Population pharmacokinetics of olanzapine in pediatric patients with psychiatric disorders.

OBJECTIVE: To develop and validate a population pharmacokinetic (PPK) model of oral olanzapine in pediatric Chinese patients in order to individualize therapy in this population. METHODS: A total of 897 serum concentrations from 269 pediatric patients taking oral olanzapine (ages 8 to 17 years) were collected. Demographic parameters, biological characteristics and concomitant medications were investigated as covariates. The data was analyzed using a nonlinear mixed-effects modeling approach. Bootstrapping (1000 runs), normalized prediction distribution error (NPDE), and external validation of 62 patients were employed. Simulations were performed to explore the individualized dosing regimens in various situations. RESULTS: The one-compartment model with first-order absorption and elimination had an apparent clearance (CL/F) of 10.38 L/h, a distribution volume (V/F) of 9.41 L/kg and an absorption rate constant (Ka) fixed at 0.3 h-1. The equation was CL∕F (L∕h) = 10.38 × (body weight∕60)0.25 ×1.33 (if male) × 0.71 (if co-occurrence of infection) × 0.51 (if co-therapy with fluvoxamine) × 1.27 (if co-therapy with sertraline) × 1.43 (if co-therapy with valproate). The final model had satisfactory stability, robustness, and predictive ability. The results from a simulation suggested the oral olanzapine doses required for male and female pediatric patients weighing between 40-60 kg without co-medication were 10-15 mg/day and 7.5-10 mg/day, respectively, and dosage adjustments should be based on sex and body weight; and co-administrated with valproate, sertraline, or fluvoxamine. CONCLUSION: This model may help individualize optimum dosing of oral olanzapine for pediatric patients.

Ziprasidone population pharmacokinetics and co-medication effects in Chinese patients.

Ziprasidone is widely used in the treatment of psychiatric disorders. Despite its prevalence, there is a notable lack of population pharmacokinetics (PPK) studies on ziprasidone in serum, both domestically and internationally. This study aimed to comprehensively investigate the various factors influencing the PPK characteristics of Ziprasidone, thereby providing a scientific basis for personalized treatment strategies in clinical settings. This is a retrospective study. A non-linear mixed-effects modeling method was used for data analysis, with the ziprasidone PPK model established using the Phoenix NLME 8.1 software. Model evaluation employed goodness-of-fit plots, visual predictive checks, and Bootstrap methods to ensure reliability and accuracy. To further validate the model's applicability, data from an additional 30 patients meeting the same inclusion criteria but not included in the final model were collected for external validation. Simulations were performed to explore the personalized dosage regimens. This retrospective analysis collected 547 drug concentration data points from 185 psychiatric disorder patients, along with related medical records. The data included detailed demographic information (such as age, gender, weight), dosing regimens, laboratory test results, and concomitant medication details. In the final model, Ka was fixed at 0.5 h-1 based on literature, and the population typical values for ziprasidone clearance (CL) and volume of distribution (V) were 18.74 L/h and 110.24 L, respectively. Co-administration of lorazepam and valproic acid significantly influenced the clearance of ziprasidone. Moreover, the model evaluation indicated good stability and predictive accuracy. A simple to use dosage regimen table was derived based on the results of simulations. This study successfully established and validated a PPK model for ziprasidone in Chinese patients with psychiatric disorders. The model provides a scientific reference for individualized dosing of ziprasidone and holds the potential to optimize treatment strategies, thereby enhancing therapeutic efficacy and safety.

A Chinese medicine called Danggui Longhui may be a new clinically relevant clozapine inducer: Two case reports identified by therapeutic drug monitoring.

