更新于：2024-05-01

BTX

肉毒杆菌毒素

更新于：2024-05-01

基本信息

别名

肉毒杆菌毒素、BoNT

简介

Responsible for host epithelial cell transcytosis, host nerve cell targeting and translocation of light chain (LC) into host cytosol. Composed of 3 subdomains; the translocation domain (TD), and N-terminus and C-terminus of the receptor-binding domain (RBD). The N-terminus of the TD wraps an extended belt around the perimeter of the LC; it does not seem to protect the active site, but might prevent premature LC dissociation from the translocation channel and protect toxin prior to translocation (PubMed:10932256, PubMed:17167418). Has 2 coreceptors; complex gangliosides found primarily on neural tissue and host synaptotagmin-1 and -2 (SYT1 and SYT2) which bind simultaneously to adjacent but separate sites at the tip of the HC (PubMed:8144634, PubMed:17185412, PubMed:17167421, PubMed:17167418, PubMed:23807078). HC alone partially prevents uptake of whole toxin by neural cells, and delays paralysis onset by 160% (PubMed:10413679). Binding probably positions the TD for integration into the synaptic vesicle membrane (PubMed:17167418, PubMed:23807078). The HC forms channels at low pH that mediate transport of the light chain (LC) from the endocytic vesicle to the cytosol (PubMed:3856850). Binds gangliosides GD1b and GT1b (PubMed:10413679, PubMed:14731268). Gangliosides are not only a coreceptor, but also required for uptake into nerve cells (PubMed:21925111, PubMed:17167418). HC alone binds to host receptor proteins SYT1 and SYT2 (PubMed:14504267, PubMed:15123599, PubMed:17185412, PubMed:19650874). Interaction with SYT1 protein does not require SYT1 glycosylation (PubMed:19476346). The HC C-terminus (approximately residues 1079-1291) interacts with host SYT2 (PubMed:15123599, PubMed:17167421, PubMed:17167418, PubMed:23807078). Has higher affinity for SYT2 than SYT1 (PubMed:17185412, PubMed:17167421). Significantly decreases uptake and toxicity of whole BoNT/B and BoNT/G (PubMed:19650874). Botulinum toxin causes flaccid paralysis by inhibiting neurotransmitter (acetylcholine) release from the presynaptic membranes of nerve terminals of the eukaryotic host skeletal and autonomic nervous system, with frequent heart or respiratory failure. Precursor of botulinum neurotoxin B which has 2 coreceptors; complex polysialylated gangliosides found on neural tissue and specific membrane-anchored proteins found in synaptic vesicles (PubMed:17185412, PubMed:17167421, PubMed:17167418, PubMed:23807078). Receptor proteins are exposed on host presynaptic cell membrane during neurotransmitter release, when the toxin heavy chain (HC) binds to them (PubMed:14504267). Upon synaptic vesicle recycling the toxin is taken up via the endocytic pathway (PubMed:14504267). When the pH of the toxin-containing endosome drops a structural rearrangement occurs so that the N-terminus of the HC forms pores that allows the light chain (LC) to translocate into the cytosol (PubMed:3856850). Once in the cytosol the disulfide bond linking the 2 subunits is reduced and LC cleaves its target protein on synaptic vesicles, preventing their fusion with the cytoplasmic membrane and thus neurotransmitter release. Binds to host peripheral neuronal presynaptic membranes via synaptotagmins 1 and 2 (SYT1 and SYT2) (PubMed:8144634, PubMed:14504267). Toxin binds to the membrane proximal extra-cytoplasmic region of host SYT1 and SYT2 that is transiently exposed outside of cells during exocytosis; exogenous gangliosides enhance binding and subsequent uptake of toxin into host cells (PubMed:14504267, PubMed:15123599). Toxin uptake into neural cells requires stimulation (incubation with K(+) to stimulate SYT protein receptor exposure); subsequently the toxin colocalizes with its receptor in host cells with a concomitant decrease in target protein (synaptobrevin-2/VAMP2) immunoreactivity (PubMed:14504267). Toxin uptake can be blocked by the appropriate synaptotagmin protein fragments and gangliosides in cell culture and in mice (PubMed:14504267, PubMed:15123599). BoNT/B is a 'coincidence detector'; it requires simultaneous binding to coreceptor GT1b and low pH to transform into a membrane-bound, oligomeric channel (PubMed:21925111, PubMed:22720883). Whole toxin only has protease activity after reduction which releases LC (PubMed:1331807, PubMed:7803399). Has proteolytic activity (PubMed:1331807). After translocation into the eukaryotic host cytosol, inhibits neurotransmitter release by acting as a zinc endopeptidase that cleaves the '76-Gln-|-Phe-77' bond of synaptobrevin-2/VAMP2, blocking neurotransmitter release (PubMed:1331807, PubMed:7803399). In vitro the LC only has protease activity after reduction (PubMed:1331807, PubMed:7803399).

关联

靶点

BTX

作用机制

BTX抑制剂

在研机构

Emergent BioSolutions Canada, Inc. [+1]

原研机构

Emergent BioSolutions Canada, Inc.

