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ROCKVILLE, Md. and SUZHOU, China, April 7, 2024 /PRNewswire/ -- Innovent Biologics, Inc. ("Innovent") (HKEX: 01801), a world-class biopharmaceutical company that develops, manufactures and commercializes high quality medicines for the treatment of oncology, cardiovascular and metabolic, autoimmune, ophthalmology and other major diseases, announces that preclinical data on multiple novel bispecific antibodies as well as antibody-drug-conjugates (ADCs) from its oncology pipeline are presented at the American Association for Cancer Research (AACR) Annual Meeting 2024. Late-Breaking Research: Experimental and Molecular Therapeutics 1 Topic: IBI3001: a potentially first-in-class site-specific glycan-conjugated B7-H3/EGFR bispecific ADC for multiple solid tumors Abstract Number: LB055 Presentation Form: Poster Presentation Time : Sunday Apr 7, 2024 1:30 PM - 5:00 PM Location: Poster Section 53 Presenting Author: Dr. Kaijie He IBI3001 is a potentially first-in-class bispecific ADC against B7-H3 and EGFR that is site-specifically glycan-conjugated using the clinically validated SYNtecanE® platform. IBI3001 has multiple anti-tumor mechanisms of action: (1) enhanced EGFR signaling blockade; (2) EGFR- and B7-H3-aided payload internalization and cytotoxicity; and (3) potent bystander killing effects of ADC. The optimized B7-H3 arm not only enhances the EGFR signaling blockade but also reduces EGFR on-target toxicities. IBI3001 showed strong anti-tumor efficacy in vitro and in vivo across multiple solid tumors and is well tolerated with the therapeutic index at 40. Topic: IBI334, a novel ADCC-enhanced B7-H3/EGFR bispecific antibody, demonstrated potent pre-clinical efficacy in solid tumors Abstract Number: LB056 Presentation Form: Poster Presentation Time : Sunday Apr 7, 2024 1:30 PM - 5:00 PM Location: Poster Section 53 Presenting Author: Dr. Kaijie He IBI334 is an afucosylated bispecific antibody against B7-H3 and EGFR that is constructed using Innovent's proprietary Innobody platform. With the aid of B7-H3, IBI334 showed better tumor growth inhibition in vitro and in vivo than EGFR monoclonal antibody and c-met/EGFR bispecific antibody benchmarks. IBI334 has a favorable safety profile with the highest non-severely toxic dose (HNSTD) in cynomolgus monkeys at 120 mg/kg and a large therapeutic window of > 200 folds. As a promising bispecific antibody against multiple solid tumors, IBI334 is currently under clinical evaluation. Topic: Discovery and preclinical characterization of IBI343, a site-specific glycan-conjugated anti-Claudin18.2 ADC for treating solid tumors Abstract Number: LB057 Presentation Form: Poster Presentation Time : Sunday Apr 7, 2024 1:30 PM - 5:00 PM Location: Poster Section 53 Presenting Author: Dr. Kaijie He IBI343 is a potentially first-in-class anti-Claudin 18.2 ADC that is site-specifically glycan-conjugated to cytotoxin exatecan via Synaffix's GlycoConnect® technology. It