BACKGROUND: Danggui Longhui is a traditional Chinese medicine made from the dried root of Angelica sinensis. It is used in psychiatric patients in China to reduce associated constipation. In a population pharmacokinetic model in olanzapine patients from Beijing Anding Hospital, we demonstrate that dangguilonghui tablets doubled olanzapine clearance, indicating the induction of olanzapine metabolism. Olanzapine metabolism is similar to clozapine metabolism. METHODS: Two cases of possible clozapine induction using dangguilonghui tablets 4 g/day were identified in Beijing Anding Hospital. Dividing the minimum therapeutic concentration of 350 ng/mL by the concentration-to-dose (C/D) ratio provides the minimum therapeutic dose. RESULTS: Case 1 was a female smoker on clozapine for 415 days. The mean of 6 clozapine C/D ratios associated with smoking provided a minimum therapeutic dose of 267 mg/day. There were 6 steady-state concentrations on the combination of valproic acid and dangguilonghui tablets, which provided a much higher minimum therapeutic dose of 833 mg/day. Four steady-state clozapine C/D ratios based on smoking and valproate after 4 months of carbamazepine 200 mg/day provided a minimum therapeutic dose of 603 mg/day. Case 2 was a female non-smoker on clozapine for 58 days. She had 3 clozapine C/D ratios on dangguilonghui tablets with a mean of 0.30 ng/mL providing a minimum therapeutic dose of 1167 mg/day. CONCLUSION: Future clinical studies with repeated measures need to replicate the possibility that dangguilonghui tablets are a moderate-to-strong inducer of clozapine metabolism as suggested by these two limited cases.

Population pharmacokinetics of Amisulpride in Chinese patients with schizophrenia with external validation: the impact of renal function.

Introduction: Amisulpride is primarily eliminated via the kidneys. Given the clear influence of renal clearance on plasma concentration, we aimed to explicitly examine the impact of renal function on amisulpride pharmacokinetics (PK) via population PK modelling and Monte Carlo simulations. Method: Plasma concentrations from 921 patients (776 in development and 145 in validation) were utilized. Results: Amisulpride PK could be described by a one-compartment model with linear elimination where estimated glomerular filtration rate, eGFR, had a significant influence on clearance. All PK parameters (estimate, RSE%) were precisely estimated: apparent volume of distribution (645 L, 18%), apparent clearance (60.5 L/h, 2%), absorption rate constant (0.106 h-1, 12%) and coefficient of renal function on clearance (0.817, 10%). No other significant covariate was found. The predictive performance of the model was externally validated. Covariate analysis showed an inverse relationship between eGFR and exposure, where subjects with eGFR= 30 mL/min/1.73 m2 had more than 2-fold increase in AUC, trough and peak concentration. Simulation results further illustrated that, given a dose of 800 mg, plasma concentrations of all patients with renal impairment would exceed 640 ng/mL. Discussion: Our work demonstrated the importance of renal function in amisulpride dose adjustment and provided a quantitative framework to guide individualized dosing for Chinese patients with schizophrenia.

Which can Predict the Outcome of Antidepressants: Metabolic Genes or Pharmacodynamic Genes?

Drug therapy is the primary modality for depression; however, its outcome is often unpredictable, ranging from beneficial effects to serious adverse effects. Genetic variations in drug metabolizing enzymes and pharmacodynamic molecules are responsible for a considerable proportion of interindividual differences in the effectiveness and toxicity of antidepressants. For the improvement in the use of antidepressants, the focus is mainly on personalized treatment emphasizing interindividual differences in genes. This study provides a comprehensive review of the literature on the clinical applications of pharmacogenomics for antidepressant therapy. The polymorphisms of metabolizing enzymes (CYP2D6, CYP2C19, and others) governing the pharmacokinetic behavior of drugs are potential predictors of side effects or treatment failure with medications and there are good pharmacogenetic clinical recommendations for a wide selection of psychopharmacological agents based on functional diplotypes of CYP2C19 and CYP2D6. The relationship between pharmacodynamic genes, including FKBP5, SLC6A4, BDNF, ABCB1, HTR1A, and HTR2A, and clinical outcomes varies in different races. Receptors that are currently used as drug targets for antidepressant drugs are evolutionarily conserved to a higher extent than genes encoding drug metabolism, and the actionability of pharmacodynamic-related genotyping is currently still questionable. The limited availability of largescale, long-term clinical studies on different races and medications currently impedes the implementation of pharmacogenomics in antidepressant treatment. The use of pharmacokinetic and pharmacodynamic modeling, and therapeutic drug monitoring combined with genetic, somatic, dietary, and environmental factors represents a promising avenue for improving the precision and effectiveness of antidepressant therapy.

A brief history of clozapine in China with a look forward.

