抗体偶联药物的分子特点及其药代动力学研究考虑

随着我国药物研发和临床试验水平的不断提高,近年来抗体偶联药物(Antibody-Drug Conjugate, ADC)的相关研究和注册申报也正在增多。ADC类药物由抗体、连接子和小分子毒素组成,在兼具高度靶向性和高细胞毒性优势的同时,由于其结构的多样性和复杂性,以及循环系统中释放的小分子毒素含量较低等特殊性,给其药代动力学研究带来了诸多挑战。本文将从ADC药物的分子设计、药代动力学特征和目标分析物等方面讨论,以期帮助读者更好的理解ADC药物的药代动力学研究。     

抗体偶联药物的临床应用及其耐药性优化对策的研究进展

抗体–药物偶联(ADC)是现代“精准医疗”需求下药学发展的必然趋势。从2000年第一款ADC药物的上市成功到2020年ADC药物的研发层出不穷。肿瘤靶向治疗的发展带动了ADC药物研发领域的快速兴起。ADC药物是使用具有特异性的单克隆抗体与具有生物活性的细胞毒素结合,将药物特异性递送至肿瘤表面位点,避免对正常细胞的杀伤,减少毒副作用。ADC为细胞毒性有效载荷提供了一种较为理想的递送方法。但是也必须清楚的认识到,由于肿瘤异质性、肿瘤代谢、肿瘤血供等多种因素导致的肿瘤耐药是ADC药物发展中所面临的一大挑战。从ADC药物的发展进程、临床应用及其所面临的耐药问题进行综述,探讨抗体偶联药物的临床应用及其所面临的挑战和策略。     

抗体偶联药物的研发进展和挑战

抗体偶联药物（ADC）由单克隆抗体与不同数目的小分子毒素通过连接子偶联组成,是近年来肿瘤学发展较快的药物类别之一。由于兼具单抗药物的高靶向性以及细胞毒素在肿瘤组织中高活性的双重优点,ADC药物可高效杀伤肿瘤细胞,较化疗药物不良反应更低,较传统抗体类肿瘤药物具有更好的疗效,是近年来肿瘤创新药研发的热点。随着新一代工程抗体展现出良好的治疗前景以及新药研发技术的不断突破,抗体偶联药物经历了三个发展阶段,技术日臻成熟,但ADC药物还存在诸多问题和挑战。本文主要从抗体偶联药物的研发历程、抗体、连接子、偶联技术及细胞毒素的类型等方面进行综述,为ADC创新药物研发提供参考。     

抗体偶联药物分析方法的概述及进展北大核心CSCD

单克隆抗体药物的靶点选择性非常高,但其药理活性普遍比较低。近年来抗体偶联药物(antibody-drug conjugate,ADC)的出现,正好弥补了单克隆抗体药物的缺点。ADC是一类通过化学偶联子将单克隆抗体和不同数目的小分子细胞毒素(效应分子)偶联起来的药物。这种新型的药物结合了单克隆抗体的高特异性和小分子毒素的高活性。ADC药物的分析工作非常困难和费时,主要归因于分析物的多样性及分析方法的复杂性。本文将对目前在ADC药物研究的不同方面如理化性质表征、药代动力学和药效学研究、以及免疫原性评价等所用的分析方法做出归纳和阐述,并讨论这些方法所面临的困难和挑战。     

肿瘤靶向药物抗体-药物偶联物的研究进展

抗体-药物偶联物(Antibody-drug conjugates,ADC)具有单克隆抗体的靶向特异性和细胞毒素的抗肿瘤能力,其利用化学接头将细胞毒性药物与单克隆抗体偶联,与肿瘤部位的靶抗原结合后释放毒素.尽管概念简单,但是结构设计复杂、药物副作用明显和疗效欠佳等问题为其进一步研究应用带来了挑战.随着新技术的出现,AD...     

