靶点介导的药物处置模型在单克隆抗体药物研发中应用的探讨

近年来,国内外诸多企业正在积极地进行单克隆抗体药物的研发和申报。作为一种大分子蛋白药物,单克隆抗体因其特殊的结构和生理性质,在体内的吸收、分布、代谢及排泄与小分子药物相比均存在较大差异。单抗具有的靶点介导的药物处置、非线性药动-代谢、时间依赖性、较长的半衰期等独特的药代动力学特征,使得其在药物研发过程中存在了一系列的挑战。合理的应用模型和仿真技术可帮助研究者充分发掘数据信息、预测临床试验结果、指导临床试验设计以及优化给药方案等,其中靶点介导的药物处置模型在单抗药物研发中的应用目前已有一些探索。本文将通过对单抗药物药动学特征的介绍,探讨靶点介导的药物处置模型在单抗药物研发中应用的可行性和必要性,以期帮助研究者科学、高效地进行单抗类药物的研发。     

人体中伊曲康唑及其活性代谢产物羟基伊曲康唑的整合药代动力学研究

目的: 羟基伊曲康唑(OH-ITZ)为目前临床一线抗真菌药伊曲康唑(ITZ)的主要活性代谢产物,其与ITZ有着相似的抗菌活性,且血药浓度较母体药物高,因此OH-ITZ的体内过程对临床疗效的影响研究不容忽视。本文旨在建立灵敏、快速的液相色谱-串联质谱法同时测定人血浆中ITZ及OH-ITZ,并应用整合药代动力学模型进行整体评价。方法: 血浆样品经沉淀蛋白后,以乙腈(甲酸 0.1%)-水(甲酸 0.1%)为流动相梯度洗脱,Zorbax XDB C₁₈柱分离,采用电喷雾电离源,以多反应监测(MRM)方式进行正离子检测。定量分析所用的离子反应分别为m/z 705 →m/z 392(ITZ),m/z 721→m/z 408(OH-ITZ)和m/z 386→m/z 122(内标,丁螺环酮)。结果: 测定血浆中ITZ及OH-ITZ的线性范围均为 0.50~500 ng/mL,日内、日间精密度(RSD)均小于 12.4%,准确度(RE)均在±7.5%以内;整合药动学研究结果显示综合浓度药-时曲线符合口服给药药物消除规律,整合后主要药动学参数t_1/2和AUC_0-∞分别为 19.5 h,5754 ng·h·mL^-1。结论: 本方法运行时间短、选择性强、灵敏度高、操作简便、血浆用量少,适用于ITZ及OH-ITZ的临床药代动力学研究;其整合药动学模型研究所获参数能够表征ITZ和OH-ITZ的整体处置规律,符合经典药代动力学模型特征。     

Synthesis and Biological Characterization of Amidopropenyl Hydroxamates as HDAC Inhibitors

A series of amidopropenyl hydroxamic acid derivatives were prepared as novel inhibitors of human histone deacetylases (HDACs). Several compounds showed potency at <100 nM in the HDAC inhibition assays, sub‐micromolar IC₅₀ values in tests against three tumor cell lines, and remarkable stability in human and mouse microsomes was observed. Three representative compounds were selected for further characterization and submitted to a selectivity profile against a series of class I and class II HDACs as well as to preliminary in vivo pharmacokinetic (PK) experiments. Despite their high microsomal stability, the compounds showed medium‐to‐high clearance rates in in vivo PK studies as well as in rat and human hepatocytes, indicating that a major metabolic pathway is catalyzed by non‐microsomal enzymes.     