Clozapine was first manufactured in China in 1976. Clozapine is currently used not only for treatment-refractory schizophrenia (TRS), but also continues to be used in the treatment of patients with non-TRS and other mental disorders; moreover, low-dose clozapine is also used in sedative-hypnotic therapy and in combination with other drugs. There is need for studies in China using various titrations and assessing their risk for myocarditis and aspiration pneumonia. The Chinese clozapine package insert will also greatly benefit from these changes.

Published population pharmacokinetic models of valproic acid in adult patients: a systematic review and external validation in a Chinese sample of inpatients with bipolar disorder.

BACKGROUND: This study reviewed all published valproic acid (VPA) population pharmacokinetic (PPK) models in adult patients and assessed them using external validation methods to determine predictive performance. METHODS: Thirteen published PPK models (labeled with letters A to M) not restricted to children were identified in PubMed, Embase, and Web of Science databases. They were evaluated in a sample totaling 411 serum concentrations from 146 adult inpatients diagnosed with bipolar disorder in a Chinese hospital. Serum concentrations of VPA were analyzed by validated ultra-performance liquid chromatography-tandem mass spectrometry. Performance was assessed by four tests (prediction-based diagnostics, visual predictive checks, normalized prediction distribution error, and Bayesian forecasting). RESULTS: Models K and L, developed in large samples of Chinese and Thai patients, showed good performance in our Chinese dataset. Models H and J demonstrated good performance in 2 and 3 of the 4 tests, respectively. Another seven models exhibited intermediate performance. The models with the worst performance, F and M, could not be improved by Bayesian forecasting. CONCLUSION: In our validation study, the most important factors contributing to good performance were absence of children, Asian ethnicity, one-compartment models, and inclusion of body weight and VPA dose in previously published models.

Population pharmacokinetics of valproic acid in adult Chinese patients with bipolar disorder.

PURPOSE: To develop and validate a population pharmacokinetic (PPK) model of valproic acid (VPA) in adult Chinese patients with bipolar disorder, and provide guidance for individualized therapy in this population. METHODS: A total of 1104 serum concentrations from 272 patients were collected in this study. The data analysis was performed using a nonlinear mixed-effects modeling approach. Covariates included demographic parameters, biological characteristics, and concomitant medications. Bootstrap validation (1000 runs), normalized prediction distribution error (NPDE), and external validation of 50 patients were employed to evaluate the final model. RESULTS: A one-compartment model with first-order absorption and elimination was developed for VPA extended-release tablets. VPA clearance was significantly influenced by three variables: sex (12% higher in male patients), daily dose (increasing with the 0.13 exponent), and body weight (increasing with the 0.56 exponent). Typical values for the absorption rate constant (Ka), apparent clearance (CL/F), and apparent distribution volume (V/F) for a female patient weighing 70 kg administered VPA 1000 mg/day were 0.18 h-1, 0.46 L/h, and 12.84 L, respectively. The results of model evaluation indicated a good stable and precise performance of the final model. CONCLUSIONS: A qualified PPK model of VPA was developed in Chinese patients with bipolar disorder. This model could be used as a suitable tool for the personalization of VPA dosing for bipolar patients.

Population pharmacokinetics and dose simulation of cyclosporine in Chinese children with nephrotic syndrome: Effects of weight and total cholesterol.

OBJECTIVE: The existing cyclosporine (CsA) population pharmacokinetic (PPK) model does not apply well to children. The aim of the study was to establish a CsA PPK model for Chinese children with nephrotic syndrome (NS) and conduct a dosage simulation to provide drug-dosing guidance. MATERIALS AND METHODS: A total of 311 drug monitoring data points were collected from 165 children. Blood samples were collected before dosing. Non-linear mixed-effects model was applied to develop the PPK model. Covariate analysis was applied to select candidate factors associated with pharmacokinetic (PK) parameters. A model-based simulation was then performed to estimate the optimal initial dose for different patient subgroups. RESULTS: A one-compartment model with first-order absorption and elimination was chosen to describe the drug trajectory in vivo. The typical values for apparent clearance/absorption fraction (CL/F) and apparent volume of distribution/absorption fraction (V/F) were 40.1/h and 2.32 ×103L, respectively. The covariate analysis revealed that weight and total cholesterol were strongly associated with CL/F and V/F. Goodness-of-fit and model evaluation suggested that the proposed model was acceptable. A dosage regimen table was created for specific pediatric groups to facilitate clinical application. CONCLUSION: A PPK model of CsA in Chinese pediatrics was successfully established, allowing the development of individualized dosing regimens for Chinese pediatric NS patients.