在研适应症

肉毒中毒

非在研适应症-

最高研发阶段批准上市

首次获批国家/地区

美国

首次获批日期2013-03-22

Botulism Immune Globulin(Human)(California Department of Public Health)

靶点

BTX

作用机制

BTX抑制剂

在研机构

California Department of Health Services [+1]

原研机构

California Department of Public Health

在研适应症

肉毒中毒

非在研适应症-

最高研发阶段批准上市

首次获批国家/地区

美国

首次获批日期2003-10-23

XOMA-3AB

靶点

BTX

作用机制

BTX抑制剂

在研机构

University of California [+3]

原研机构

University of California

在研适应症

中毒

非在研适应症

肉毒中毒

最高研发阶段临床1期

首次获批国家/地区-

首次获批日期1800-01-20

项与 BTX 相关的临床试验

NCT06112834 / Not yet recruiting临床2期IIT

Tolerability and Immunogenicity of a Single 40-µg Dose of Recombinant Botulinum Vaccine A/B (rBV A/B) for the Production of BabyBIG® in Volunteers With Existing Botulinum Immunity

This Phase 2, open-label, uncontrolled study designed to evaluate safety, tolerability, and immunogenicity of a single dose of rBV A/B in healthy participants previously immunized with pentavalent botulinum toxoid (or pentavalent botulinum toxoid and rBV A/B) for occupational protection will be conducted to collect source plasma for potential use in the production of BabyBIG and to evaluate safety and immunogenicity of the vaccine in these participants over a 12-week period, with a follow-up safety assessment at 6 months.

开始日期2024-06-01

申办/合作机构

California Department of Public Health

NCT04212676 / Unknown statusN/AIIT

The Effect of Body Awareness Therapy on Postural Stability, Balance and Fear of Falling in Patients With COPD

Chronic obstructive pulmonary disease (COPD) is one of the serious diseases with a high prevalence and mortality, which adversely affects the quality of life, and is expected to rank third in the global burden of disease in 2020. Although the primary pathophysiology of the disease is pulmonary, it is emphasized that extrapulmonary involvement and comorbid conditions adversely affect the severity and prognosis of the disease. In the treatment guidelines for COPD, extrapulmonary systems and symptoms should also be evaluated. In this context, the number of studies on the effects of postural stability, balance and fall has increased recently, especially in COPD patients. Although the efficacy of pulmonary rehabilitation (PR) in COPD is well defined, it provides minimal gains in postural control and balance. Alternative therapies are needed to improve postural stability, balance and fall in COPD patients.
Body Awareness Therapy (BAQ) is an alternative method developed by French exercise instructor and psychotherapist Jacques Dropsy in the early 1970s following the emergence of the concept of body awareness, adapted to rehabilitation programs by Swedish and Norwegian physiotherapists. Traditional physiotherapy methods are the basis of BAQ. In the treatment, sensory stimulation and movement quality, rhythm, coordination, breathing, relaxation, balance, coordination and proprioceptive exercises give more space. In the literature, BAQ decreases pain, fatigue, eating and sleep problems in chronic musculoskeletal or rheumatic pain, coronary artery disease and neurological patient groups. It is seen to increase the quality of exercise, coordination, balance, postural control, quality of life and the integration between mind-body. Movement awareness and mind-body-behavior interaction developed in BAQ can help regulate emotional, mental, social and behavioral factors that affect health. In addition to improving coping skills and cognitive behaviors among COPD patients, it can contribute to positive gains in better movement, respiratory control and balance. The aim of this study is to investigate the effect of BAQ, which is integrated into 8-week pulmonary rehabilitation sessions, on postural stability, balance and fall conditions.

开始日期2020-02-01

申办/合作机构

Marmara University

NCT03603665 / Completed临床1期IIT

A Phase I, Double-Blind, Dose Escalation Study to Evaluate the Safety and Pharmacokinetics of NTM-1633 vs Placebo Administered Intravenously in Healthy Adults

This is a Phase I, single-center, double-blind, placebo-controlled dose escalation trial of three dose cohorts (A: 0.033 mg/kg, B: 0.165 mg/kg, and C: 0.33 mg/kg). The purpose of this study is to evaluate the safety and tolerability of NTM-1633 in healthy adults. This is a first-in-human study consisting of three cohorts of eight subjects each. Dosing for each cohort is as follows: Two sentinel subjects will be administered a single 1-hour infusion (one NTM-1633, one placebo). No more than two subjects per day thereafter (at least 24 hrs will elapse between the dosing of each two subjects) will be dosed in the same manner until all subjects are dosed. Dose escalation will not occur until safety data through Day 8 is reviewed by the Safety Review Committee (SRC). Objective dose-escalation criteria and safety evaluations will be utilized. The study duration will be for approximately 8 months. Subjects in Cohort A will participate for approximately 17 weeks and Subjects in Cohorts B and C will participate approximately 21 weeks. Primary Objective: To assess the safety and tolerability of escalating doses of NTM-1633 administered intravenously in healthy adults.

开始日期2018-09-25

申办/合作机构

National Institute of Allergy & Infectious Diseases

100 项与 BTX 相关的临床结果

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100 项与 BTX 相关的转化医学

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0 项与 BTX 相关的专利（医药）

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1,083

项与 BTX 相关的文献（医药）

2024-04-01·Clinical and experimental pharmacology & physiology

Synergic actions of botulinum neurotoxin A and oxaliplatin on colorectal tumour cell death through the upregulation of TRPM2 channel-mediated oxidative stress.

