The study objective was to validate febuxostat dosage and administration in pediatric patients with hyperuricemia including gout, using an integrated population pharmacokinetic (PopPK) analysis in the Japanese population. Integrated PopPK analysis of febuxostat used a nonlinear mixed-effects modeling (NONMEM) program on plasma febuxostat concentration data for 2611 samples from Japanese pediatric patients with hyperuricemia including gout (n = 29) and from adult subjects who are healthy or have renal dysfunction (n = 113). We described febuxostat pharmacokinetics using an integrated PopPK model applicable both to pediatric patients and to the adult population.
View Article and Find Full Text PDFGiven the aging populations in advanced countries globally, many pharmaceutical companies have focused on developing central nervous system (CNS) drugs. However, due to the blood-brain barrier, drugs do not easily reach the target area in the brain. Although conventional screening methods for drug discovery involve the measurement of (unbound fraction of drug) brain-to-plasma partition coefficients, it is difficult to consider nonequilibrium between plasma and brain compound concentration-time profiles.
View Article and Find Full Text PDFRenal secretion plays an important role in excretion of drug from the kidney. Two major transporters known to be highly involved in renal secretion are MATE1/2 K and OCT2, the former of which is highly related to drug-drug interactions. Among published in silico models for MATE inhibitors, a previous model obtained a ROC-AUC value of 0.
View Article and Find Full Text PDFPredicting whether a compound can cause drug-induced liver injury (DILI) is difficult due to the complexity of drug mechanism. The cysteine trapping assay is a method for detecting reactive metabolites that bind to microsomes covalently. However, it is cumbersome to use 35S isotope-labeled cysteine for this assay.
View Article and Find Full Text PDFArtificial intelligence is expected to help identify excellent candidates in drug discovery. However, we face a lack of data, as it is time-consuming and expensive to acquire raw data perfectly for many compounds. Hence, we tried to develop a novel quantitative structure-activity relationship (QSAR) method to predict a parameter more precisely from an incomplete data set via optimizing data handling by making use of predicted explanatory variables.
View Article and Find Full Text PDFBackground: A micronucleus test is generally used to evaluate the genotoxic potential of chemicals. Exaggerated erythropoiesis, as occurs following bleeding, may induce an unexpected increase in micronucleus frequency. This false positive result would be typical in a genotoxicity study due to the enhanced progression of the cell cycle that restores decreased blood cells.
View Article and Find Full Text PDFBackground: The demand for physiologically based pharmacokinetic (PBPK) model is increasing currently. New drug application (NDA) of many compounds is submitted with PBPK models for efficient drug development. Tissue-to-plasma partition coefficient (K) is a key parameter for the PBPK model to describe differential equations.
View Article and Find Full Text PDFPharmacokinetic (PK) parameters such as clearance (CL) and volume of distribution (Vd) have been the subject of previous predictive models. However, having information of the concentration over time profile explicitly can provide additional value like time above MIC or AUC, etc., to understand both the efficacy and safety-related aspects of a compound.
View Article and Find Full Text PDFDrug absorption from the gastrointestinal tract is often restricted by efflux transport by P-glycoprotein (P-gp) and metabolism by CYP3A4. Both localize in the epithelial cells, and thus, their activities are directly affected by the intracellular drug concentration, which should be regulated by the ratio of permeability between apical (A) and basal (B) membranes. In this study, using Caco-2 cells with forced expression of CYP3A4, we assessed the transcellular permeation of A-to-B and B-to-A directions and the efflux from the preloaded cells to both sides of 12 representative P-gp or CYP3A4 substrate drugs and obtained the parameters for permeabilities, transport, metabolism, and unbound fraction in the enterocytes (f) using simultaneous and dynamic model analysis.
View Article and Find Full Text PDFBackground: Our previous research showed that uric acid lowering therapy (ULT) for gout and hyperuricemia is being prescribed for pediatric patients even though these drugs have not been approved for use in children. However, the actual clinical situation has not been clearly elucidated. In this paper, we provide an in-depth look at the details of actual clinical practice.
View Article and Find Full Text PDFThe importance of glucose is well known as an energy source in testes. In order to evaluate the effects of long-lasting hypoglycemia on testes, a novel glucokinase activator, TMG-123, was dosed to rats at 5, 20 and 100 mg/kg for 13 weeks. As a result, plasma glucose levels decreased for several hours with increasing doses over the dose range of 5 to 100 mg/kg.
View Article and Find Full Text PDFBackground: Although gout is rare in children, chronic sustained hyperuricemia can lead to monosodium urate deposits progressing to gout, just as in adults. This study assessed prevalence and characteristics of gout and asymptomatic hyperuricemia, and incidence of gouty arthritis in the pediatric population, using data from Japanese health insurance claims. The diagnosis and treatment of pediatric gout and hyperuricemia were analyzed, and specific characteristics of those patients were assessed.
View Article and Find Full Text PDFGlucose has an important role in spermatogenesis. Nevertheless there are few reports in which the effects of long-lasting hypoglycemia on male reproductive organs have been evaluated. Therefore, insulin was administered subcutaneously at 100, 200, and 400 IU/kg to male rats twice a day for one month.
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