Development and validation of a method for quantitation of cefepime/avibactam in M-H broth: application to antibacterial activity using in vitro PK/PD Model / 中国临床药理学与治疗学

AIM: To establish a method for quantitation of cefepime and avibactam in M-H broth, and applicated in the in vitro dynamic PK/PD model. METHODS: The cefepime was also determined using the high-performance liquid chromatography method (HPLC), the avibactam was also determined using the liquid chromatography-mass spectrometry (LC-MS/MS), an in vitro dynamic PK/PD model was established to study the PK/PD relationship of cefepime/avibactam against carbapenem resistant Klebsiella pneumoniae (CRKP). RESULTS: The linear ranges of cefepime and avibactam were good at (0.5-20) and (0.1-25) μg/mL (r=0.999), and the lower limit concentrations were 0.5 and 0.1 μg/mL. The extraction recoveries of cefepime and avibactam in M-H broth were 88.0%-101.7% and 90.9%-95.2%, the relative standard deviation of intra-day precision and inter-day precision were less than 5.2%. The concentration-time curves were well simulated by the PK/PD model. All observed concentrations in each experiment were in the range of 20% of the targeted values. For the CRKP of MIC=8 μg/mL and MIC=16 μg/mL, the colony decreased to 2.783Log10 CFU/mL and 1.325Log10 CFU/mL at the cefepime/avibactam 2.5 g q8 h administration after 24 h. CONCLUSION: The determination method of cefepime and avibactam in broth established in this study has high sensitivity and good stability. For the CRKP with MIC≤8 μg/mL,cefepime/avibactam showed that good anti-CRKP activity under routine administration in vitro dynamic PK/PD model.

PK/PD model of Chuanxiong gel plaster in treatment of rheumatoid arthritis / 中国中药杂志

In this experiment, the PK/PD fitting model of Chuanxiong(Chuanxiong Rhizoma) in the treatment of rheumatoid arthritis was established in the form of acupoint combined with external application gel paste. Firstly, the rheumatoid arthritis model was induced by ovalbumin, and the articular fluid of rabbits was extracted by microdialysis. The pharmacokinetic process of Chuanxiong in rabbit articular fluid was analyzed by UPLC-MS/MS, and the pharmacokinetic model was established. The pharmacodynamic effects of Chuanxiong on inflammatory factors IL-1β, TNF-α, and IL-6 were analyzed by enzyme-linked immunosorbent assay(ELISA). The pharmacodynamic model was established, and the PK/PD model was obtained by fitting the data of pharmacokinetics and pharmacodynamics. The results of pharmacokinetics showed that the concentration of ligustrolide A in the articular cavity by drug administration on classical acupoint Zusanli(ST 36) was higher than that by Yanglingquan(GB 34), which reflected the advantage of typical acupoint, while ligustrazine concentration was higher after administration through Yanglingquan than through Zusanli, which was different from the traditional acupoint theory. The results of pharmacodynamics showed that the drug had lag effect. The PK/PD model was constructed by fitting the data. When IL-1β was taken as the efficacy index, the PK/PD models of Chuanxiong in typical acupoint Zusanli group, atypical acupoint Yanglingquan group, and non-acupoint group were E=115.28C_e/(3 316.72+C_e), E=108.73C_e/(2 993.47+C_e), and E=101.34C_e/(3 028.51+C_e). When TNF-α was taken as the efficacy index, the PK/PD models of Chuanxiong in typical acupoint Zusanli group, atypical acupoint Yanglingquan group, and non-acupoint group were E=68.31C_e/(3 285.16+C_e), E=59.27C_e/(2 919.86+C_e), and E=53.61C_e/(2 862.87+C_e). When IL-6 was taken as the efficacy index, the PK/PD models of Chuanxiong in typical acupoint Zusanli group, atypical acupoint Yanglingquan group, and non-acupoint group were E=59.92C_e/(3 461.17+C_e), E=58.34C_e/(2 723.51+C_e), and E=49.17C_e/(2 862.76+C_e). The parameters showed that there were significant differences in E_(max), EC_(e50) and k_(eo). The analysis of data found that the PK/PD fitting effect of Zusanli, a typical acupoint, was the best, which proved that it was still the best site for drug administration. To sum up, it shows that there may be bidirectional selectivity between drugs and acupoints.

Advances in venlafaxine-related PK-PD relationship and influencing factors / 中国临床药理学与治疗学

Venlafaxine (VEN) is a new antidepressant drug that can effectively antagonize the reuptake of serotonin (5-HT) and norepinephrine (NE), compared with other antidepressants, venlafaxine pharmacokinetics / pharmacodynamics (PK-PD) is more regular and has the characteristics of less toxic side effects, fast oral absorption, and high bio-availability. This article reviews the PK-PD model-ling of venlafaxine and its quantitative relationship, as well as the factors affecting the process in vivo of venlafaxine, including sex, body weight, individual genotype, liver and kidney function impairment, drug-drug interaction and other related factors.