Article

作者: Sıdıka Demir ; İpek Duman ; Mustafa Nazıroğlu

Botulinum neurotoxin A (BoNT) is being shown to have anticancer action as a potential adjuvant treatment. The transient receptor potential (TRP) melastatin 2 (TRPM2) stimulator action of BoNT was reported in glioblastoma cells, but not in colorectal cancer (HT29) cells. By activating TRPM2, we evaluated the impacts of BoNT and oxaliplatin (OXA) incubations on oxidant and apoptotic values within the HT29 cells. Control, BoNT (5 IU for 24 h), OXA (50 μM for 24 h) and their combinations were induced. We found that TRPM2 protein is upregulated and mediates enhanced BoNT and OXA-induced Ca²⁺ entry in cells as compared to control cells. The increase of free reactive oxygen species (ROS), but the decrease of glutathione is the main ROS responsible for TRPM2 activation on H29 exposure to oxidative stress. BoNT and OXA-mediated Ca²⁺ entry through TRPM2 stimulation in response to H₂ O₂ results in mitochondrial Ca²⁺ overload, followed by mitochondrial membrane depolarization, apoptosis and caspase-3/-8/-9, although they were diminished in the TRPM2 antagonist groups (N-(p-amylcinnamoyl)anthranilic acid and carvacrol). In conclusion, by increasing the susceptibility of HT29 tumour cells to oxidative stress and apoptosis, the combined administration of BoNT and OXA via the targeting of TRPM2 may offer a different approach to kill the tumour cells.

2024-02-21·Microbial pathogenesis

Evaluation of long-term immune response in cattle to botulism using a recombinant E. coli bacterin formulated with Montanide™ ISA 50 and aluminum hydroxide adjuvants.

Article

作者: Clovis Moreira ; Rafael R Rodrigues ; Carlos E P da Cunha ; Rafael A Donassolo ; Marcos R A Ferreira ; Paula F Finger ; Hanna G S Oliveira ; Karoline P da Cruz ; Ângela N Moreira ; Felipe M Salvarani ; Fabricio R Conceição

Botulism is a severe disease caused by potent botulinum neurotoxins (BoNTs) produced by Clostridium botulinum. This disease is associated with high-lethality outbreaks in cattle, which have been linked to the ingestion of preformed BoNT serotypes C and D, emphasizing the need for effective vaccines. The potency of current commercial toxoids (formaldehyde-inactivated BoNTs) is assured through tests in guinea pigs according to government regulatory guidelines, but their short-term immunity raises concerns. Recombinant vaccines containing the receptor-binding domain have demonstrated potential for eliciting robust protective immunity. Previous studies have demonstrated the safety and effectiveness of recombinant E. coli bacterin, eliciting high titers of neutralizing antibodies against C. botulinum and C. perfringens in target animal species. In this study, neutralizing antibody titers in cattle and the long-term immune response against BoNT/C and D were used to assess the efficacy of the oil-based adjuvant compared with that of the aluminum hydroxide adjuvant in cattle. The vaccine formulation containing Montanide™ ISA 50 yielded significantly higher titers of neutralizing antibody against BoNT/C and D (8.64 IU/mL and 9.6 IU/mL, respectively) and induced an immune response that lasted longer than the response induced by aluminum, extending between 30 and 60 days. This approach represents a straightforward, cost-effective strategy for recombinant E. coli bacterin, enhancing both the magnitude and duration of the immune response to botulism.

2024-02-13·mBio

Botulinum neurotoxin X lacks potency in mice and in human neurons.

Article

作者: Brieana M Gregg ; Takuhiro Matsumura ; Travis G Wentz ; William H Tepp ; Marite Bradshaw ; Pål Stenmark ; Eric A Johnson ; Yukako Fujinaga ; Sabine Pellett

Botulinum neurotoxins (BoNTs) are a class of toxins produced by Clostridium botulinum (C. botulinum) and other species of Clostridia. BoNT/X is a putative novel botulinum neurotoxin identified through genome sequencing and capable of SNARE cleavage, but its neurotoxic potential in humans and vertebrates remained unclear. The C. botulinum strain producing BoNT/X, Strain 111, encodes both a plasmid-borne bont/b2 as well as the chromosomal putative bont/x. This study utilized C. botulinum Strain 111 from Japan as well as recombinantly produced full-length BoNT/X to more fully analyze this putative pathogenic toxin. We confirmed production of full-length, catalytically active native BoNT/X by C. botulinum Strain 111, produced as a disulfide-bonded dichain polypeptide similar to other BoNTs. Both the purified native and the recombinant BoNT/X had high enzymatic activity in vitro but displayed very low potency in human-induced pluripotent stem cell-derived neuronal cells and in mice. Intraperitoneal injection of up to 50 µg of native BoNT/X in mice did not result in botulism; however, mild local paralysis was observed after injection of 2 μg into the gastrocnemius muscle. We further demonstrate that the lack of toxicity by BoNT/X is due to inefficient neuronal cell association and entry, which can be rescued by replacing the receptor binding domain of BoNT/X with that of BoNT/A. These data demonstrate that BoNT/X is not a potent vertebrate neurotoxin like the classical seven serotypes of BoNTs.IMPORTANCEThe family of botulinum neurotoxins comprises the most potent toxins known to humankind. New members of this family of protein toxins as well as more distantly related homologs are being identified. The discovery of BoNT/X via bioinformatic screen in 2017 as a putative new BoNT serotype raised concern about its potential as a pathogenic agent with no available countermeasures. This study for the first time assessed both recombinantly produced and native purified BoNT/X for its vertebrate neurotoxicity.