demonstrated Claudin 18.2-specific in vitro cytotoxicity on a series of cancer cell lines at varying levels of target expression, and potent in vivo efficacy in multiple xenograft models. The glycan-based conjugation technology leads to enhanced stability of the ADC molecule. IBI343 displayed good safety profile in GLP toxicology study in rhesus monkey and was well tolerated up to 30 mg/kg. IBI343 has favorable pre-clinical efficacy and safety, and it is currently in preparation for Phase 3 clinical trial for Claudin-18.2-positive HER2-negative gastric cancer. Dr. Kaijie He, Vice President of Innovent, stated: "We are pleased that the pre-clinical studies of our novel anti-cancer drugs are accepted for Late-Breaking Research poster presentation at the 2024 AACR conference. This is the result of dedicated work from scientists at Innovent Academy with the aim to tackle cancers with innovative drugs that are more effective and safer. With careful design and optimization, our molecules can achieve favorable therapeutic windows of 40 to more than 200 times. We look forward to their performance in clinical settings and hope that these innovations can eventually benefit cancer patients." Poster Session: Immunology - Single Target and Bispecific Antibodies Topic: A novel TROP2-targeted immune stimulating antibody conjugate (ISAC) with potent anti-tumoral activity and acceptable safety Abstract Number: 2718 Presentation Form: Poster Presentation Time: Monday Apr 8, 2024 1:30 PM - 5:00 PM Location: Poster Section 6 Poster Board Number: 9 Presenting Author: Dr. Huizhong Xiong Immune stimulating antibody conjugates (ISACs) are a unique class of ADC in which antibodies recognizing tumor antigens are conjugated with immune agonists. ISACs target tumor tissue and specifically activate intra-tumoral myeloid cells, unleashing downstream immune response. Like the other immune agonists, balance between efficacy and safety remains a challenge for ISACs. Here we describe a potential first-in-class TROP2 ISAC with rationally selected antibody and TLR7/8 agonist linker-payload. The anti-TROP2 antibody elicited robust ADCP of TROP2+ tumor cells by macrophages. In-vitro, TROP2 ISAC mildly activated myeloid cells only in the presence of TROP2+ tumor cells. In-vivo, the molecule potently suppressed tumor growth in different TROP2+ xenograft tumors, and effectively enhanced killing of an ADC. In terms of safety, the ISAC was tolerated in both WT and hTROP2KI mice, and, importantly, in monkeys. Taken together, our data demonstrate a novel TROP2 ISAC with outstanding efficacy and manageable safety profile, which may benefit patients with TROP2+ tumors. Poster Session: Immunology - Immune Modulation Employing Agonist or Co-Stimulatory Approaches Topic: Tumor targeted-CD28 bispecific antibody with optimized potency, robust anti-tumoral activity and stringent CD3-dependence Abstract Number: 5295 Presentation Form: Poster Presentation Time: Tuesday Apr 9, 2024 1:30 PM - 5:00 