A Machine Learning Model to Predict Risperidone Active Moiety Concentration Based on Initial Therapeutic Drug Monitoring.

Risperidone is an efficacious second-generation antipsychotic (SGA) to treat a wide spectrum of psychiatric diseases, whereas its active moiety (risperidone and 9-hydroxyrisperidone) concentration without a therapeutic reference range may increase the risk of adverse drug reactions. We aimed to establish a prediction model of risperidone active moiety concentration in the next therapeutic drug monitoring (TDM) based on the initial TDM information using machine learning methods. A total of 983 patients treated with risperidone between May 2017 and May 2018 in Beijing Anding Hospital were collected as the data set. Sixteen predictors (the initial TDM value, dosage, age, WBC, PLT, BUN, weight, BMI, prolactin, ALT, MECT, Cr, AST, Ccr, TDM interval, and RBC) were screened from 26 variables through univariate analysis (p < 0.05) and XGBoost (importance score >0). Ten algorithms (XGBoost, LightGBM, CatBoost, AdaBoost, Random Forest, support vector machine, lasso regression, ridge regression, linear regression, and k-nearest neighbor) compared the model performance, and ultimately, XGBoost was chosen to establish the prediction model. A cohort of 210 patients treated with risperidone between March 1, 2019, and May 31, 2019, in Beijing Anding Hospital was used to validate the model. Finally, the prediction model was evaluated, obtaining R 2 (0.512 in test cohort; 0.374 in validation cohort), MAE (10.97 in test cohort; 12.07 in validation cohort), MSE (198.55 in test cohort; 324.15 in validation cohort), RMSE (14.09 in test cohort; 18.00 in validation cohort), and accuracy of the predicted TDM within ±30% of the actual TDM (54.82% in test cohort; 60.95% in validation cohort). The prediction model has promising performance to facilitate rational risperidone regimen on an individualized level and provide reference for other antipsychotic drugs' risk prediction.

The Impact of Smoking, Sex, Infection, and Comedication Administration on Oral Olanzapine: A Population Pharmacokinetic Model in Chinese Psychiatric Patients.

BACKGROUND AND OBJECTIVE: Prior olanzapine population pharmacokinetic (PPK) models have focused on the effects of sex and smoking on olanzapine clearance. This PPK model in Chinese adult psychiatric patients also investigated the influence of comedications and co-occurrence of infections on olanzapine clearance, and explored how to personalize oral olanzapine dosage in the clinical setting. METHODS: A total of 1546 serum concentrations from 354 patients were collected in this study. A one-compartment model with first-order absorption was employed to develop the PPK model using a nonlinear mixed-effects modeling approach. Covariates included demographic parameters, co-occurrence of infection and concomitant medications (including dangguilonghui tablets, a Chinese herbal medicine for constipation). Bootstrap validation (1000 runs) and external validation of 50 patients were employed to evaluate the final model. Simulations were performed to explore the personalization of olanzapine dosing after stratification by sex, smoking, and comedication with valproate. RESULTS: Typical estimates for the absorption rate constant (Ka), apparent clearance (CL/F), and apparent distribution volume (V/F) were 0.30 h-1, 12.88 L/h, and 754.41 L, respectively. Olanzapine clearance was increased by the following variables: 1.23-fold by male sex, 1.23-fold by smoking, 1.23-fold by comedication with valproate, 1.16-fold by sertraline, and 2.01-fold by dangguilonghui tablets. Olanzapine clearance was decreased by the following variables: 0.75-fold by co-occurrence of infection, 0.70-fold by fluvoxamine, and 0.78-fold by perphenazine. The model evaluation indicated that the final model's performance was good, stable, and precise. CONCLUSION: This study contributes to the personalization of oral olanzapine dosing, but further studies should be performed to verify the effects of infection and comedications, including valproate and dangguilonghui.