CYP2A6*4基因多态性对右美托咪定药动学的影响

目的: 在CYP2A6*4突变频率高的中国人中测定CYP2A6*4等位基因对右美托咪定药代动力学的影响,为临床提供参考。方法: 31名手术患者通过静脉泵接受0.5 μg/kg右美托咪定后,抽取多个时间点的血样,测定血药浓度以及CYP2A6*4的多态性,并进行统计分析。结果: 9名患者为*1/*4或*4/*4,22名患者为*1/*1。主要药代动力学参数如下,曲线下面积（AUC）为（1 396.19±332.47）h·ng·L^-1,峰值血药浓度（C _max）为（495.50±104.90）ng/L,分布容积（V）为（0.68±0.20）L/kg,清除率（CL）为（0.38±0.11）L·h ^-1·kg^-1,分布半衰期（t _1/2α）为（0.05±0.01）h,消除半衰期（t _1/2β）为（2.53±0.04）h。在CYP2A6*1/*1,*1/*4和*4/*4患者中未发现显著的药代动力学差异。结论: 中国患者使用右美托咪定后,t _1/2β与公布的一致,但t _1/2α,V和CL较低。在制定右美托咪定的精准治疗方案时,可不予考虑CYP2A6*4突变。     

Brain Disposition of Antibody-Based Therapeutics: Dogma,Approaches and Perspectives

Due to their high specificity, monoclonal antibodies have been widely investigated for their application in drug delivery to the central nervous system (CNS) for the treatment of neurological diseases such as stroke, Alzheimer’s, and Parkinson’s disease. Research in the past few decades has revealed that one of the biggest challenges in the development of antibodies for drug delivery to the CNS is the presence of blood–brain barrier (BBB), which acts to restrict drug delivery and contributes to the limited uptake (0.1–0.2% of injected dose) of circulating antibodies into the brain. This article reviews the various methods currently used for antibody delivery to the CNS at the preclinical stage of development and the underlying mechanisms of BBB penetration. It also describes efforts to improve or modulate the physicochemical and biochemical properties of antibodies (e.g., charge, Fc receptor binding affinity, and target affinity), to adapt their pharmacokinetics (PK), and to influence their distribution and disposition into the brain. Finally, a distinction is made between approaches that seek to modify BBB permeability and those that use a physiological approach or antibody engineering to increase uptake in the CNS. Although there are currently inherent difficulties in developing safe and efficacious antibodies that will cross the BBB, the future prospects of brain-targeted delivery of antibody-based agents are believed to be excellent.     

盐酸普拉克索片在中国健康受试者的生物等效性试验

目的：研究盐酸普拉克索片与原研制剂森福罗的人体生物等效性。方法：24例健康受试者参加空腹试验,24例健康受试者参加餐后试验,均采用随机开放两周期交叉试验设计,分别于每周期单剂量口服0.25 mg盐酸普拉克索片受试制剂（T）或参比制剂（R）。采用液相色谱-串联质谱分析方法（LC-MS/MS）测定血浆中普拉克索浓度。用Phoenix WinNonlin 6.4计算药代动力学参数,其他统计分析工作使用SAS 9.3软件分析。结果：空腹组健康受试者口服受试制剂和参比制剂后的主要药代动力学参数（n=20）：Cmax分别为（481.15±102.21）、（497.25±133.31） pg/mL,Tmax分别为1.77（0.5,5）、1.50（0.5,5） h,AUC0-t分别为（6.18±1.49）、（6.20±1.28） pg·mL-1·h,AUC0-∞分别为（6.41±1.55）、（6.42±1.31） pg·mL-1·h,T1/2分别为（9.18±1.29）、（9.02±1.14） h。受试制剂Cmax、AUC0-t、AUC0-∞几何均数的90%置信区间分别落在参比制剂相应参数的92.20%～103.10%、94.06%～104.35%、94.17%～104.07%,均在80.00%～125.00%范围之间,符合生物等效性规定要求。高脂餐组健康受试者口服受试制剂和参比制剂后的主要药代动力学参数（n=22）：Cmax分别为（515.36±83.28）、（500.05±64.12）pg/mL,Tmax分别为2.00（1,4）、1.75（1,4）h,AUC0-t分别为（5.94±1.36）、（5.67±1.05）pg·mL-1·h,AUC0-∞分别为（6.16±1.43）、（5.88±1.11） pg·mL-1·h,T1/2分别为（8.92±2.00）、（8.85±1.98）h。受试制剂Cmax、AUC0-t、AUC0-∞几何均数的90%置信区间分别落在参比制剂相应参数的97.84%～107.41%、99.03%～108.79%、99.12%～108.68%,均在80.00%～125.00%范围内,符合生物等效性规定要求。结论：盐酸普拉克索片受试制剂和参比制剂在健康受试者体内具有生物等效性。     