项与 BTX 相关的新闻（医药）

2023-05-11

·动脉网

成立半年获“未来医疗100强”两类奖项，铂桐医疗以数字医疗赋能医联体闭环疼痛管理

2023年5月6日，“2023未来医疗100强”榜单发布。作为数字医疗领域的优秀企业，铂桐医疗荣获“澎橙奖·年度潜力企业”和价值领域奖。铂桐医疗是国内率先以“癌痛”为切入点的疼痛管理平台，以智能科技为驱动、数据交互为基础、智能算法为核心，赋能医疗机构，闭环解决疼痛。成立不到一年，铂桐医疗打造了软硬件结合的产品矩阵，首创数字医疗赋能的整体疼痛解决方案，核心产品已覆盖全国100多家医疗机构，其数据引擎已积累超过5万例数据。铂桐医疗持续深耕癌症疼痛管理赛道，打造了国内疼痛领域领先的管理平台。构建起从评估、诊疗到管理的服务闭环在5月5日下午举办的数字疗法产业创新实践论坛上，铂桐医疗创始人王杰军教授提到，经过过去10年社会各界的努力，我国总体恶性肿瘤的5年生存率从30.9%提升到40.5%。随着肿瘤总体生存率的提高，肿瘤防控也逐步进入到慢病化管理时代，在持续提高治疗水平的同时，肿瘤患者的生存质量也得到越来越多的关注。其中，“癌痛”作为肿瘤患者最常见的症状之一，严重影响着患者生活质量。王杰军教授在大会上发表主题演讲及圆桌论坛《中国疼痛防控与健康促进战略蓝皮书：中国疼痛医学发展报告（2020）》指出，“我国慢性疼痛患者超过3亿人，且每年以1000万-2000万速度在快速增长，治疗上整体花费约5000亿元。”数据的背后，是疼痛患者及其家庭，乃至全社会承担的巨大压力。面对严峻挑战，政策端明确将在国内推广和执行把“慢性疼痛”“慢性癌痛”等列入疾病诊断的ICD-11的疾病分类系统，为患者收治、医疗质量控制以及医保支付都提供了新契机。铂桐医疗则从产业端发力，致力于打造领先的疼痛管理平台，提高医务人员对肿瘤治疗过程中的疼痛重要性的认知，以及为医务人员提供可执行的标准、可使用的技术工具。已实现B端商业化，将在2023年启动大规模市场拓展BTS （6D疼痛评估系统）是铂桐医疗的核心产品之一。其不仅将原本临床上的多个测试整合起来，而且加入了独有算法，形成一个系统的、多维度的“Total Pain”综合判断，与传统评估问卷BPI相比，BTS评估填写时间更短，受试者使用更方便且更受喜欢；在爆发痛和神经病理痛的预测方面，BTS的准确率均在90%以上。据悉，铂桐医疗预计在2023年发布BTS疼痛评估智能机器人，BTS的大规模临床研究数据即将发表，关于疼痛危象的文章也即将发布，值得期待。铂桐医疗合伙人叶蕾女士曾担任吴阶平医学基金会区域医疗协作体执行秘书，并成功入榜2022年“科创中国”青年创业榜单-长三角G60科创走廊U30，任中国基本建设优化研究会研究员，多年深耕医疗市场领域。铂桐医疗合伙人叶蕾女士她表示，铂桐医疗在B端服务方面已成功实现商业化；同时铂桐医疗在医疗服务商业模式上也做出了成功的探索，通过CPDP医联体实现癌痛质量控制，将产品、系统、设备落地到医疗机构，通过纵向深耕及横向拓展，让铂桐医疗的产品和服务落地更多医院、惠及更多患者，2023年Q3将启动PICU试点建设。身处一线，叶蕾女士对数字医疗行业变化有着清晰感知。