PM Location: Poster Section 3 Poster Board Number: 4 Presenting Author: Dr. Huizhong Xiong We reported a rationally screened CD28 agonist antibody and its PSMAxCD28 bispecific format, IAR038. IAR038 has minimal activity in the absence of CD3, even under stringent conditions, different from benchmark antibody in clinical development. It demonstrated moderate activity in vitro in a CD3-dependent and PSMA-dependent manner. Notably, IAR038 elicited superior tumor killing in vivo and combined effectively with anti-PD1 antibody. In addition, it had an improved half-life compared with the Benchmark antibody. These features may translate to a wider therapeutic window and improved safety for CRPC patients. Dr. Huizhong Xiong, Senior Director of Immunology of Innovent, stated: "We keep pushing for deeper understanding and more rational design of agonistic and costimulatory molecules. Our work on tumor targeted TLR7/8 agonist and tumor targeted CD28 antibody demonstrates the capability of our biology-driven drug development to achieve better balance between efficacy and safety, made possible by our advanced technology platforms." About Innovent Innovent is a leading biopharmaceutical company founded in 2011 with the mission to provide high-quality biologics that are affordable to all. The company discovers, develops, manufactures and commercializes innovative medicines that treat some of the most intractable diseases. Its pioneering therapies treat cancer, cardiovascular and metabolic, autoimmune and eye diseases. Innovent has 10 products in the market, 3 new drug applications under the NMPA review, 5 assets in Phase III or pivotal clinical trials and 18 more molecules in early clinical stage. Innovent partners with over 30 global healthcare leaders, including Eli Lilly, Roche, Sanofi, Adimab, Incyte and MD Anderson Cancer Center. Guided by the motto, "Start with Integrity, Succeed through Action," Innovent maintains the highest standard of industry practices and works collaboratively to advance the biopharmaceutical industry so that first-rate pharmaceutical drugs can become widely accessible. For more information, visit , or follow Innovent on Facebook and LinkedIn. Statement: Innovent does not recommend the use of any unapproved drug (s)/indication (s). Forward-looking statement This news release may contain certain forward-looking statements that are, by their nature, subject to significant risks and uncertainties. The words "anticipate", "believe", "estimate", "expect", "intend" and similar expressions, as they relate to Innovent Biologics ("Innovent"), are intended to identify certain of such forward-looking statements. The Company does not intend to update these forward-looking statements regularly. These forward-looking statements are based on the existing beliefs, assumptions, expectations, estimates, projections and understandings of the management of the Company with respect to future events at the time these statements are made. These