Eficácia in sílico do florfenicol no tratamento de pododermatite infecciosa por Fusobacterium necrophorum em ovelhas / In sílico efficacy of florfenicol in the treatment of Fusobacterium necrophorum infectious pododermatitis in sheep

Objetivou-se comparar o efeito in silico do florfenicol nas doses de 20 e 30 mg/Kg em ovinos pelas vias intravenosa (IV) e intramuscular (IM), usando a modelagem PK/PD. Realizou-se uma simulação de Monte Carlo com base nos dados de concentração plasmática de um estudo publicado anteriormente. Calculou-se a área sob a curva (ASC) e as taxas de eficácia do florfenicol para os efeitos bacteriostático, bactericida e de erradicação bacteriológica. A dose de 20 mg/Kg IV demonstrou efeitos de erradicação de 100, 93 e 0% para CIM de 0,5, 1 e acima, respectivamente. O efeito bacteriostático foi de 99 e 90% para CIM de 4 e 2 µg/ml, enquanto o bactericida foi de 14% para CIM de 2 µg/ml. A dose de 30 mg/Kg IV apresentou 100% de erradicação para CIM de 1 µg/mL e 100% de efeito bactericida para CIM de 2 µg/mL. Há 100% de efeito bacteriostático em CIM de 4 µg/ml. As doses de 20 e 30 mg/Kg IM mostraram 100% de erradicação para CIM até 1 µg/mL e 0% para CIM maiores. O efeito bacteriostático foi mantido em 100% para uma CIM de 4 µg/mL em ambas as doses. Este estudo mostra o efeito de erradicação bacteriológica do florfenicol nas doses de 20 e 30 mg/Kg, IV e IM. Recomenda-se que seja feito um estudo de eficácia in vivo com a dose de 30mg/Kg IM em ovinos infectados por F. necrophorum com MIC superior a 2 µg/mL.

We aimed to compare the in silico effect of florfenicol at doses of 20 and 30 mg/Kg in sheep by intravenous (IV) and intramuscular (IM) routes, using PK/PD modeling. We performed a Monte Carlo simulation based on plasma concentration data from a previously published study. We calculated the area under the curve (AUC) and the efficacy rates of florfenicol to bacteriostatic, bactericidal, and bacteriological eradication effects. The dose of 20 mg/Kg IV demonstrated 100, 93, and 0% eradication effects for MICs of 0.5, 1, and above, respectively. The bacteriostatic effect was 99 and 90% for MIC of 4 and 2 µg/ml, while the bactericide was 14% for MIC of 2 µg/ml. The 30 mg/Kg IV dose showed 100% eradication for MIC of 1 µg/mL and 100% bactericidal effect for MIC of 2 µg/mL. There is a 100% of bacteriostatic effect at MIC of 4 µg/ml. Doses of 20 and 30 mg/Kg IM showed 100% eradication for MIC up to 1 µg/mL and 0% for MIC above. The bacteriostatic effect was maintained at 100% for a MIC of 4 µg/mL at both doses. This study shows the bacteriological eradication effect of florfenicol at doses of 20 and 30 mg/Kg, IV, and IM. Therefore, we recommend an in vivo efficacy study with a dose of 30mg/Kg IM in sheep infected with F. necrophorum with MIC greater than two µg/mL.

The Journey and Excitement Following the Development of the First Peptide in a Pill: A Brief Overview of Pharmacology and Clinical Trials of Oral Semaglutide

Oral semaglutide is the newest discovery, the first in class peptide in a pill. Sodium N-(8-[2-hydroxybenzoyl]amino)caprylate (SNAC), a small fatty acid, has been co-formulated with semaglutide, which facilitates its absorption from the gastric mucosa. It has 94% homology with human glucagon-like peptide 1 (GLP-1). It comes in three dose forms – 3 mg, 7 mg and 14 mg. It is given as once daily dosing and is recommended in adult type 2 diabetes mellitus patients as monotherapy when metformin is contraindicated or not tolerated and in combination with other oral antidiabetic drugs (OADs). In a phase 3 trial, it has been shown to reduce glycated hemoglobin (HbA1c) up to 1.5%, with weight reduction up to 5 kg with a 14 mg dose. There was nonsignificant risk reduction of 21% in 3-point major adverse cardiovascular events (MACE) and 51% and 49% risk reduction in cardiovascular (CV) deaths and all-cause mortality, respectively. Oral semaglutide was found to be superior to empagliflozin, sitagliptin and liraglutide in both glycemic control and weight reduction. It also exhibits many pleiotropic effects – reduced energy intake, anti-inflammatory and anti-atherosclerotic effect, to name a few. Nausea was the most common side effect which was experienced by only 15% to 20% of patients. It was mild-to-moderate and transient. Overall, oral semaglutide has shown its efficacy both early and late in the management of diabetes, irrespective of renal and hepatic impairment.