设计新一代抗体药物偶联物

化疗依然是包括手术、放疗、以及靶向疗法在内的最重要的抗癌手段之一。尽管高效细胞毒素很多,但癌细胞和健康细胞之间微小的差别限制了这些抗癌化合物因为毒副作用在临床上的广泛应用。鉴于抗肿瘤单克隆抗体对肿瘤细胞表面抗原的特异性,抗体药物已经成为肿瘤治疗的标准疗法,但单独使用时疗效经常不尽人意。抗体药物偶联物(antibody drug conjugate,ADC)把单克隆抗体和高效细胞毒素完美地结合到一起,充分利用了前者靶向、选择性强,后者活性高,同时又消除了前者疗效偏低和后者副作用偏大等缺陷。其中抗体是ADC的制导系统,能够靶向性地把效应分子输送到肿瘤细胞,有效地提高了抗体本身对癌细胞的杀伤力。ADC包括抗体、接头(linker)和细胞毒素(也经常称为效应分子)三个组成部分。通过靶向特定抗原,ADC有效地渗透到肿瘤组织,并被肿瘤细胞吞噬进入酶溶体,释放效应分子。尽管ADC新药的开发已经获得前所未有的成功,技术上仍然有待进一步优化,其中包括被肿瘤细胞吞噬的效率、细胞毒素的活性以及效应分子的释放等。本文简单介绍ADC领域的研究进展,并试图从抗体、接头和效应分子三个方面,讨论提高ADC分子在循环系统的稳定性等一系列优化ADC分子特征的策略。对当前ADC领域技术上存在的问题,以及中国公司进入这个领域要面临的挑战进行深度分析,并提出一些积极的应对方案。     

眼镜蛇毒细胞毒素类免疫毒素研究进展

眼镜蛇毒细胞毒素类免疫毒素是将从眼镜蛇毒中分离纯化的细胞毒素与抗体或细胞因子偶联而得到的一类新型导向药物，它以抗体或细胞因子特异识别并结合靶细胞，通过细胞毒素破坏细胞膜而引起细胞死亡。由于细胞毒素类免疫毒素能高效、特异地杀伤靶细胞，因此选择眼镜蛇毒细胞毒素用于肿瘤导向治疗将是一条很有希望的途径。     

抗体药物偶联物的研究进展

传统的癌症化疗常伴随着系统毒性,靶向治疗已成为当今肿瘤研究领域的热点。抗体-药物偶联物(antibody drug conjugates,ADCs)利用单克隆抗体(m ABs)对肿瘤细胞表面过表达抗原的特异性,将"弹头"药物(细胞毒药物)选择性地输送到肿瘤细胞中以改善药物治疗窗。ADCs由"弹头"药物、抗体和药物的偶联链三个部分组成,其兼具了抗体的高特异性和细胞毒素的高活性。而随着抗体药物偶联物brentuximab vedotin(SGN-35,Adcetris)和trastuzumab emtansine(T-DM1,Kadcyla)的成功上市,ADCs引起了人们极大的关注。本文综述ADC的分子特征以及组分优化选择,并简单介绍ADC的发展历程。     

抗体药物偶联物及其在恶性血液系统肿瘤治疗中的应用

单克隆抗体靶向治疗是目前临床肿瘤治疗的热点。针对抗体分子大而组织穿透性差以及临床使用剂量大、生产成本高的问题,抗体的小型化和高效性设计已成为抗体药物研发的新趋势。近年来,单抗与细胞毒性药物的结合物被称为抗体药物偶联物(antibody-drug conjugates,ADCs),已加入到抗癌药物的行列中,成为新型的抗体药物而受到广泛关注。泛义的ADC通常由抗体、接头(linker)和效应分子等3部分组成。根据效应分子的不同,可将ADC分为化学免疫偶联物、免疫毒素、放射性免疫偶联物等3类。ADC被内化进入细胞后,通过细胞内的化学和酶解作用释放出细胞毒性物质,细胞毒性物质则通过抑制蛋白合成、解聚微管蛋白或断裂双链DNA等作用而对靶细胞产生杀伤作用。近年来,FDA已经批准2种ADC药物上市,有多种处于II～III期临床试验阶段,取得了显著的临床效果,吸引了越来越多的制药企业争相竞逐。本文介绍ADC的过去和现状,结合临床肿瘤应用中的实际问题,探讨其将来的发展趋势。     