她分享到，肿瘤诊疗已从疾病治疗向全生命周期管理转变，因此基于全病程管理的数字医疗是产业重点探索的方向，铂桐医疗的数字医疗全流程整体解决方案正契合了国家和市场对智能化、智慧化的要求。针对数字医疗当前发展现状，她表示，“数字疗法不是黄昏将至，而是涅槃重生”，大浪淘沙之下，经得起市场检验的价值工具始终会被留下。叶蕾女士还介绍到，BTX舒桐多维舒缓仪即将上线，其结合了TENS物理治疗和MBCT心理治疗的方式，是一种综合的疼痛管理方案，具有非成瘾性和非侵入性的优势，安全性高，可以单独使用或联合药物及器械使用，并且可以全面记录疼痛轨迹，跟踪疼痛情况和治疗后变化，更好地评估病情和治疗效果。铂桐医疗的BTX舒桐多维舒缓仪铂桐医疗以数字医疗赋能的整体疼痛解决方案可贯穿病程的诊断、治疗和预后全流程。目前，铂桐医疗的整体疼痛解决方案已形成一个“金字塔”结构。“金字塔”塔底是以BTS多维疼痛评估及支持系统为核心的数字医疗产品矩阵，包含了疼痛诊治的软硬件产品，可延续院外居家疼痛治疗与管理，进行多学科精准诊断，辅助判断病因，并精准、全面评估疼痛状况。铂桐医疗整体解决方案的金字塔结构“金字塔”塔体则是“癌痛规范化能力提升医联体CPDP”项目。这一项目在中国医药卫生事业发展基金会、国家卫健委疼痛质控中心专家、中国临床肿瘤学会支持与康复治疗专家委员会(SCRC)和中国抗癌协会癌症康复与姑息治疗专业委员会(CRPC)的支持下成立，旨在构建癌痛治疗和管理的系统、制度、质控、标准、培训和考核体系，将新理念、新技术和新模式赋能各级医疗机构进行线下落地。“金字塔”塔尖则是疼痛ICU（PAINICU）病房，由镇痛体征检测设备、疼痛评估机器人进行患者生命体征参数收集，经疼痛管理系统PMS、疼痛监测系统PICUS进行数据分析后，输出规范化治疗方案，能够安全、有效地解决疼痛危象、难治性癌痛等难题。除了技术和应用场景的探索，铂桐医疗也构建了创新商业和管理模式——哑铃模式：一端是医疗服务板块；另一端是针对医生群体的培训和临床研究板块；由数据交互管理平台连接，即两端的数据沉淀在平台上，再利用平台数据丰富和升级产品，反馈给两端业务。铂桐医疗的哑铃模式在医疗服务端，铂桐医疗首先利用数字医疗平台产品BTS进行患者评估，基于评估结果建议患者前往线下医疗服务点进行相应治疗；治疗完成后，再通过数字医疗产品BTX进行长期管理。在培训和研究板块，铂桐医疗着力打造疼痛综合管理监测网（CPain），联合医疗机构为医生提供培训教育、进行疼痛质控和真实世界研究等服务。在产品方面，铂桐医疗已经构建起从评估、诊疗到管理的服务闭环。其全流程疼痛管理平台整合了BTS（6D多维疼痛评估系统）、BTC（癌痛多学科咨询系统）、BTX（舒桐多维舒缓仪）。基于此，铂桐医疗还建立了疼痛治疗的标准化临床路径，开发了疼痛管理系统（PMS）、院内疼痛监测系统（PICUS），此外，基于癌痛的大模型(CPM Cancer Pain Foundation Model)已在训练中，帮助各级医疗机构更好地进行同质化的患者疼痛管理。近期推荐声明：动脉网所刊载内容之知识产权为动脉网及相关权利人专属所有或持有。未经许可，禁止进行转载、摘编、复制及建立镜像等任何使用。动脉网，未来医疗服务平台