Effects of extracorporeal membrane oxygenation on pharmacokinetics and pharmacodynamics of daptomycin in critically ill patients / 中国临床药理学与治疗学

AIM: To investigate the effect of extracorporeal membrane oxygenation (ECMO) on the pharmacokinetics/pharmacodynamics (PK/PD) of daptomycin in critically ill patients. METHODS: Twenty four patients with severe infection in our hospital were randomly selected and divided into ECMO group and non ECMO group. They were intravenously injected with daptomycin 500 mg qd. After the drug reached the stability statement, venous blood was collected at different time points before and after the infusion. The plasma drug concentration was measured and the pharmacokinetic parameters were calculated. The probability target acquisition (PTA) and the cumulative fraction response (CFR) were calculated by Monte Carlo simulation. RESULTS: After dosing, the main pharmacokinetic parameters in ECMO and non-ECMO group were calculated and listed as follows: C

The translational challenge in Chagas disease drug development

Chagas disease is a neglected tropical disease caused by the protozoan parasite Trypanosoma cruzi. There is an urgent need for safe, effective, and accessible new treatments since the currently approved drugs have serious limitations. Drug development for Chagas disease has historically been hampered by the complexity of the disease, critical knowledge gaps, and lack of coordinated R&D efforts. This review covers some of the translational challenges associated with the progression of new chemical entities from preclinical to clinical phases of development, and discusses how recent technological advances might allow the research community to answer key questions relevant to the disease and to overcome hurdles in R&D for Chagas disease.

Efetividade da infusão estendida de Piperacilina-tazobactana - Meropenem no tratamento de pacientes sépticos adultos queimados através da modelagem farmacocinética farmacodinâmica, PK/P / Meropenem and piperacillin/tazobactam by extended infusion and PK/PD approach for drug effectiveness

Introdução: Meropenem (MER) e Piperacilina/Tazobactana (PTZ) são agentes antimicrobianos largamente prescritos para pacientes grandes queimados internados em Unidade de Terapia Intensiva (UTI) com infecções nosocomiais causadas por Gram-negativos sensíveis CIM 2 mg/L, Enterobacteriaceae, EB e Non-enterobacteriaceae, NEB. A síndrome da resposta inflamatória sistêmica (SRIS) que ocorre durante o choque séptico no grande queimado pode causar alteração na farmacocinética do paciente em terapia intensiva, de modo que a dose recomendada pode não atingir o alvo desejado contra Gram-negativos de sensibilidade intermediária CIM >2 mg/L. Objetivo: Investigar a efetividade dos beta-lactâmicos piperacilina e meropenem na infusão estendida comparada à infusão intermitente recomendada, para os pacientes sépticos grandes queimados através da abordagem farmacocinética-farmacodinâmica (PK/PD). Ética, casuística e procedimentos: Autor e co-autores declararam não haver conflito de interesse. O protocolo foi aprovado, registro CAAE 07525118.3.0000.0068. No presente protocolo de estudo investigaram-se 36 pacientes sépticos grandes queimados, ambos os gêneros (12F/24M) em terapia intensiva do choque séptico com piperacilina-tazobactana 4,5g q6h ou meropenem 1g q8h. Os pacientes incluídos foram estratificados em dois grupos com base na administração através da infusão intermitente, 0,5 h (G1) ou da infusão estendida, 3 h (G2), ambos com 16 pacientes cada. Duas amostras sanguíneas (1,5mL/cada) foram coletadas no estado de equilíbrio (Steady State), 3ª e 5ª hora do início da infusão. Os níveis séricos de PTZ e MER foram mensurados através de cromatografia líquida, e a farmacocinética (PK) dos dois grupos de pacientes foi comparada aos dados reportados em voluntários sadios. A abordagem PK/PD foi aplicada para avaliação da cobertura do antimicrobiano a partir da estimativa do índice de predição de efetividade (% fΔT>CIM) e da probabilidade de alcançar o alvo terapêutico (PTA) com base no alvo PK/PD recomendado, 100%fΔT>CIM. Resultados e discussão: As características de admissão dos pacientes G1/G2 foram expressas através de mediana e interquartil: Clcr 115 (90-148) / 127 (90-170) ml/min; 30 (24-31) / 27 (24- 33,5) anos, 70 (61-75) / 71 (65-75) kg, 30 (20-42) / 33,9 (18-38,4)% área total de superfície queimada, SAPS3 53 (45-57) / 48 (37,8-59,5). Na admissão dos pacientes na UTI registrou-se G1/G2: trauma térmico (17/16), trauma elétrico (1/2), lesão inalatória (11/11), ventilação mecânica (16/9) e vasopressores foram necessários em 15/8 pacientes, G1/G2. Ocorreram diferentes alterações na farmacocinética dos dois beta-lactâmicos após a infusão estendida versus a infusão intermitente quando comparadas com dados relatados em voluntários sadios. Evidenciou-se prolongamento da meia vida decorrente do aumento do volume de distribuição. Estes resultados impactaram diferentemente a cobertura. O monitoramento de biomarcadores inflamatórios expressos em medianas (G1/G2) evidenciou aumento do PCR: 232/183mg/L e leucocitose (leucócitos 11/14 mil cel/mm3, neutrófilos 9/10 mil cel/mm3) na fase precoce do choque séptico. Relativamente à microbiologia dos isolados, a erradicação dos patógenos ocorreu para todos os pacientes após a infusão estendida contra Gram-negativos sensíveis (CIM: 2 mg/L), e de sensibilidade intermediária (CIM 4mg/L) como a K. pneumoniae e P. aeruginosa, enquanto a infusão intermitente garantiu erradicação de patógenos apenas até CIM 2 mg/L. Conclusão: Evidenciou-se a superioridade da infusão estendida frente à infusão intermitente na cobertura dos dois antimicrobianos, no alvo terapêutico considerado 100%fΔT>CIM. Registraram-se alterações na farmacocinética destes agentes nos pacientes frente aos dados reportados para voluntários sadios. Diferença significativa entre grupos (G1/G2) foi encontrada com relação meia vida biológica, e ao volume de distribuição tanto pata a piperacilina quanto para o meropenem