statements are not a guarantee of future developments and are subject to risks, uncertainties and other factors, some of which are beyond the Company's control and are difficult to predict. Consequently, actual results may differ materially from information contained in the forward-looking statements as a result of future changes or developments in our business, the Company's competitive environment and political, economic, legal and social conditions. The Company, the Directors and the employees of the Company assume (a) no obligation to correct or update the forward-looking statements contained in this site; and (b) no liability in the event that any of the forward-looking statements does not materialise or turn out to be incorrect. SOURCE Innovent Biologics

Presented data support the ongoing clinical assessment of MT-302, the world's first in vivo mRNA CAR drug development candidate Additional updates highlight Myeloid's pioneering work, including a set of novel mRNA CAR constructs for in vivo programming of additional immune cell subsets, including NK and T cells CAMBRIDGE, Mass., April 4, 2024 /PRNewswire/ -- Myeloid Therapeutics, Inc. ("Myeloid"), a clinical stage biotechnology company advancing RNA immunotherapies to conquer cancer, announced that it will provide a preclinical update for MT-302, its novel TROP2-targeting RNA CAR at the 2024 American Association for Cancer Research (AACR) Annual Meeting. MT-302 is currently in a Phase 1 study to assess the therapy's safety and activity in patients with advanced or metastatic epithelial tumors. This advancing study represents the first human trial of any in vivo chimeric antigen receptor (CAR) therapy. Myeloid will also share information on its portfolio of immune cell programming CARs. "We are thrilled to continue driving this first in vivo mRNA CAR program forward," said Chief Executive Officer Daniel Getts, Ph.D. "Myeloid is at the forefront of in vivo immune cell programming. Programming myeloid cells with MT-302 provides significant potential advantages over TROP2-ADCs, in part because MT-302 modified cells can orchestrate a full immune response." Dr. Getts continued, "We are also showcasing the basis for an extensive CAR portfolio, extending in vivo programming to a diverse range of immune cell subsets such as NK and T cells. These data underscore the versatility and broad potential of our RNA immunotherapies in revolutionizing cancer treatment." The posters presented at AACR underlie Myeloid's strategic vision, that LNP-delivered mRNA CARs can selectively activate targeted immune cells, thus offering cancer patients the potential future opportunity of cell therapy-like outcomes without the need for ex vivo autologous cell handling or allogeneic cell engineering and manufacturing. Poster presentation details and abstract highlights include: Date & Time: Monday, April 8, 2024, 9:00 AM – 12:30 PM PT Title: In vivo Immune Cell Programming Using mRNA-LNP Chimeric Antigen Receptors