Good clinical research practice (GCRP) in pharmacodynamic studies of neuromuscular blocking agents III: The 2023 Geneva revision

The set of guidelines for good clinical research practice in pharmacodynamic studies of neuromuscular blocking agents was developed following an international consensus conference in Copenhagen in 1996 (Viby-Mogensen et al., Acta Anaesthesiol Scand 1996, 40 , 59–74); the guidelines were later revised and updated following the second consensus conference in Stockholm in 2005 (Fuchs-Buder et al., Acta Anaesthesiol Scand 2007, 51 , 789–808). In view of new devices and further development of monitoring technologies that emerged since then, (e.g., electromyography, three-dimensional acceleromyography, kinemyography) as well as novel compounds (e.g., sugammadex) a review and update of these recommendations became necessary. The intent of these revised guidelines is to continue to help clinical researchers to conduct high-quality work and advance the field by enhancing the standards, consistency, and comparability of clinical studies. There is growing awareness of the importance of consensus-based reporting standards in clinical trials and observational studies. Such global initiatives are necessary in order to minimize heterogeneous and inadequate data reporting and to improve clarity and comparability between different studies and study cohorts. Variations in definitions of endpoints or outcome variables can introduce confusion and difficulties in interpretation of data, but more importantly, it may preclude building of an adequate body of evidence to achieve reliable conclusions and recommendations. Clinical research in neuromuscular pharmacology and physiology is no exception.     

基于药动学与药效学相关联的养阴通脑颗粒主要有效部位正交配伍研究

目的探讨养阴通脑颗粒主要有效部位(总生物碱、总黄酮、总皂苷、总酚酸)配伍后在脑缺血再灌注模型大鼠体内药物浓度及其药动学与药效学变化。方法采用正交试验法组成上述主要有效部位用量配比不同的9个组方,供脑缺血再灌注模型大鼠ig给药,高效液相色谱-二极管阵列检测器(HPLC-DAD)测定不同时间点血浆中的葛根素、阿魏酸和川芎嗪血浆药物浓度。DAS 3.2.6软件以非房室模型拟合药动学参数,并运用总量统计矩法和综合评分法对整体药动学特征进行评价。同时采用酶联免疫吸附测定(ELISA)法测定大鼠血浆中超氧化物歧化酶(SOD)和过氧化氢酶(CAT)的含量。最后进行药动学-药效学(PK-PD)模型研究,获得各药物浓度与药效之间的定量方程。结果葛根素、阿魏酸和川芎嗪在模型大鼠体内的药动学特征有所差异。总量统计矩和综合评分研究表明不同配伍对总量零阶矩、总量平均滞留时间、综合评分等参数影响不一。主要有效部位正交配伍给药后,一定程度上会抑制脑缺血再灌注大鼠血浆中SOD和CAT的降低。各PK-PD模型均采用Sigmoid-Emax模型,拟合结果与实测数据之间相关性良好,R值均大于0.85。结论养阴通脑颗粒主要有效部位配伍对模型大鼠体内的药动学行为和抗氧化指标具有一定影响;中药复方多成分药物代谢动力学可采用总量统计矩和综合评分法进行研究;PK-PD结合模型可用于中药复方多成分药动学与药效学之间相关性的评价与预测。     

Understanding the Influence of Nanocarrier-Mediated Brain Delivery on Therapeutic Performance Through Pharmacokinetic-Pharmacodynamic Modeling

This study aimed at evaluating how encapsulation in a regular nanocarrier (NC) (providing extended circulation time) or in a brain-targeting NC (providing prolonged circulation time and increased brain uptake) may influence the therapeutic index compared with the unformulated drug and to explore the key parameters affecting therapeutic performance using a model-based approach. Pharmacokinetic (PK) models were built with chosen PK parameters. For a scenario where central effect depends on area under the unbound brain concentration curve and peripheral toxicity relates to peak unbound plasma concentration, dose-effect and drug-side effect curves were constructed, and the therapeutic index was evaluated. Regular NC improved the therapeutic index compared with the unformulated drug due to reduced peripheral toxicity, while brain-targeting NC enhanced the therapeutic index by lowering peripheral toxicity and increasing central effect. Decreasing drug release rate or systemic clearance of NC with drug still encapsulated could increase the therapeutic index. Also, a drug with shorter half-life would therapeutically benefit more from a NC encapsulation. This work provides insights into how a NC for brain delivery should be optimized to maximize the therapeutic performance and is helpful to predict if and to what extent a drug with certain PK properties would obtain therapeutic benefit from nanoencapsulation.     