神经毒素的研究与利用

<正> 生物活性天然物质的研究是当代的一个新课题,而动物毒素和其它天然毒素一样又是生物活性天然物质研究中的重要组成部分。生物毒素的研究在过去的二十年中受到各国学者的重视,生物学、医学、生理学和生物化学工作者对此产生了浓厚兴趣,近代研究表明,生物毒素对于人类起着两方面的作用,它可以作为药物起作用,也可以作为毒物起作用。生物毒素对于生物本身来说,所产生的毒素是其最有效的“化学武器”,有的用它来攻击对手,获取食物(象蛇、水母、章鱼);有的用于防御敌害,保卫自身(象有毒植物、蜜蜂     

Development of applicable thiol-linked antibody–drug conjugates with improved stability and therapeutic index

Maleimides are typically applicable for coupling with reactive thiol moieties of antibodies in antibody–drug conjugates (ADCs) via the thiol-Michael click chemistry. Even so, the thiosuccinimide group produced in ADCs is unstable under physiological conditions, which is a unresolved issue in the ADC industry that can cause serious off-target toxicity. Committed to solving the stability defects of traditional thiosuccinimide-containing ADCs, we explored a series of linkers based on the ring-opening hydrolysates of thiosuccinimide. Meanwhile, a type of linkers based on maleamic methyl ester were used to conjugate the popular monomethyl auristatin E to an anti-HER2 antibody to generate the target ADCs, which enhances the stability and do not need to change the structure of the ideal stable metabolite of traditional ADCs. In vivo studies demonstrate that our preferred ADC mil40-12b not only has better efficacy than traditional ADCs but also exhibits better safety parameters in mice. For example, complete tumor regression can still be achieved even when the dose is halved (2.5 mg/kg), and the maximum tolerable dose is increased by 40 mg/kg. This strategy is expected to provide an applicable tool for the construction of thiol-linked ADCs with improved therapeutic index.     

Development and Translational Application of an Integrated,Mechanistic Model of Antibody-Drug Conjugate Pharmacokinetics

Antibody drug conjugates (ADC), in which small molecule cytotoxic agents are non-specifically linked to antibodies, can enable targeted delivery of chemotherapeutics to tumor cells. ADCs are often produced and administered as a mixture of conjugated antibodies with different drug to antibody ratios (DAR) resulting in complex and heterogeneous disposition kinetics. We developed a mechanism-based platform model that can describe and predict the complex pharmacokinetic (PK) behavior of ADCs with protease-cleavable valine-citrulline (VC) linker linked to Monomethylmonomethyl auristatin F/E by incorporating known mechanisms of ADC disposition. The model includes explicit representation of all DAR species; DAR-dependent sequential deconjugation of the drug, resulting in the conversion of higher DAR to lower DAR species; and DAR-dependent antibody/ADC clearance. PK profiles of multiple analytes (total antibody, drug-conjugated antibody, and/or antibody-conjugated drug) for different ADC molecules and targets in rodents and cynomolgus monkeys were used for model development. The integrated cross-species model was successful in capturing the multi-analyte PK profiles after administration of purified ADCs with defined DAR species and ADCs with mixtures of DAR. Human PK predictions for DSTP3086S (anti-STEAP1-vc-MMAE) with the platform model agreed well with PK (total antibody and antibody-conjugated drug concentrations) measurements in the dose-ranging phase I clinical study. The integrated model is applicable to various other ADCs with different formats, conjugated drugs, and linkers, and provides a valuable tool for the exploration of mechanisms governing disposition of ADCs and enables translational predictions.     