Location: Poster Section 2 Session Category: Immunology Session Title: CAR-NK, NK Engagers, and NK Modulators Poster Board Number: 4 Published Abstract Number: 1321 Myeloid has designed novel CARs that achieve expression and function in targeted immune cell populations. These CARs, by activating innate and adaptive immune responses following the in vivo delivery of LNP-formulated mRNA encoded CARs, are capable of eliciting anti-tumor efficacy against a range of multiple target antigens evaluated. To date, Myeloid has demonstrated CAR activity in human cells, and following systemic mRNA/LNP delivery in mouse and non-human primates. MT302, an in vivo CAR targeting TROP2+ epithelial malignancies (NCT05969041) is undergoing evaluation in a Phase 1 clinical trial, designed to assess the candidate's safety and preliminary efficacy. Title: In vivo Programming of Natural Killer cells and T cells using mRNA delivered Cytotoxic Chimeric Antigen Receptors Location: Poster Section 2 Session Category: Immunology Session Title: CAR-NK, NK Engagers, and NK Modulators Poster Board Number: 2 Published Abstract Number: 1319 Myeloid's portfolio includes a set of novel CARs designed specifically to program NK and T cells. These novel CARs are not active in non-immune cells. The programed NK cells induce cytotoxicity against antigen-expressing tumor cells and trigger the release of cytokines and chemokines, important factors to a full immune response. The company further demonstrated that this approach can be used to design receptors for selective expression on the surface of T cells utilizing CD3𝜀 chain fused with tumor-targeting scFv. About Myeloid Therapeutics Myeloid Therapeutics is a clinical stage immunology company, engineering cutting-edge RNA technology to program immune cells to combat cancer and other deadly diseases. Myeloid is headquartered in Cambridge, MA. For additional information, please visit, and follow us on LinkedIn and X/Twitter. To meet with Myeloid leadership at AACR 2024 please email: partnering@myeloidtx.com Investor Contact Amy Conrad Juniper Point Amy@juniper-point.com

点击上方的 行舟Drug ▲ 添加关注前言迄今为止，与传统的抗癌治疗策略相比，免疫治疗被认为是最有前景的全身性肿瘤治疗方法，其中，单克隆抗体因其特异性靶向分子的能力，已成为癌症治疗中一种关键而有效的治疗方式。然而，由于肿瘤复杂的疾病发病机制，针对单一靶点的单克隆抗体往往不足以表现出足够的治疗效果。因此，针对多个靶点的双特异性抗体（bsAbs）应运而生，它的发展改变了肿瘤免疫治疗的领域。目前，人们正在研究越来越多的针对癌症治疗的不同类型的bsAbs。这些类型包括双靶向抑制剂，其作用于不同水平的肿瘤增殖、血管形成和转移；以及双特异性抗体偶联药物、T细胞结合器、双特异性自然杀伤细胞接合器（NKCE）和先天免疫细胞接合器。其他类型还包括双特异性免疫检查点抑制剂（CPI）、共刺激bsAbs和融合蛋白、具有联合检查点抑制和共刺激特征的bsAbs、在肿瘤微环境（TME）中特异性激活的bsAb，以及将过继T细胞治疗和治疗性抗体相结合的新方法。目前，有300多项临床试验涉及200多种不同的双特异性抗体分子，其中约75%用于治疗实体瘤，25%用于治疗血液系统恶性肿瘤。有10种bsAb药物已被批准用于癌症治疗，其中9种在美国和/或欧洲获得批准，cadonilimab在中国获得批准。到目前为止，临床中开发的很大一部分bsAbs已经处于后期阶段（II期和III期）。另外，可以发现，治疗实体瘤的bsAbs主要由免疫调节剂主导，包括双CPI（约45%）和TCE（约33%），其次是靶向双途径、ICEs和ADC的bsAb。bsAb的发展史BsAbs最初的概念是由AlfredNisonof在20世纪60年代首次提出的。他将两个不同的抗原结合位点结合在一个分子中，并从抗牛γ球蛋白和抗卵清蛋白单价片段的混合物中获得了一个具有双重特异性的F(ab’)2分子。1975年，Köhler和Milstein发明了杂交瘤技术，最终解决了生产单克隆抗体的问题，开启了单克隆抗体治疗的新时代。1983年，Milstein和Cuello开创了quadroma技术，该技术基于分泌Abs混合物的两种不同杂交瘤细胞系的体细胞融合，包括具有双重特异性的鼠IgG形式的bsAb。