Antimicrobial dosing in critically ill patients with sepsis-induced acute kidney injury

Severe sepsis often leads to multiple organ dysfunction syndromes (MODS) with acute kidney injury (AKI). AKI affects approximately, 35% of Intensive Care Unit patients, and most of these are due to sepsis. Mortality rate of sepsis-induced AKI is high. Inappropriate use of antimicrobials may be responsible for higher therapeutic failure, mortality rates, costs and toxicity as well as the emergence of resistance. Antimicrobial treatment is particularly difficult due to altered pharmacokinetic profile, dynamic changes in patient''s clinical status and, in many cases, need for renal replacement therapy. This article aims to describe the appropriate antimicrobial dosing and reviews the factors contributing to the difficulties in establishing precise guidelines for antimicrobial dosing in sepsis-induced AKI patients. Search strategy: Text material was collected by systematic search in PubMed, Google (1978–2013) for original articles.     

Pharmacokinetic/pharmacodynamic profiling of imipenem in patients admitted to an intensive care unit in India: A nonrandomized,cross-sectional,analytical, open-labeled study

Results:The difference in the plasma imipenem concentration between the gastrointestinal and the nongastrointestinal groups was significant at 2 h (P = 0.015) following drug dosing; while the difference was significant between the skin/cellulitis and nonskin/cellulitus groups at 2 h (P = 0.008), after drug dosing. The imipenem levels were above the MIC and 5 times the MIC for the isolated organism in 96.67% and 50% of the patients, respectively.Conclusions:The pharmacokinetic profile of imipenem does not vary according to the locus of an infection in critically ill patients. Imipenem, 3 g/day intermittent dosing, maintains a plasma concentration which is adequate to treat most infections encountered in patients admitted to an ICU. However, a change in the dosing regimen is suggested for patients infected with organisms having MIC values above 4 mg/L.     

Pharmacodynamic analysis of apremilast in Japanese patients with moderate to severe psoriasis: Results from a phase 2b randomized trial

We evaluated the pharmacodynamic effects of apremilast in 69 patients who were included in biomarker subanalyses of a phase 2b study that demonstrated the long‐term safety and efficacy of apremilast in Japanese adults with moderate to severe psoriasis. The association between cytokine levels and Psoriasis Area and Severity Index (PASI) improvement was evaluated using linear regression and Spearman’s rank correlation coefficient analysis. At baseline, median plasma levels of interleukin (IL)‐17A, IL‐17F and IL‐22 were elevated versus reference values for healthy individuals, whereas tumor necrosis factor‐α levels were close to normal. With apremilast 30 mg b.i.d., there were significant associations between percentage change in PASI score and percentage change in IL‐17A, IL‐17F and IL‐22 levels at week 16. Findings demonstrate that the efficacy of apremilast in psoriasis is associated with inhibition of key cytokines involved in the pathology of psoriasis.     

Effect of Food on the Pharmacokinetic and Pharmacodynamic Profiles of Hetrombopag in Healthy Volunteers

PurposeHetrombopag, a novel, oral small molecule thrombopoietin receptor agonist, exhibits an obvious thrombocytopoietic effect with good safety. Hetrombopag is currently under clinical development for the treatment of chronic idiopathic thrombocytopenic purpura (ITP). The objectives of this study were to assess the effect of high-fat and high-calorie food on the pharmacokinetic and pharmacodynamic (PK/PD) profiles of hetrombopag in healthy volunteers.MethodsAn independent, single-dose, open-label, randomized-sequence, crossover trial was conducted. Healthy volunteers received hetrombopag 7.5-mg tablets in the fasted state or with a high-fat, high-calorie breakfast. The effects of the high-fat and high-calorie food on the PK/PD profiles of hetrombopag were evaluated by using a noncompartmental analysis and a semi-physiological model.FindingsTwelve Chinese healthy volunteers were enrolled. Mean plasma AUC_0–t and C_max decreased by 98.7% and 95.0%, respectively, when hetrombopag was administered with high-fat and high-calorie food. The semi-physiological PK/PD model analysis showed that the absorption rate constant at the first absorption site was almost halved at the fed condition. The change in platelet counts in the fed condition was not sufficiently as sensitive as that in the fasted condition.ImplicationsHigh-fat and high-calorie food were associated with significantly reduced systemic exposure and platelet count sensitivity. Thus, hetrombopag should be taken in a fasted state to avoid the impact of food on bioavailability and platelet counts. ClinicalTrials.gov identifier: NCT02409394.