肠道菌群对药物代谢动力学的影响及其在仿制药质量与疗效一致性评价中的思考

仿制药占我国化药市场的95%以上,其质量直接关系到国民用药的疗效和安全。以药代动力学参数为终点的生物等效性评价是仿制药质量和疗效一致性评价的重要内容。肠道菌群被认为对药物的药代动力学具有重要影响。本文综述了肠道菌群对药代动力学影响并分析其在仿制药质量与疗效一致性评价中的潜在意义。     

药物代谢创新模型：基因编辑大鼠和小肠3D类器官

药物代谢与药代动力学（drug metabolism and pharmacokinetics, DMPK）是研究药物的吸收（absorption）、分布（distribution）、代谢（metabolism）和排泄（excretion）过程的科学,评估药物的DMPK特征对药物的前期开发和后期临床精准用药至关重要。药物代谢模型的创新构建促进了药物DMPK评估体系的发展和完善。本文基于我们的研究成果,总结了药物代谢创新模型的最新进展与应用,主要关注以下两个方面：（1）CRISPR/Cas9（clustered regularly interspaced short palindromic repeats-CRISPR-associated）技术创新构建药物代谢酶（包括CYP2E1,CYP3A1/2,CYP2J3/10,CYP1A2）和药物转运体（包括P-gp,OATP1B2）基因敲除（knockout, KO）大鼠模型,并应用于DMPK及其生理功能相关研究;（2）创新性将小鼠和人小肠3D类器官（organoids）应用到ABC（P-gp, BCRP, MRP2）转运蛋白的功能研究。上述药物代谢创新动物模型和类器官模型,不仅有利于评价药物代谢酶和转运体在DMPK中的作用,还有助于深入认识其在机体正常生理活动中的作用功能。     

Evaluation of the Physicochemical Properties,Pharmacokinetics, and In Vitro Anticancer Effects of Docetaxel and Osthol Encapsulated in Methoxy Poly(ethylene glycol)-b-Poly(caprolactone) Polymeric Micelles

Docetaxel (DTX), a taxane-based anticancer drug, and osthol (OTH), a coumarin-derivative compound, have shown anticancer effects against different types of cancers through various mechanisms. However, these drugs have low solubility in water and low oral bioavailability, and thus their clinical application is difficult. To overcome these problems, we encapsulated DTX and OTH in methoxy poly(ethylene glycol)-b-poly(caprolactone) (mPEG-b-PCL) and conducted studies in vitro and in vivo. We selected a 1:4 ratio as the optimal ratio of DTX and OTH, through combination index analysis in A549 cancer cells, and prepared micelles to evaluate the encapsulation efficiency, drug loading, particle size, and zeta potential. The in vitro drug-release profile showed that DTX/OTH-loaded mPEG-b-PCL micelles could slowly release DTX and OTH. In the clonogenic assay, DTX/OTH-loaded mPEG-b-PCL micelles showed 3.7 times higher inhibitory effect than the DTX/OTH solution. Pharmacokinetic studies demonstrated that micelles in combination with DTX and OTH exhibited increased area under curve and decreased clearance values, as compared with single micelles.     

反相高效液相色谱法测定人血浆中氮烯菲林及其代谢产物

目的: 建立同时测定人血浆中氮烯菲林及其代谢产物的反相高效液相色谱法。 方法: 血样在加入内标后用乙酸乙酯进行两次萃取, 然后以反相柱分离, 在 345 nm 处以紫外检测器进行检测。 结果: 血样中没有明显的干扰峰出现, 氮烯菲林及其代谢产物洗脱快, 分离好, 线性范围分别为 0.05 ～40 mg·L^-1, 0.1 ～ 20 mg·L^-1 , 最 低 检 测 限 为0.05 mg·L^-1 , 相对回收率为 81.42%～ 104.67%, 变异系数小于 9.95 %。结论:: 本法快速、 灵敏、回收率高, 且萃取过程简单, 可用于氮烯菲林的药代动力学研究。