Background: Meropenem (MER) and Piperacillin/Tazobactam (PTZ), antimicrobial betalactam agents are widely prescribed to burn patients from the Intensive Care Unit (ICU) with nosocomial infections caused by Gram-negative strains. Change in the pharmacokinetics of critically ill patient occurs during the systemic inflammatory response syndrome (SIRS) at the course of septic shock. Then, the recommended dose administered by intermittent infusion, 0.5 hr cannot reach the target against gram-negative strains MIC > 2 mg/L. Subject: To investigate drug effectiveness of the beta-lactams piperacilin and meropenem in extended infusion compared to the recommended intermittent infusion in critically ill septic burn patients using pharmacokinetic-pharmacodynamic (PK/PD) approach. Ethics, Casuistry and Methods: All authors declared there is no conflict of interests. Ethical approval CAAE, register 07525118.3.0000.0068. It was investigated in the study protocol 36 septic burn patients of both genders (12M / 24F), undergoing antimicrobial therapy with PTZ 4.5 g q6h or MER 1g q8h. Based on the chosen antimicrobial therapy and drug infusion prescribed by the physician, patients were stratified in groups with intermittent 0.5h infusion (G1) or with the extended 3h infusion (G2), both groups with 16 patients each. Two blood samples were collected at the steady state (1.5mL / each), at the 3rd and 5th hrs of starting the infusion. Serum levels were measured by liquid chromatography. Pharmacokinetics (PK) of MER or PTZ was compared to data reported in healthy volunteers for both groups of patients. PK/PD approach was applied to estimate the drug effectiveness index (fΔT> MIC) and to assess the probability of target attained (PTA) based on the recommended PK/PD target, 100% fΔT> MIC. Results and discussion: Characteristics of patients admission G1/G2 were: Clcr 115(90- 148)/127(90-170) ml/min; 30(24-31)/27(24-34) yrs, 70(61-75)/71(65-75) kg, 30(20- 42)/33.9(18-38.4)% total burn surface area, SAPS3 53(45-57)/48(37.8-59.5), medians (interquartile): thermal trauma occurred (17/16), electric trauma (1/2), inhalation injury (11/11), mechanical ventilation (9/16) and vasopressors required in 15/8 patients. It was demonstrated that different PK changes occurred for both beta-lactam agents after the extended or intermittent infusion by comparison with data reported in healthy volunteers. PK changes were related to the prolongation of biological half-life and increases on volume of distribution with impact on pharmacodynamics. On the other hand, meropenem total body clearance reduced by 50% at the earlier period of septic shock could be explained by the reduction of MER-transporters expression in the tubular renal secretion, once only patients with renal function preserved were included in the study protocol. Inflammatory biomarkers increased at the earlier period of septic shock: C-rp 232/183mg/L; leukocytes 11/14*103cel/mm3, neutrophils 9/10*103cel/mm3, medians, G1/G2. Clinical and microbiological cure was obtained for all patients of G1 against MIC < 2mg/L after intermittent 0.5 h infusion; while PK/PD target was attained for G2 patients undergoing antimicrobial therapy with MER or PTZ by extended infusion against gram negative strains K. pneumoniae, P. aeruginosa up to MIC 4mg L. Conclusion: Superiority of the extended infusion over intermitent infusion was obtained for the two antimicrobials was evidenced, in the therapeutic target considered 100%fΔT>CIM. Changes in the pharmacokinetics of these agents were recorded in patients compared to data reported for healthy volunteers. A significant difference between groups (G1/G2) was found in relation to biological half-life and volume of distribution for both piperacillin and meropenem