The Properties of Cysteine-Conjugated Antibody-Drug Conjugates Are Impacted by the IgG Subclass

Among the numerous antibody-drug conjugate (ADC) clinical candidates, one of the most prevalent types utilizes the interchain cysteines in antibodies to conjugate auristatin via a maleimide-containing linker. In this class of ADCs, there are a paucity of systematic studies characterizing how IgG subclass influences the biophysical properties and in vivo pharmacokinetics of the ADC molecules. In the current investigation, we studied cysteine-conjugated ADCs using a model system consisting of human IgG1, IgG2, and IgG4 antibodies with the same variable region. Our findings identified some unforeseen differences among the three ADCs. Drug conjugation profiling by LC-MS revealed that 50% of inter heavy-light chain disulfide bonds are disrupted to conjugate drugs in IgG1 antibody while only 10% in IgG2 antibody and 20% in IgG4 antibody. The solution behavior of the ADCs was interrogated in concentrating experiments and diffusion interaction parameter measurements. We found that drug conjugation affected the solution property of the three antibodies differently, with the IgG2-based ADC having the most increased propensity to aggregate. Rat PK studies using a sensitive LC-MS-based bioanalytical method showed that the IgG1-based ADC has poor peripheral linker-payload stability while the IgG2- and IgG4-based ADCs are stable. The conjugate stability of the IgG2-based ADC was further confirmed in a cynomolgus monkey PK study. Overall, the IgG2-based ADC exhibited the best PK/conjugate stability but also the most deterioration in stability among the three ADCs. Our findings provide important information and present multifactorial considerations for the selection of IgG subclass during ADC drug discovery when employing stochastic cysteine conjugation.     

治疗晚期或转移性尿路上皮癌的抗体偶联药物:enfortumab vedotin

enfortumab vedotin为一种抗体偶联药物,可与nectin-4结合释放出小分子细胞毒药物单甲基奥瑞他汀E。单甲基奥瑞他汀E具有抗有丝分裂的作用,能作用于微管蛋白抑制肿瘤生长。enfortumab vedotin可用于治疗晚期或转移性尿路上皮癌。常见不良反应有疲劳、外周神经病变、食欲下降、皮疹等。     

Preparation and anti-cancer evaluation of promiximab-MMAE,an anti-CD56 antibody drug conjugate,in small cell lung cancer cell line xenograft models

Antibody-drug conjugates (ADCs) have been successfully applied clinically as target drugs for cancer. In this study, anti-neural cell adhesion molecule also called CD56 antibody-monomethyl auristatin E (MMAE) conjugate named Promiximab-MMAE was prepared by conjugation of microtubule inhibitor MMAE with Promiximab. The average drug-to-antibody ratio (DAR) of Promiximab-MMAE was 3.13 as analysed by liquid chromatography–mass spectrometry/ mass spectrometry (LC-MS/MS). The targeting capacity and affinity kinetics of Promiximab-MMAE were similar to that of Promiximab after being conjugated with MMAE as tested by flow cytometry and biolayer interferometry analysis. Promiximab-MMAE showed effective anti-proliferation on CD56-positive cell lines (NCI-H524, NCI-H526, and NCI-H69), with the half maximal inhibitory concentration (IC50) values of 19.24, 5.23, and 0.32?nmol/L in vitro, respectively. Promiximab-MMAE of 10?mg/kg every three days with a total of three times was administered in vivo. Results showed that the tumour regression was not recrudesced in NCI-H69 and NCI-H526 xenograft mice models till 52 and 56?days. Moreover, body weight and histopathology of the major organs (liver, spleen, heart, lung, and kidney) showed no significant changes after treatment with Promiximab-MMAE. In conclusion, Promiximab-MMAE is a potential candidate for the treatment of CD56 positive small cell lung cancer.     