This study included a total of 1546 serum olanzapine concentrations from 354 Chinese adult psychiatric patients that were analyzed by a complex mathematical model. The goal was to explore how oral olanzapine is eliminated from the body in Chinese psychiatric patients and how to personalize its dosing. Prior studies using similar complex mathematical models only studied the effects of sex and smoking on olanzapine elimination. This study also investigated the influence of co-occurrence of infection and comedications, including dangguilonghui tablets. This is a Chinese herbal medicine used to treat constipation, including constipation secondary to olanzapine treatment. Olanzapine elimination was increased by the following variables: 1.23-fold by male sex, 1.23-fold by smoking, 1.23-fold by comedication with valproate, 1.16-fold by sertraline, and 2.01-fold by dangguilonghui tablets. Olanzapine elimination was decreased by the following variables: 0.75-fold by co-occurrence of infection, 0.70-fold by fluvoxamine, and 0.78-fold by perphenazine. This study contributes to the improvement of oral olanzapine dosing personalization, but further studies are needed to verify the effects of infection and comedications, including valproate and dangguilonghui.

The first study in pediatric: Population pharmacokinetics of sirolimus and its application in Chinese children with immune cytopenia.

The narrow therapeutic index and large inter-individual variability in sirolimus pharmacokinetics (PK) make therapeutic drug monitoring (TDM) necessary. Factors responsible for PK variability are not well understood, and published PK studies do not include pediatric patients with immune cytopenia. The objective of this study was to characterize the PK of sirolimus in pediatric patients with immune cytopenia and to develop a population PK model in Chinese children and evaluate its utility for dose individualization. A total of 27 children with either acquired or congenital immune cytopenia aged 8.16 ± 3.60 years (range: 1-15 years) were included. TDM data for sirolimus were collected. The population PK model of sirolimus was described using the nonlinear mixed-effects modeling (Phoenix NLME 1.3 software) approach. Covariate analysis was applied to select candidate factors associated with PK parameters. The final model was validated using bootstrap (1000 runs) and visual predictive check (VPC) method. A one-compartment model with first-order absorption and elimination was developed. The outcome parameters were as follows: apparent clearance (CL/F) 5.63 L/h, apparent distribution volume (V/F) 144.16 L. Inter-individual variabilities for CL/F and V/F were 3.53% and 7.27%, respectively. The intra-individual variability of proportional error model was 22.45%. The covariate test found that body weight and total bilirubin were strongly associated with clearance; however, we did not find the relevance between the covariate and volume of distribution of sirolimus. Personalized dosage regimens were provided based on Bayesian method. The oral dose should be adjusted according to weight and total bilirubin. This is the first study to describe a population PK model of sirolimusin pediatric patients with immune cytopenia. Population pharmacokinetic (PPK) model-based dose individualization of sirolimus and the design of future clinical studies in children will be facilitated by the developed model in this study.

Safety and tolerability of a single dose T0001 in Chinese healthy adult volunteers: a first-in-human ascending dose study

T0001 is the first mutant of etanercept with a higher affinity to tumor necrosis factor α (TNF-α) than etanercept. In order to investigate the safety and tolerability of T0001, a study was carried out in healthy Chinese subjects. A first-in-human, dose escalation study was conducted in healthy Chinese subjects. Fifty-six subjects were divided into six dose cohorts (10 mg, 20 mg, 35 mg, 50 mg, 65 mg and 75 mg) to receive a single subcutaneous injection of T0001. Safety and tolerability assessment were based on the records of vital signs, physical examinations, clinical laboratory tests, 12-lead electrocardiograms and adverse events (AEs). All subjects were in good compliance and none withdraw due to AEs. No serious AEs occurred. A total of twenty-three AEs in sixteen subjects were recorded, and eighteen of these AEs were believed to be related to T0001. The most frequently reported AEs were injection site reactions and white blood cell count increase. All these AEs were of mild to moderate intensity and most of them recovered spontaneously within 14 days. In this study, no dose-limiting toxicity was observed, and the maximum tolerated dose was identified as 75 mg. T0001 was considered safe and generally well tolerated at doses up to 75 mg in healthy Chinese volunteers