临床研究

2023-05-07

·药时代

CRBN配体的作用和最新进展

近年来，CRBN配体逐渐成为一个非常流行的E3连接酶配体，不仅可以用作E3连接酶配体来设计合成PROTACs，也可以用来设计分子胶降解剂，在PROTACs和分子胶领域中起着非常重要的作用。PROTACs最常用的E3连接酶是VHL和CRBN，而基于CRBN的PROTACs相对基于VHL的PROTACs来说在口服吸收方面处于更合适的化学空间，多个基于CRBN的PROTACs进入临床研究，包括最著名的两个化合物ARV-110和ARV-471，其中ARV-471已经进入三期临床。目前PROTACs和分子胶主要使用的CRBN配体仍然是免疫调节抑制剂，如来那度胺（Lenalidomide），沙利度胺（Thalidomide）和泊马度胺（Pomalidomide）。但是这些化合物都会存在一些缺陷，如易消旋和易降解neosubstrate等，所以人们一直在开发新型的CRBN配体。靶向蛋白质降解剂靶向蛋白质降解剂，包括分子胶和异型双功能降解剂如蛋白水解靶向嵌合体（PROTACs），是一类快速发展的药物，利用内源性蛋白质降解过程来靶向以前“不可治疗”的蛋白。分子胶与PROTACs具有不同的特性。分子胶是一种小分子，它们与各种难以预测的靶蛋白相互作用，通过诱导和增强两种蛋白质的相互作用显示出不同的生物活性，否则两种蛋白质之间不会显示出内在的亲和力。PROTACs是由两个部分组成的二价分子，一个与靶标蛋白（POI）结合，另一个与E3连接酶结合，通过连接子连接（图1）[1]。图1. PROTACs和分子胶区别但是分子胶和PROTACs也有相似性，它们都通过E3连接酶使蛋白降解，PROTACs最常用的E3连接酶是VHL和CRBN，而基于CRBN的PROTACs在口服吸收方面处于更合适的化学空间，它们的MW可以降至700以下，并且具有合理的药物亲脂性和降低的HBD/nRotB数量（图2）[2]。目前为止发现的分子胶涉及的E3连接酶都是CRBN，所以CRBN配体逐渐成为一个非常流行的E3连接酶配体。图2. E3连接酶配体根据法则5（Ro5）进行比较分子胶分子胶是目前唯一的获批上市的降解剂药物，目前被批准上市的分子胶药物有来那度胺（Lenalidomide），沙利度胺（Thalidomide）和泊马度胺（Pomalidomide）。它们被称为cereblon（CRBN）E3连接酶调节剂（CELMoD）或者免疫调节药物（IMiDs），与CRBN结合，CRBN与 DDB1 (damaged DNA binding protein 1)、Cul4A (Cullin 4A)、ROC1 形成 E3 泛素连接酶复合物（CRL4），CRBN作为底物受体并结合一些蛋白质，促进其泛素化和蛋白酶体依赖性蛋白水解，如CK1-a和Ikaros (IKZF 1)/Aiolos (IKZF 3)等（图3）[3]。图3. 分子胶的降解机制除了已上市的三种药物之外，还有多种进入临床研究，如临床II期的CC-90009，CC-92480和CFT-7455等，具体见图4。图4. 进入临床和上市的分子胶基于CRBN的PROTACsPROTAC是近几年研究非常火热的一门新兴领域，基于CRBN的PROTACs通过招募CRBN复合物靠近靶标蛋白，使靶标蛋白多泛素化，从而被蛋白酶体降解（图5）。图5. 基于CRBN的PROTAC dBET1的结构与作用机制多个基于CRBN配体的PROTACs已经进入临床研究，包括最著名的两个化合物ARV-110和ARV-471，其中ARV-471已经进入三期临床（图6）。图6. ARV-110和ARV-471的结构新型CRBN配体目前PROTACs和分子胶主要使用的CRBN配体仍然是免疫调节抑制剂，如来那度胺，沙利度胺和泊马度胺。但是这些化合物都会存在一些缺陷，如易消旋和易降解neosubstrate等，所以后续人们也研发了一些新型的CRBN配体。最新的AACR会议上，已经有一批公司使用新型CRBN配体，包括Arvinas公司的第二代AR降解剂ARV-766，C4公司的BRD9 降解剂CFT8634和BRAF V600E降解剂CFT1946，以及Kymera的IRAK4降解剂KT474（图7）。图7. 基于新型CRBN配体的PROTACCC-122（avadomide）也具有抗癌和免疫调节活性。有两个课题组分别采用了CC-122的类似物用于PROTACs的设计中，如图8所示，Nurix公司在他们的专利中（WO 2021113557）发表了一类BTX降解剂，另外也有一个韩国课题组也将他们研发的CRBN配体用在BRD4的降解上，设计了化合物TD-428。在前列腺癌细胞22Rv1中可以有效地降低BET蛋白，下调C-MYC，抑制细胞增殖[4]。图8. 基于CC-122类似物的PROTACs美国圣裘德儿童研究医院（St. Jude Children’s Research Hospital）在国际期刊Angew. Chem.和ACS Med. Chem. Lett.报道了他们的新型CRBN 配体Phenyl-Glutarimides（PG），可以显著提高化学稳定性而不影响CRBN的结合活性。并且将PG与BRD4的小分子抑制剂结合设计了PROTACs。Phenyl glutarimide可以作为一个备选的CRBN 配体，它具有更高的配体效率，显著提高化学稳定性，细胞活性和容易合成等优点。把它作为E3配体合成的BET PROTACs在MV4-11和HD-MB03细胞系中具有很好的降解活性，其中最优化合物4c在MV4-11细胞系中IC50 = 3 pM, DC50 = 0.87 nM (D max = 99%)[5]。随后该课题组又运用这个配体研发出一种JAK2/3 PROTACs，与经典的IMiDs相比，SJ10542可以降低对GSPT1的降解活性，减少脱靶效应（图9）[6]。图9. 化合物4c和SJ10542的结构天津大学发表了发现了一类新型CRBN配体，在苯环与glutarimide之间用酰胺键相连。通过TR-FRET实验测试了这些化合物对CRBN的结合能力，这3个化合物（YJ1b，YJ2c，YJ2e）均表现出了较好的结合能力[7]。除此之外，Dana-Farber 肿瘤研究所的Nathanael Gray小组在2篇专利（WO 2020/006233 A1, WO 2020/006265）中也报道了类似的结构，并且还将其用在溴结构功能域降解剂上（图10）。图10. 化合物YJ1b，YJ2c，YJ2e和BET PROTAC的结构王少萌课题组也发表了一系列三元环的新型CRBN配体，并将它们运用到多个靶点降解剂上。