuracy and precision ranged from 95.3 to 101.1% and from 1.6 to 4.7%, respectively. All validation parameters fulfilled international requirements. CONCLUSIONS: This method can be easily performed on small samples and provides reliable data, including in children and neonates.

A Delphi process to optimize quality and performance of drug evaluation in neonates.

BACKGROUND: Neonatal trials remain difficult to conduct for several reasons: in particular the need for study sites to have an existing infrastructure in place, with trained investigators and validated quality procedures to ensure good clinical, laboratory practices and a respect for high ethical standards. The objective of this work was to identify the major criteria considered necessary for selecting neonatal intensive care units that are able to perform drug evaluations competently. METHODOLOGY AND MAIN FINDINGS: This Delphi process was conducted with an international multidisciplinary panel of 25 experts from 13 countries, selected to be part of two committees (a scientific committee and an expert committee), in order to validate criteria required to perform drug evaluation in neonates. Eighty six items were initially selected and classified under 7 headings: "NICUs description-Level of care" (21), "Ability to perform drug trials: NICU organization and processes (15), "Research Experience" (12), "Scientific competencies and area of expertise" (8), "Quality Management" (16), "Training and educational capacity" (8) and "Public involvement" (6). Sixty-one items were retained and headings were rearranged after the first round, 34 were selected after the second round. A third round was required to validate 13 additional items. The final set includes 47 items divided under 5 headings. CONCLUSION: A set of 47 relevant criteria will help to NICUs that want to implement, conduct or participate in drug trials within a neonatal network identify important issues to be aware of. SUMMARY POINTS: 1) Neonatal trials remain difficult to conduct for several reasons: in particular the need for study sites to have an existing infrastructure in place, with trained investigators and validated quality procedures to ensure good clinical, laboratory practices and a respect for high ethical standards. 2) The present Delphi study was conducted with an international multidisciplinary panel of 25 experts from 13 countries and aims to identify the major criteria considered necessary for selecting neonatal intensive care units (NICUs) that are able to perform drug evaluations competently. 3) Of the 86 items initially selected and classified under 7 headings--"NICUs description-Level of care" (21), "Ability to perform drug trials: NICU organization and processes (15), "Research Experience" (12), "Scientific competencies and area of expertise" (8), "Quality Management" (16), "Training and educational capacity" (8) and "Public involvement" (6)--47 items were selected following a three rounds Delphi process. 4) The present consensus will help NICUs to implement, conduct or participate in drug trials within a neonatal network.

Ureaplasma, bronchopulmonary dysplasia, and azithromycin in European neonatal intensive care units: a survey.

A survey was set up to gauge the opinions of neonatologists on the role of Ureaplasma in bronchopulmonary dysplasia (BPD) development, the use of azithromycin for BPD prevention, and the factors influencing azithromycin use in European neonatal intensive care units (NICUs). 167 NICUs participated in the survey, representing 28 European countries. For respondents, the two major perceived risk factors for BPD were prematurity of <28 weeks and high oxygen requirements. Only 38% of NICUs had a protocol for BPD prevention and 47% routinely tested for Ureaplasma. In cases of infection, macrolides were the first choice. Most (78%) NICUs were interested in participating in a trial evaluating azithromycin safety and efficacy in reducing BPD rates. Opinions and clinical practice varied between European neonatal units, and differences in Ureaplasma treatment and prevention of BPD highlight the need for further azithromycin evaluation and for improved therapeutic knowledge in preterms.

Physiopathology of idiopathic nephrotic syndrome: lessons from glucocorticoids and epigenetic perspectives.

Idiopathic nephrotic syndrome (INS) has been studied for decades in attempt to understand the physiopathological mechanisms explaining the disease. It is recognized as a multifactorial disease, with immunological components targeting kidney functions. Many hypotheses have been discussed or tested, including the role of a circulating factor, polymorphisms of genes implicated in lymphocyte maturation and differentiation, and DNA epigenetic modifications. In the present review, the data supporting these different (and probably combinatorial) hypotheses have been reviewed in order to identify and discuss the possible pathways implicated in the physiopathology of INS.

Pharmacogenetics and individualized therapy in children: immunosuppressants, antidepressants, anticancer and anti-inflammatory drugs.

Pharmacogenetic polymorphisms that change the amino acid sequences in coding regions only account for part of the interindividual differences in disease susceptibility and drug response. Additional pharmacogenomic and epigenetic factors are also involved. In children, pharmacogenetic studies are limited, although it has been clear for many years that the interactions between developmental patterns of drug-metabolizing enzymes and transporters have a major impact on dose exposure with age-specific dosage requirements. This article will analyze the factors affecting variability in drug response in children and focus on the pharmacogenetic polymorphisms of immunosuppressants, antidepressants, anticancer and anti-inflammatory drugs. Additional pharmacogenetic and epigenetic studies should be performed to allow the individualization of therapy in children.

Population pharmacokinetics and Bayesian estimator of mycophenolic acid in children with idiopathic nephrotic syndrome.

AIMS: To develop a population pharmacokinetic model for mycophenolic acid (MPA) in children with idiopathic nephrotic syndrome (INS) treated with mycophenolate mofetil (MMF), identify covariates that explain variability and determine the Bayesian estimator of the area under the concentration-time curve over 12 h (AUC(0-12)). METHODS: The pharmacokinetic model of MMF was described from 23 patients aged 7.4 +/- 3.9 years (range 2.9-14.9) using nonlinear mixed-effects modelling (NONMEM) software. A two-compartment model with lag-time and first-order absorption and elimination was developed. The final model was validated using visual predictive check. Bayesian estimator was validated using circular permutation method. RESULTS: The population pharmacokinetic parameters were apparent oral clearance 9.7 l h(-1), apparent central volume of distribution 22.3 l, apparent peripheral volume of distribution 250 l, inter-compartment clearance 18.8 l h(-1), absorption rate constant 5.16 h(-1), lag time 0.215 h. The covariate analysis identified body weight and serum albumin as individual factors influencing the apparent oral clearance. Accurate Bayesian estimation of AUC(0-12) was obtained using the combination of three MPA concentrations measured just before (T(0)), 1 and 4 h (T(1) and T(4)) after drug intake with a small error of 0.298 microg h(-1) ml(-1) between estimated and reference AUC(0-12). CONCLUSIONS: The population pharmacokinetic model of MPA was developed in children with INS. A three-point (T(0), T(1) and T(4)h) Bayesian estimator of AUC(0-12) was developed and might be used to investigate the relation between MPA pharmacokinetic and pharmacodynamics in children with INS and determine if there is any indication to monitor MPA exposure in order to improve patient outcome based on individual AUC-controlled MMF dosing.

mRNA expression of MDR1 and major metabolising enzymes in human fetal tissues.

Metabolising enzymes and transport proteins are largely expressed in human tissues. They have major impact on drug disposition and effects. We studied mRNA expression of phase I and II metabolising enzymes and transporters in fetal tissues at different development stages. Hepatic, duodenal, renal and neurological fetal tissues were studied at 15, 27 and 42 weeks gestation and mRNA expression of 84 enzymes and transporters was analysed by with the RT(2) Profiler PCR array system. There was wide variability in gene expression between different samples. Independently from age, the highest expression levels were observed in the liver and the lowest in the brain for the majority of genes tested. There was significant increase in gene expression with age in duodenal and hepatic tissues.