A comprehensive review of integrative pharmacology-based investigation: A paradigm shift in traditional Chinese medicine

Over the past decade, traditional Chinese medicine (TCM) has widely embraced systems biology and its various data integration approaches to promote its modernization. Thus, integrative pharmacology-based traditional Chinese medicine (TCMIP) was proposed as a paradigm shift in TCM. This review focuses on the presentation of this novel concept and the main research contents, methodologies and applications of TCMIP. First, TCMIP is an interdisciplinary science that can establish qualitative and quantitative pharmacokinetics-pharmacodynamics (PK-PD) correlations through the integration of knowledge from multiple disciplines and techniques and from different PK-PD processes

Progress in Application of Population Pharmacokinetic and Pharmacodynamic Models in Research on Traditional Chinese Medicine / 中国实验方剂学杂志

In recent years， the role of quantitative pharmacological models in applicable population of drugs and dose optimization has been widely recognized. In order to improve the efficiency of clinical development and optimize clinical rational drug use， quantitative pharmacological models are being gradually introduced into the research of traditional Chinese medicine （TCM）. There are various types of quantitative pharmacological models， among which the following three models are commonly used：①Population pharmacokinetic （PPK） model， which is mainly used to explore the pharmacokinetic characteristics in different populations.②Pharmacokinetic-pharmacodynamic （PK-PD） model， which is used to reveal the internal relationship among dose， time and efficacy. ③PPK-PD model， which integrates both the characteristics of PPK model and PK-PD model. The paper summarizes the application of the above three models in TCM， and extracts the main ideas and methods of TCM model research， in order to provide reference for clinical research and rational use of TCM.

Research progress and thinking on the metabolism of polysaccharide drugs in vivo and the key technology of PK/PD / 中国临床药理学与治疗学

Polysaccharide drugs are a type of safe and effective natural drug with a wide range of pharmacological activity such as anti-tumor, immunomodulation, and oxidation, and polysaccharide drugs are currently more concerned. However, since the molecular weight of the polysaccharide is quite large, most of which do not have ultraviolet absorption and fluorescent groups, which makes the qualitative and quantitative analysis of polysaccharides are relatively difficult. In addition, endogenous sugar substances may also cause certain interference to polysaccharide assay in biological samples, and therefore, in vivo metabolism and PK/PD key technologies in polysaccharide drugs have been research hotspots. This paper summarizes the relevant literature published in recent years, reviewing the biological activity and pharmacokinetics of polysaccharide drugs, proposing gut bacteria may be potential "organ" affecting metabolism and efficacy of polysaccharide drugs, and providing thoughts on gut bacteria mediating polysaccharide drugs in vivo and key technology research of PK/PD, in order to provide more scientific ideas for pharmacokinetics, pharmacological research and molecular mechanisms of polysaccharide drugs.

Abordagem Farmacocinética -Farmacodinâmica (PK/PD) Em Pacientes Sépticos Grandes Queimados: Avaliação do Meropenem Em Adultos Jovens Após 1g Q8h, Infusão Estendida / Pharmacokinetic -Pharmacodynamic Approach (PK/PD) In Septic Burn Young Adult Patients: Meropenem 1g q8h, extended infusion

Introdução: O Meropenem é um carbapenêmico de amplo espectro, prescrito na terapia do choque séptico nos pacientes graves adultos de UTI, com infecções graves causadas por patógenos Gram-negativos susceptíveis. Objetivo: Avaliar a efetividade do Meropenem em pacientes sépticos queimados, investigar a farmacocinética na fase precoce e na fase tardia durante o curso do choque séptico e o impacto no desfecho clínico. Ética, Casuística e Procedimentos: Aprovação ética, registro CAAE07525118.3.0000.0068; nenhum conflito de interesse declarado foi obtido dos autores. Após assinatura do TCLE pelo responsável legal, o paciente foi incluído no protocolo. Investigou-se a população de 15 pacientes sépticos grandes queimados, adultos de ambos os gêneros (10 M/ 5F) com função renal preservada (Clcr> 50 ml/min). As características demográficas da população de pacientes incluídos foram idade de 37(33 -41) anos, 71(59,5 - 80,0) kg e índice de massa corpórea de 24,3(20,6-24,7) kg/m2, medianas (interquartil). Registrou-se o escore SAPS*3 54(47-59) de admissão dos pacientes na UTI; a superfície corpórea total queimada foi de 33% (18,3-34,4), SCTQ medianas (interquartil). A lesão inalatória e o uso de vasopressores foram registrados em 12/15 pacientes após trauma térmico/ elétrico (10/5). Após intubação orotraqueal, a ventilação mecânica foi registrada em 13/15 pacientes. A terapia empírica do choque séptico com Meropenem no regime de 1g q8h, por infusão estendida de 3 horas, foi iniciada após a coleta das culturas. Realizou-se coleta seriada de amostras sanguíneas para dosagem sérica do antimicrobiano por cromatografia líquida. Aplicou-se o modelo aberto monocompartimental para estudo da farmacocinética e estimativa dos parâmetros, meia vida biológica, depuração total corporal e volume de distribuição. A abordagem farmacocinética-farmacodinâmica (PK-PD) foi baseada na dosagem sérica do Meropenem e na taxa de eliminação, para estimativa do índice de predição de efetividade (% ƒ Δ?T> CIM), considerando o novo alvo terapêutico de 100% ƒ Δ?T> CIM. Utilizou-se estatística não paramétrica pela aplicação do teste de Wilcoxon para dados pareados e testes de correlação linear. Resultados e Discussão: Registrou-se alteração dos parâmetros farmacocinéticos nos pacientes sépticos investigados frente aos dados reportados para voluntários sadios. Evidenciou-se redução na taxa de eliminação e da depuração total corporal; o prolongamento da meia vida biológica ocorreu pelo aumento do volume de distribuição. Estas alterações impactaram estendendo a cobertura do Meropenem, na fase precoce do choque séptico, contra os patógenos de susceptibilidade intermediária com CIM 4 mg/L. Conclusão: A cobertura do Meropenem foi garantida contra os patógenos isolados até CIM 2 mg/L para todos os pacientes. Adicionalmente, ocorreu a erradicação de patógenos de susceptibilidade intermediária CIM 4 mg/L, pela cobertura que foi atingida apenas na fase precoce do choque séptico. Então, a abordagem PK / PD contribui para a obtenção do resultado