Population pharmacokinetic study of delayed methotrexate excretion in children with acute lymphoblastic leukemia
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OBJECTIVE: To investigate the population pharmacokinetics of delayed methotrexate (MTX) excretion in children with acute lymphoblastic leukemia (ALL). MATERIALS AND METHODS: A total of 1,659 plasma concentration samples of MTX from 190 patients with 1 - 4 courses (plasma concentrations > 0.1 µmol/L) were collected in this study. The data analysis was performed using Phoenix NLME 1.3 software. The covariates included age, body surface area (BSA), body weight, alkaline phosphatase (ALP), aspartate aminotransferase (AST), alanine transaminase (ALT), total bilirubin (TBIL), and serum creatinine (SCr). The final model was validated by bootstrap resampling procedures (1,000 runs) and visual predictive check (VPC) method. RESULTS: The data were best described by a two-compartment linear pharmacokinetic model. The mean values of clearance (CL) and distribution volume (Vd) of MTX were 6.53 L/h and 67.88 L, respectively. Analysis of covariates showed that BSA influenced the CL of MTX. CONCLUSION: The final model was demonstrated as appropriate and effective for assessing the pharmacokinetic parameters of delayed MTX excretion in children with ALL.

Clozapine Metabolism in East Asians and Caucasians: A Pilot Exploration of the Prevalence of Poor Metabolizers and a Systematic Review.

PURPOSE/BACKGROUND: In clozapine therapeutic drug monitoring (TDM) studies, Chinese reached the same concentrations using half the dosage Caucasians use. Defining clozapine poor metabolizers (PMs) requires stratification by ethnicity, smoking, and sex. METHODS/PROCEDURES: After sex and smoking stratification in 129 Chinese inpatients (mean, 8.8 TDM samples per patient), we explored the association between the total concentration-dose (C/D) ratio and CYP1A2 (*1C, *1F, and *7) and CYP2C19 alleles (*2 and *3). A systematic literature review identified 22 clozapine TDM prior studies (13 in Caucasians and 7 in East Asians). FINDINGS/RESULTS: In our Chinese sample, the mean total clozapine C/D ratio (ng/mL per mg/d) was 1.96 for 22 male smokers, 2.07 for 5 female smokers, 2.47 for 36 male nonsmokers, and 2.95 for 66 female nonsmokers. CYP1A2 *1C had no significant effects, and CYP1A2 *1F had small effects. Five clozapine PMs (4%) needed low clozapine doses of 75 to 115 mg/d to get therapeutic concentrations. Using the same methodology in a published Italian sample, we found 5 PMs (3.3% of 152). In the systematic review, the clozapine C/D ratio (ng/mL per mg/d) was higher when comparing: (1) weighted mean values of 1.57 in 876 East Asians versus 1.07 in 1147 Caucasians and (2) ranks of 8 East Asians versus 13 Caucasian samples (P < 0.001). IMPLICATIONS/CONCLUSIONS: Future TDM studies need to further explore the frequency of clozapine PMs after sex and smoking stratification in East Asian and Caucasian patients. Compared with Caucasians, East Asians appear to have a clinically relevant decrease in clozapine clearance.

RhGLP-1 (7-36) protects diabetic rats against cerebral ischemia-reperfusion injury via up-regulating expression of Nrf2/HO-1 and increasing the activities of SOD.

The present study aimed to explore the neuroprotective effect and possible mechanisms of rhGLP-1 (7-36) against transient ischemia/reperfusion injuries induced by middle cerebral artery occlusion (MCAO) in type 2 diabetic rats. First, diabetic rats were established by a combination of a high-fat diet and low-dose streptozotocin (STZ) (30 mg/kg, intraperitoneally). Second, they were subjected to MCAO for 2 h, then treated with rhGLP-1 (7-36) (10, 20, 40 µg/kg i.p.) at the same time of reperfusion. In the following 3 days, they were injected with rhGLP-1 (7-36) at the same dose and route for three times each day. After 72 h, hypoglycemic effects were assessed by blood glucose changes, and neuroprotective effects were evaluated by neurological deficits, infarct volume and histomorphology. Mechanisms were investigated by detecting the distribution and expression of the nuclear factor erythroid-derived factor 2 related factor 2 (Nrf2) in ischemic brain tissue, the levels of phospho-PI3 kinase (PI3K)/PI3K ratio and heme-oxygenase-1 (HO-l), as well as the activities of superoxide dismutase (SOD) and the contents of malondialdehyde (MDA). Our results showed that rhGLP-1 (7-36) significantly reduced blood glucose and infarction volume, alleviated neurological deficits, enhanced the density of surviving neurons and vascular proliferation. The nuclear positive cells ratio and expression of Nrf2, the levels of P-PI3K/PI3K ratio and HO-l increased, the activities of SOD increased and the contents of MDA decreased. The current results indicated the protective effect of rhGLP-1 (7-36) in diabetic rats following MCAO/R that may be concerned with reducing blood glucose, up-regulating expression of Nrf2/HO-1 and increasing the activities of SOD.