抗体偶联药物合成过程中定点偶联技术的前沿进展

抗体偶联药物(antibody-drug conjugate,ADC)作为一种用于治疗肿瘤的新型药物,在过去的几十年已获长足进步。然而,由于ADC的异质性,它在临床治疗中仍然面临着各种问题和挑战。因此,定点偶联技术成为ADC药物研究的重要领域,近年来该领域取得了许多突破性进展,这赋予了ADC更优异的性能。本文系统全面地概述了ADC定点偶联技术领域的前沿进展,包括赖氨酸、半胱氨酸、低丰度氨基酸、聚糖定点偶联技术以及非天然氨基酸掺入、酶介导定点偶联技术等7个大类,详细介绍了THIOMAB技术、关键点定向修饰技术等21种经典和新兴的ADC偶联技术,以期为下一代ADC开发提供参考。     

Preclinical and clinical pharmacokinetic/pharmacodynamic considerations for antibody–drug conjugates

Antibody-drug conjugates (ADCs) represent a promising therapeutic modality for the clinical management of cancer. Here we discuss the clinical pharmacology and safety of ADCs that are either approved or in late stages of clinical development. We have taken examples of ADCs employing either DNA damaging payloads (such as calicheamicin) or tubulin depolymerizing agents (such as auristatins and maytansinoids) to discuss the impact of dose and dosage intervals on pharmacokinetics/pharmacodynamics (PK/PD) and safety of ADCs. We also discuss the development of PK/PD models that were validated using preclinical and clinical data from two approved ADCs (ado-trastuzumab emtansine (T-DM1, Kadcyla?) and brentuximab vedotin (SGN-35, Adcetris?). These models could be used to predict clinical efficacious doses of ADCs.     

Duocarmycin-based antibody–drug conjugates as an emerging biotherapeutic entity for targeted cancer therapy: Pharmaceutical strategy and clinical progress

Duocarmycins are a class of DNA minor-groove-binding alkylating molecules. For the past decade, various duocarmycin analogues have been used as payloads in the development of antibody–drug conjugates (ADCs). Currently, more than 15 duocarmycin-based ADCs have been studied preclinically, and some of them such as SYD985 have been granted Fast-Track Designation status. Nevertheless, progress in duocarmycin-based ADCs also faces challenges, with setbacks including the termination of BMS-936561/MDX-1203. In this review, we discuss issues associated with the efficacy, pharmacokinetic profile, and toxicological activity of these biotherapeutics. Furthermore, we summarize the latest advances in duocarmycin-based ADCs that have different target specificities and linker chemistries. Evidence from preclinical and clinical studies has indicated that duocarmycin-based ADCs are promising biotherapeutics for oncological application in the future.     

Pharmacokinetic Considerations for Antibody Drug Conjugates

Antibody drug conjugates (ADCs) are a class of therapeutics that combine the target specificity of an antibody with the potency of a chemotherapeutic. This therapeutic strategy can significantly expand the therapeutic index of a chemotherapeutic by minimizing the systemic exposure and associated toxicity of the chemotherapeutic agent, while simultaneously maximizing the delivery of the chemotherapeutic to the target. The abundance of antibody targets, coupled with advances in antibody engineering, conjugation chemistry, and examples of early clinical success, have stimulated interest in developing ADCs. However, developing and optimizing the highly complex components of ADCs remain challenging. Understanding the pharmacokinetics (PK) and consequently the pharmacokinetic-pharmacodynamic (PKPD) properties of ADCs is critical for their successful development. This review discusses the PK properties of ADCs, with a focus on ADC-specific characteristics, including molecular heterogeneity, in vivo processing, and the implications of multiple analytes. The disposition of ADCs and the utility of PKPD modeling are discussed in the context of providing guidance to assist in the successful development of these complex molecules.