Background: Meropenem is a carbapenêmic, agent largely prescribed to septic patients in the Intensive Care Units with severe infections caused by Gram-negative susceptible strains. Objective: To evaluate Meropenem effectiveness in ICU septic burn patients and to investigate pharmacokinetic changes that could impact the desired outcome by eradication of Gram-negative strains of intermediate susceptibility. Ethics, Casuistry and Methods: Ethical approval register CAEE 07525118.3.0000.0068was obtained; no conflicts of interest to declare were obtained from all authors. Fifteen burn adult patients of both genders (10 M/ 5F) with preserved renal function (Clcr> 50 ml/min) were investigated after TCLE signed. Demographic characteristics of patients included were: 37(33 -41) years, 71(59.5- 80.0) kg, 24.3 (20.6-24.7) kg/m2 body mass index, medians (quartiles). ICU patients admission was based on SAPS*3 score of 54(47-59), 33% (18.3-34.4) TBSA medians (quartiles). Inhalation injury and vasopressors requirements were in 12/15 patients after fire/electricity (10/5, proportion). Mechanical ventilation was necessary in 13/15 patients. Antimicrobial therapy of septic shock with meropenem 1g q8h 3 hours infusion started, after cultures collection. A serial of blood samples was collected from the central catheter after a minimum of 48 hours of Meropenem therapy for drug serum measurements by liquid chromatography. One compartment open model was applied to estimate PK data related to the elimination rate constant, biological half-life, total body clearance and volume of distribution PK/PD approach was based on serum trough levels and elimination rate constant to estimate the predictive index of drug effectiveness (% fΔT>CIM), based on the new PK/PD target 100% fΔT>CIM. Non parametric statistics was applied, Wilcoxon test for paired data and linear correlations. Results: Pharmacokinetic changes occurred in septic burn patients investigated by comparison with results reported in healthy volunteers as follows by the reduction on elimination rate constant and also on total body clearance, in spite of preserved renal function for all patients included. In addition, a prolongation of biological half-life occurred as a consequence of increases on volume of distribution. Pharmacodynamics was impacted by PK changes only at the earlier period of septic shock, once pathogens isolated of intermediate susceptibility up to MIC 4 mg/L were eradicated. Conclusion: Meropenem effectiveness was guaranteed against Gram-negative up to MIC 2 mg/L strains isolated for all patients. In addition, eradication of pathogens of intermediate susceptibility MIC 4 mg/L strains occurred only at the earlier period of septic shock. Then, PK/PD approach contributes to desired outcome achievement

Applications of model-informed drug development (MIDD) on new drug research and development / 中国临床药理学与治疗学

Model-informed drug development (MIDD) refers to the application of various mathematical models in drug development, in order to facilitate the decision-making process. There have been common and mature applications of MIDD to address drug development and regulatory questions in interactional industries and advanced regulatory agencies, especially the US FDA. However, its application in innovative drug development is relatively rare in China. Representative case studies, clinical pharmacology review ex-periences, and relevant guidelines are reviewed in this article to present a preliminary discussion on the main applications of MIDD. Additionally, several suggestions for the application of MIDD in new drug development as well as general considerations for new drug registration are proposed in this paper, for the discussion or reference of industries and researchers.