如AR降解剂495（WO 2021/055756），ER降解剂E453（WO 2022/187588），均具有较好地活性（图11）。图11. AR降解剂495和ER降解剂E453的结构小结靶向蛋白质降解剂，包括分子胶和异型双功能降解剂如PROTACs，是一类快速发展的药物，利用内源性蛋白质降解过程来靶向以前“不可治疗”的蛋白质，以及以新的方式确定药物靶向。PROTACs作为一个热门领域，近几年受到投资者和学术界广泛关注，除了PROTACs之外，也有很多其它相关的技术被发现，如LYTAC，CHAMP，ATAC，ATTEC，单价蛋白降解剂和AnDC等。PROTAC领域进展最快的是Arvinas的ARV-110和ARV-471，都是基于CRBN的PROTACs。目前为止发现的分子胶涉及的E3连接酶都是CRBN，所以CRBN配体逐渐成为一个非常流行的E3连接酶配体，关于CRBN的优化一直在进行，希望同时可以改善成药性和安全性。参考文献：1.Janet M. Sasso, Rumiana Tenchov, DaSheng Wang, Linda S. Johnson, Xinmei Wang, and Qiongqiong Angela Zhou, Molecular Glues: The Adhesive Connecting Targeted Protein Degradation to the Clinic, Biochemistry 2023, 62, 601−6232.Nicolas Guedeney, Marie Cornu, Florian Schwalen, Charline Kieffer, Anne Sophie Voisin-Chiret, PROTAC technology: A new drug design for chemical biology with many challenges in drug discovery, Drug Discovery Today d Volume 28, Number 1 d January 20233.Junichi Yamamoto, Takumi Ito, Yuki Yamaguchi and Hiroshi Handa, Discovery of CRBN as a target of thalidomide: a breakthrough for progress in the development of protein degraders, Chem. Soc. Rev., 2022, 51, 62344.Kim, S. A.; Go, A.; Jo, S.-H.; Park, S. J.; Jeon, Y. U.; Kim, J. E.; Lee, H. K.; Park, C. H.; Lee, C.-O.; Park, S. G.; Kim, P.; Park, B. C.; Cho, S. Y.; Kim, S.; Ha, J. D.; Kim, J.-H.; Hwang, J. Y., A novel cereblon modulator for targeted protein degradation. European Journal of Medicinal Chemistry 2019, 166, 65-74.5.Min, J.; Mayasundari, A.; Keramatnia, F.; Jonchere, B.; Yang, S. W.; Jarusiewicz, J.; Actis, M.; Das, S.; Young, B.; Slavish, J.; Yang, L.; Li, Y.; Fu, X.; Garrett, S. H.; Yun, M.-K.; Li, Z.; Nithianantham, S.; Chai, S.; Chen, T.; Shelat, A.; Lee, R. E.; Nishiguchi, G.; White, S. W.; Roussel, M. F.; Potts, P. R.; Fischer, M.; Rankovic, Z., Phenyl-Glutarimides: Alternative Cereblon Binders for the Design of PROTACs. Angewandte Chemie International Edition 2021, 60 (51), 26663-26670.6.Alcock, L. J.; Chang, Y.; Jarusiewicz, J. A.; Actis, M.; Nithianantham, S.; Mayasundari, A.; Min, J.; Maxwell, D.; Hunt, J.; Smart, B.; Yang, J. J.; Nishiguchi, G.; Fischer, M.; Mullighan, C. G.; Rankovic, Z., Development of Potent and Selective Janus Kinase 2/3 Directing PG–PROTACs. ACS Medicinal Chemistry Letters 2022, 13 (3), 475-482.7.Yan, J.; Zheng, Z., Discovery of Highly Potent CRBN Ligands and Insight into Their Binding Mode through Molecular Docking and Molecular Dynamics Simulations. ChemMedChem 2023, 18 (5), e202200573.封面图来源：123rf2023年1月1日至今，~17笔中国新药出海交易横空出世，总金额高达上百亿美元！一时间，喜讯频传，令行业、企业和每一位同药振奋！曾经提出“百靶竞技，百炼创新，百家上市，百药争先”的药时代团队再一次真切感受到：中国新药研发正当时！中国新药出海正当时！中国新药BD正当时！在这个BD如火如荼的好时代里，企业对于BD的要求不断提高，如何与时俱进，学习最新BD知识，掌握最新BD技能，成为摆在每一位BD同药面前的一个实际而迫切的问题。为了帮助企业培养优秀的BD高级人才，为了帮助BD人才成长进步，药时代学苑全力打造创新药BD高级研讨会，致力于成为中国制药界ZUI有实力和活力的学习平台。药时代BD高阶研讨会火热报名中！