Pharmacokinetics and immunogenicity of T0001, a newly developed anti-TNFα fusion protein, in healthy volunteers.

PURPOSE: T0001 was the first mutant of recombinant fusion protein of human tumor necrosis factor receptor and Fc fragment (rhTNFR:Fc) based on etanercept on a global scale. This study was carried out to investigate the pharmacokinetics (PK) and immunogenicity of T0001 in healthy Chinese volunteers. METHODS: This study was randomized, with a single ascending dose, and the first-in-human clinical trial of T0001. Healthy Chinese volunteers (n = 56; male: female = 1:1) were randomly assigned to receive a single subcutaneous (sc) injection of 10, 20, 35, 50, 65 or 75 mg of T0001. Blood samples were collected at designated time points after sc injection to assess immunogenicity and pharmacokinetics of T0001. RESULTS: During the study, no serious adverse events were observed. T0001 was slowly absorbed with a median Tmax of 84 h and slowly eliminated with a T1/2Z of 42.1-58.2 h. In the dose-exposure proportionality analysis, the estimated points for AUC0-∞ and Cmax were 0.87 with a 90% CI of 0.76-0.98 and 0.86 with a 90% CI of 0.74-0.97 respectively. The plasma concentration of free (unbound T0001) plasma TNFα and total (bound and unbound T0001) TNFα both increased significantly after the injection of T0001. Ten out of 56 volunteers (17.9%) tested positive for anti-drug antibodies (ADAs) at a low level. CONCLUSIONS: T0001 was safe and well-tolerated at doses up to 75 mg. Cmax and AUC0-∞ had an increasing tendency with dose levels, but we could not conclude that T0001 has linear PK properties in this study.

Population pharmacokinetics of lyophilized recombinant glucagon-like peptide-1 receptor agonist (recombinant exendin-4, rE-4) in Chinese patients with type 2 diabetes mellitus
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OBJECTIVE: To investigate the population pharmacokinetics of lyophilized recombinant glucagon-like peptide-1 receptor agonist (rE-4) in Chinese patients with type 2 diabetes mellitus (T2DM) for plasma concentration estimation and individualized treatment. METHODS: Twelve patients with T2DM were enrolled to receive subcutaneous injections of rE-4 at 5 µg twice daily for 84 days. Administration dosage was adjusted from 5 µg to 10 µg twice daily at day 29 in case of glycated albumin (GA) ≥ 17%. The population pharmacokinetic model was developed in the nonlinear mixed-effects modeling software NONMEM. RESULTS: The data were best described by a two-compartment model with first-order absorption and elimination. The outcome parameters were as follows: apparent clearance (CL/F) 6.67 L/h, apparent distribution volume of central compartment (Vc/F) 19.4 L, absorption rate constant (Ka) 1.39 h-1, apparent distribution volume of peripheral compartment (Vp/F) 22.6 L, intercompartmental clearance (Q/F) 1.28 L/h. The interindividual variabilities for CL/F, Vc/F, Ka, and Q/F were 64.4%, 57.7%, 45.5%, and 153.3%, respectively. The intra-individual variability of proportional error model was 41.7%. No covariate was screened out that showed significant influence on the model parameters. CONCLUSIONS: The established two-compartment model with first-order absorption and elimination successfully described the pharmacokinetic characteristics of rE-4 in Chinese patients with T2DM.
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