Antipyretic effect of active components of Mahuang Decoction and its correlation with pharmacokinetics in febrile rats / 中国中药杂志

To investigate the antipyretic effect of active components of Mahuang Decoction in febrile rats, and explore its correlation with pharmacokinetics at different time points. The feverished rat models were induced by dry yeast, and intragastrically administered with the effective components of Mahuang Decoction with different orthogonal compatibility ratios. At different time points after administration, body temperature was measured; blood was taken from orbital vena plexus, and the contents of interleukin-6(IL-6), interleukin-1β(IL-1β), and tumor necrosis factor-α(TNF-α) in rat serum were determined with the kits. Combined with the pharmacokinetic data of the seven effective components in Mahuang Decoction, PK-PD(pharmacokinetics-pharmacodynamics) data fitting was conducted by using the analysis method of non-atrioventricular model, and then the pharmacodynamic parameters were calculated to determine the optimal binding model. The results showed that the effective components of Mahuang Decoction inhibited the release of heat-causing factors IL-6, IL-1β and TNF-α, and reduced the increase of body temperature. There was a significant lag between drug effect and blood drug concentration, which was consistent with Sigmoid-E_(max) model. The model fitting value showed a good correlation with mea-sured data, which could be used to evaluate and predict the correlation between PK and PD in Mahuang Decoction, and further applied to the multiple-indicator and multiple-effect study of PK-PD in other compound traditional Chinese medicines.

Orthogonal compatibility study on main effective parts of Yangyin Tongnao Granules based on pharmacokinetics and pharmacodynamics / 中草药

Objective: To investigate the pharmacokinetic and pharmacodynamic changes of Yangyin Tongnao Granules (YTG) in cerebral ischemia reperfusion rats after the compatibility of main effective parts (total alkaloids, total flavonoids, total saponins and total phenolic acids). Methods: By using the orthogonal design to research the main effective parts of YTG, nine different dosage ratios combinations were formed, which were used for oral administration in cerebral ischemia reperfusion rats. High performance liquid chromatography-diode array detector (HPLC-DAD) was used to determine the concentration of puerarin, ferulic acid, and ligustrazine in rat plasma at different time points. The non-compartmental model was used to fit the pharmacokinetic parameters by Drug and Statistics (DAS) 3.2.6 software. The total quantum statistical moment analysis method and comprehensive evaluation method were used to evaluate the total pharmacokinetic characteristics. Meanwhile, the content of superoxide dismutase (SOD) and catalase (CAT) were determined by enzyme-linked immunosorbent assay (ELISA) kits. Finally, the PK-PD model and the quantitative equations between drug concentration and efficacy were obtained. Results: The pharmacokinetic characteristics of puerarin, ferulic acid and ligustrazine in cerebral ischemia-reperfusion rats were different. Total statistical moment and comprehensive score study showed that different combinations had different effects on ACUT, mean retention time (MRT), and comprehensive evaluation. The effective parts inhibited the reduction of oxidation indexes such as SOD and CAT. Sigmoid-Emax models were adopted in all PK-PD models, and the fitting results had a good correlation with the measured data. The R values were more than 0.85. Conclusion: Compatibility of YTG activity parts had a certain effect on their pharmacokinetic behaviors and antioxidation in model rats. The total quantum statistical moment analysis and comprehensive evaluation method can be used to study the pharmacokinetics of multi-component traditional Chinese medicine prescriptions. PK-PD model could be used to predict and evaluate the correlation between pharmacokinetics and pharmacodynamics of traditional Chinese medicine prescriptions.

Pharmacokinetic-pharmacodynamic link model of Periploca forrestii based on rheumatiod arthritis rat model / 中草药

Objective: To establish a pharmacokinetic (PK)-pharmacodynamic (PD) model of Periploca forrestii. Methods: The right hindfoot footpad of rats were 0.1 mL complete Freund's Adjuvant (CFA) to establish adjuvant arthritis (AA) rat model. Rats were ig P. forrestii extract (87 g/kg, twice a day for 14 d) and blood were collected via tail vein at 5, 15, 30, 45 min, 1, 1.5, 2, 3, 4, 6, 8, 12, 24 h after the last administration. The concentrations of 3-O-caffeoylquinic acid, 4-O-caffeoylquinic acid, 5-O-caffeoylquinic acid in plasma samples were detected by HPLC-mass spectrometry (HPLC-MS/MS) to obtain the drug concentration-time curve. The level of interleukin-1β (IL-1β), rheumatoid factor (RF), tumor necrosis factor-α (TNF-α) in plasma samples were determined by kit to obtain the time-effect curve. WinNonLin software was used to fit the PK parameters of P. forrestii, and the time-effect relationship was fitted to obtain the PD parameters. According to the PD parameters, the PK-PD model of P. forrestii was established. Results: The PK-PD model of P. forrestii according to the WinNonLin software was fitted in accordance with the Inhibitory Effect Sigmoid E0 model, in which the blood concentrations of 3-O-caffeoylquinic acid, 4-O-caffeoylquinic acid, 5-O-caffeoylquinic acid could be calculated based on the potency values, and the potency values could be calculated based on the blood concentrations. Conclusion: There was a correlation between the concentrations of IL-1β, RF, TNF-α and 3-O-caffeoylquinic acid, 4-O-caffeoylquinic acid and 5-O-caffeoylquinic acid. These three components in P. forrestii extract could inhibit the secretion of IL-1β, RF and TNF-α to treat rheumatiod arthritis.