蛋白降解靶向嵌合体临床3期临床结果临床2期临床1期

2023-03-09

·药渡Daily

潜力新靶点系列1：CK1靶点药物研发盘点

1 前言蛋白激酶介导的蛋白质磷酸化是细胞中许多信号通路激活和失活的核心，因此，各种蛋白激酶的异常活性往往与许多疾病的发生和进展有关，特别是癌症。相应的，蛋白激酶是最具吸引力的药物抑制靶点之一，超过70种小分子激酶抑制剂已被批准用于临床[1]。在20世纪70年代初，体外酪蛋白磷酸化实验发现酪蛋白激酶1(casein kinase 1，CK1) 家族由不同的成员构成，随后CK1与不同信号分子构成的底物组合被大量发现。CK1家族广泛存在于不同的物种，从酵母到人的许多真核生物中都表达CK1家族成员且它们均具有高度保守性。哺乳动物CK1同种型 (α，β，γ，δ，ε) 及其剪接变体参与细胞不同的生理过程，包括膜运输、昼夜节律、细胞周期进程调控、染色体分离、细胞凋亡和细胞分化等，所有CK1成员的N端和C端非催化结构域显著不同，但是它们的激酶结构域具有高度的保守性。CK1在调控其他生命进程的同时其自身的活动和表达也受到严格调控，从而保证生命体各项活动有序进行。已知CK1调节的机制包括通过抑制性自磷酸化进行磷酸化和(或)被其他细胞蛋白激酶磷酸化，与细胞蛋白质或亚细胞隔离相互作用。CK1家族具有与多种底物结合的部位并且参与调节细胞生命过程，它在Wnt和Hedgehog(Hh)等信号调控、昼夜节律的调节、膜运输、细胞骨架维持、细胞分裂、DNA修复和核定位等过程中均扮演重要角色。CK1的识别基序可以在多种细胞中发现，基于细胞功能的多样性，如在免疫炎症反应和中心体相关的过程、DNA损伤相关的信号转导、昼夜节律调控中，CK1 以不同的形式调控不同的信号通路从而负责调节组织细胞的生长、增殖和凋亡等过程，因此如果CK1家族在信号通路中某一环节功能失调或障碍会导致机体病理过程的发生，如肿瘤形成或神经疾病等。图1 CK1中心体相关功能2 CK1信号通路在过去十年中出现的激酶中，酪蛋白激酶1 (CK1)已被认为是治疗包括癌症在内的多种疾病的有吸引力的靶点。个别CK1亚型显示出高度的结构同源性，这使得鉴定异构体选择性抑制剂具有挑战性，而它们涉及不同的生物过程。CK1激酶在几种细胞通信级联中起着关键作用，例如，CK1δ/ε成员在Wnt/β-catenin信号传导中起着激活作用，而CK1α则可以磷酸化β-catenin并触发其降解，充当Wnt信号通路抑制剂，另外也参与Hedgehog 及Hippo等信号通路的调控。在典型的Wnt/β-catenin信号通路中，所有CK1家族成员都参与其中。然而，这种参与是相当复杂的。在缺乏Wnt配体的情况下，CK1α与轴蛋白、腺瘤性大肠息肉病(APC)和β-catenin(Ser-45)相互作用并磷酸化，从而引发β-catenin被GSK3β进一步磷酸化并随后降解(图2A)。因此细胞质中的β-catenin含量很低，其下游的靶基因转录处于抑制状态。当Wnt配体存在时，GSK3β介导的β-catenin磷酸化被抑制，β-catenin最终不会被降解。该过程会受到CK1α，CK1γ，CK1ε和CK1δ的调节，最终导致β-catenin在细胞质中稳定存在，游离的β-catenin被转运入核，与TCF/LEF复合物等共激活因子相互作用,激活Wnt下游的靶基因转录。图2 CK1与Wnt信号通路[2]3 CK1抑制剂在研情况目前，进入临床的仅有Biotheryx Inc开发的BTX-A51及BTX-1188，且均为CK1α与其他靶点联合的药物，而CK1α也被认为是治疗急性髓系白血病(AML)的一个有吸引力的靶点。适应症方面，仅有辉瑞在开发精神疾病，其他药物均集中于肿瘤适应症的开发。全球首款PI3Kδ/CK1ε抑制剂Umbralisib（UKONIQ）是TG Therapeutics研发并于2021年2月获美国FDA批准上市，Umbralisib曾被美国FDA调查是否会增加患者死亡的风险，于2022年1月27日暂停了两项临床试验，随后被FDA撤回加速批准。4结语虽然CK1抑制剂作为药物靶标具有很大的潜力，但开发可用于体内的选择性CK1抑制剂仍然困难重重。创新药研发，每一关都是九死一生的冒险，即使成功获批上市，后续的临床应用如果出现安全性等问题，依然可能面临撤市的风险。参考文献[1] Attwood, M.M., Fabbro, D.,Sokolov, A.V. et al. Trends in kinase drug discovery: targets, indications andinhibitor design[J]. Nat Rev Drug Discov, 2021, 20, 839-861.[2] Knippschild U , Marc Krüger, Richter J , et al. The CK1 Family: Contribution to Cellular Stress Response and Its Role in Carcinogenesis[J]. Frontiers in Oncology, 2014, 4(4):96.医药咨询业务介绍药渡咨询依托其强大的药学数据库资源以及多学科背景的项目团成员，为国内外医药企业、投资机构、政府和园区提供产品线规划、立项、生产、销售项目尽调、价值评估和BD等各个环节定制化解决方案。1. 为国内外企业完成200多亿的融资和并购进行了CDD和项目价值评估2. 为全球TOP10的MNC中一半以上提供产品战略和BD机会服务3. 为国内外近20家VC或PE提供技术尽职调查服务4. 为国内50多家上市药企行业研究和具体项目转让评估服务5. 为多个园区的项目落地和执行提供可行性论证服务免责声明：“药渡Daily”公众号所转载文章来源于其他公众号平台，主要目的在于分享行业相关知识，传递当前最新资讯。图片、文章版权均属于原作者所有，如有侵权，请及时告知，我们会在24小时内删除相关信息。END👇关注药渡数据媒体矩阵

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