Pharmacokinetic/pharmacodynamic models of anti-tumor agents in xenograft mice: historical review, recent advances, and application in drug development / 药学学报

Xenograft mice are preclinical animal models of tumors and are widely utilized in anti-tumor research. PK/PD modeling of anti-tumor agents is an approach that can capture the time profile of the "dose-plasma concentration-biomarker level-tumor volume" process based on experimental data from xenograft mice using a non-linear mixed-effect model. PK/PD modeling can help optimize the dosing regimen for anti-tumor therapy, evaluate any synergistic effect and help identify an optimal schedule for combination therapy, as well as providing a preliminary estimate of a drug's efficacy and anti-tumor potency in the human body. PK/PD modeling can also help by quantitatively explaining the mechanism of the tumor-inhibitory effect as indicated by changes in biomarker levels after a drug acts on its target. This article provides a systematic summary of the background, application range, and limitations of the mainstream anti-tumor agent PK/PD models. Recent advances in model structure development are reviewed in detail. Finally, we discuss promising applications of PK/PD models in anti-tumor medicine development from the perspective of a drug's mechanism of action, optimization of combination therapy schedules, and their clinical translation.

Pharmacokinetics/Pharmacodynamics models of veterinary antimicrobial agents

Misuse and abuse of veterinary antimicrobial agents have led to an alarming increase in bacterial resistance, clinical treatment failure, and drug residues. To address these problems, consistent and appropriate dosage regimens for veterinary antimicrobial agents are needed. Pharmacokinetics/Pharmacodynamics (PK/PD) models have been widely used to establish rational dosage regimens for veterinary antimicrobial agents that can achieve effective prevention and treatment of bacterial diseases and avoid the development of bacterial resistance. This review introduces building methods for PK/PD models and describes current PK/PD research progress toward rational dosage regimens for veterinary antimicrobial agents. Finally, the challenges and prospects of PK/PD models in the design of dosage regimens for veterinary antimicrobial agents are reviewed. This review will help to increase awareness of PK/PD modeling among veterinarians and hopefully promote its development and future use.

Advances of the mode of clinical pharmacy care in the era of precision medicine / 医学研究生学报

Precision medicine has become a new mode of modern medicine, and personalized medication is the important embodiment of clinical application of precision medicine. The advances of life science technologies greatly facilitated precision medicine, and also promoted the shift of the mode of clinical pharmacy care from rational drug use and individualized medication to precision medication. To achieve"one person, one mode" clinical dosage regimens,it is necessary to rely on the supports of advanced life science technologies and precisely analyzing and accurately characterizing the biomarker clusters related to individual differences among patients, pathological differences of disease, and disease progression. This article illustrated the recent advances in the application of pharmacokinetics/pharmacodynamics, omics technology and liquid biopsy to the design of dosage regimen, prediction of therapeutic effect and adverse drug reactions, etc. in the era of precision medicine. Furthermore, the development direction of the new model of clinical pharmaceutical care faced on the precision medicine is prospected.

Study on pharmacodynamic material basis of Naomaitong to protect neuronal cells based on PK-PD model / 中国中药杂志

The PK-PD correlation models by using pharmacodynamics and pharmacokinetics were applied to study the material basis of Naomaitong,a clinical empirical prescription for the treatment of cerebral apoplexy,in inhibiting the death of PC12 nerve cells induced by Na_2S_2O_4 and Glu. In this experiment,PC12 cell death models induced by Na_2S_2O_4 and Glu were established respectively.With LDH lateral leakage and NO content as pharmacodynamic indexes,PK-PD model was established by SVM algorithm to evaluate the effective components of Naomaitong in inhibiting neural cell death. The results showed that the positive correlation of emodin methyl ether-8-O-β-D-glucopyranoside,aloe emodin,chrysophanol,rhein,emodin,ginsenoside Rg1,ginsenoside Rc,3'-methoxypuerarin and ligustilide was significant,obviously improving the LDH release and NO content. The results indicated that the contribution of Radix Puerariae Lobatae Radix and Rhei Radix et Rhizoma in Naomaitong could protect the nerve cell death induced by Na_2S_2O_4 and Glu respectively. PK-PD model was used to screen the neuroprotective components in Naomaitong,revealing the possible pharmacodynamic material basis of Naomaitong in the treatment of cerebral ischemia injury.