然而，bsAb的低产率以及难以从密切相关的错配副产物中纯化所需的Ab是一个重大问题。1988年，James Huston和他的同事发明了单链抗体片段（scFv），它最大限度地减少了复性问题，例如不正确的结构域配对或聚集。1996年，Genentech的科学家们利用重组DNA技术发明了knob-into-hole技术，克服了Quadrome技术的局限性。通过在人类IgG的CH3结构域之间的界面突变选定的氨基酸，可以减少IgG重链的错配。这种技术利用更有利的蛋白质相互作用，最终可以形成高达90%的正确双特异性重链配对。随后，随着抗体工程和生物学的进展，bsAb的不同概念和结构正在不断演变。靶向双受体抑制的bsAb许多参与细胞信号传导的细胞表面蛋白，如RTK和相关受体，是基于抗体治疗的有效靶点。尽管靶向一个确定的信号受体的抗体治疗是非常有效的，但疾病相关表型通常由不止一种途径触发。这种冗余允许细胞通过使用其他补偿信号通路，从而耐受药物的生长抑制或细胞毒性诱导。同时调节不同疾病相关信号受体或通路的bsAbs可以减少或克服这一限制。Amivantamab（JNJ-61186372）靶向EGFR和肝细胞生长因子受体（MET），两种受体都能触发非小细胞肺癌（NSCLC）的增殖。因此，阻断两种受体比仅阻断一种途径能够更有效地抑制NSCLC的生长。Amivantamab已被FDA批准用于治疗携带EGFR外显子20插入突变的NSCLC亚型。一项随机III期研究的数据显示，在这部分患者中，与单独化疗相比，Amivantamab联合化疗具有显著优越性。另外一些针对肿瘤不同第二靶点的EGFR的bsAbs也正在临床开发中。例如，petosemtamab（MCLA-158）靶向EGFR和LGR5，LGR5是一种癌症干细胞相关的细胞表面受体。Petosemtamab目前正在包括晚期头颈部鳞状细胞癌在内的实体瘤患者的I/II期试验中进行评估（NCT03526835）。靶向配体受体抑制的bsAbbsAbs可以同时阻断两种不同的配体，或者是配体和受体的组合。VEGF和血管生成素2（ANG2）的双重靶向作用分别阻断VEGFR和血管生成因子1受体（TIE2）的激活，这两种途径涉及血管生成。vanucizumab，一种靶向VEGFA和ANG2的bsAb，在临床前模型中与化疗联合显示出抗肿瘤、抗血管生成和抗转移作用。BI836880是一种三特异性纳米抗体融合蛋白，由三个靶向VEGFA、ANG2和HSA的纳米抗体组成，后者可延长其血清半衰期。目前正在头颈部鳞状细胞癌、NSCLC和其他实体瘤患者的I期研究中进行评估。此外，靶向VEGF可以进一步设计成联合靶向肿瘤细胞上的PD-L1或T细胞上的PD-1，从而将抗血管生成与肿瘤免疫学方法联系起来。例如靶向PD1和VEGF的ivonescimab（AK112），其目前已在中国获批用于。其他bsAbs靶向PDL1和VEGF，包括PM8002，该药物正在NSCLC患者的II/III期研究（NCT05756972）中进行评估。靶向受体激活的bsAb许多抗肿瘤反应是通过激活细胞表面受体介导的，包括通过诱导细胞凋亡的免疫反应或细胞死亡。其中一种方法是靶向递送受体激活配体，如生长因子、细胞因子和（共）免疫刺激配体，将其融合到抗体或抗体片段中，以诱导局部或组织特异性激动活性，从而诱导细胞反应。越来越多的这种抗体-配体融合蛋白正在进入临床试验。受体激活也可以使用激动性抗体来实现。针对靶抗原和肿瘤坏死因子超家族（TNFRSF）成员的bsAbs已被证明是具有强大活性和肿瘤选择性的激动分子。RG7386（RO6874813）是一种四价bsAb，靶向癌症相关成纤维细胞上的FAPα和DR5，在具有FAPα间质表达的小鼠模型中具有效和选择性的肿瘤细胞杀伤，并已进入临床测试。此外，BI905711，一种靶向DR5和CDH17的四价双特异性IgG-scFv融合蛋白，目前处于I期临床研究中。靶向递送有效载荷的bsAb存在两种概念上不同的方法来利用bsAbs靶向递送有效载荷，如细胞毒性药物或放射性药物。第一种方法，预靶向治疗，使用bsAb的一个臂特异性靶向肿瘤细胞，另一个臂随后捕获有效载荷到肿瘤细胞。GD2 x DOTA是一种识别GD2的bsAb，并捕获放射性有效载荷177Lu-DOTA，其在TME中组装。在没有四聚化的情况下，由于半衰期，它会被迅速从外围清除。然而，到目前为止，临床试验中很少有bsAbs利用这种MoA，这可能是因为放射性预靶向涉及复杂的导流，限制了其普遍适用性。第二种方法通过递送偶联到双特异性抗体上的细胞毒性有效载荷，实现肿瘤细胞的特异性靶向。目前，bsADC已成为肿瘤药物开发的热点，已有多款bsADC进入临床开发，如ZW49、REGN5093、BL-B01D1等。靶向癌症免疫治疗的bsAb癌症免疫疗法中使用的大多数bsAbs通过T细胞驱动的天然或内源性免疫发挥作用，包括免疫检查点抑制（CPIs）效应细胞接合器（包括TCE和ICEs）以及共刺激性bsAb。双免疫检查点抑制许多抑制免疫检查点的单特异性抗体，如CTLA4或PD-1/PDL-1，已被批准用于癌症免疫疗法。将检查点抑制性抗体疗法扩展到bsAbs可以减少不期望的副作用，并增强疗效。大多数双免疫检查点抑制剂靶向PD-1/PD-L1轴和其他免疫抑制分子，如CTLA-4、TIM-3、LAG-3或TIGIT。MEDI5752（PD-1×CTLA-4）抑制PD-1+激活的T细胞中CTLA-4的功能，诱导PD-1的快速内化和降解。与PD-1和CTLA-4单抗联合治疗相比，MEDI5752的活性显著增强。针对其他检查点分子的双功能性抑制剂，包括LAG-3和TIGIT，也正在开发中。效应细胞接合器细胞接合器连接两种不同类型的细胞，主要是肿瘤细胞和T/NK细胞，以诱导肿瘤细胞溶解。细胞接合器由TAA靶向部分和效应细胞识别部分组成，并进一步分为T细胞接受器和NK细胞接受器。T细胞接合器利用TAA和TCR成分（主要是CD3），它们连接肿瘤细胞和T细胞，绕过TCR-MHC-I相互作用。因此，无论抗原特异性如何，T细胞结合器都会触发T细胞活化，产生包括穿孔素和颗粒酶在内的细胞毒性分子，以杀伤肿瘤细胞。BiTE是T细胞结合器的一种形式，通过靶向TAA和CD3的单链抗体将肿瘤细胞和T细胞结合，用于T细胞介导的肿瘤细胞杀伤。靶向CD19和CD3的blinatumomab是临床上典型的BiTE，2014年，blinatumomab成为第一个被FDA批准的BsAb，用于治疗ALL患者，在随后的几年里，blinatumomab的治疗范围进一步拓宽，2018年，FDA批准其用于首次或第二次完全缓解后MRD≥0.1%的pre-B ALL患者群体的治疗。目前，超过60例BiTE形式的双抗正在进行I/II期临床试验。NK细胞接合器将CD16A+NK细胞重定向至肿瘤细胞，诱导NK细胞活化。与BiTE相比，NK细胞接受者表现出较少的不良反应，如细胞因子释放综合征（CRS）和神经毒性。多种细胞毒性受体可激活NK细胞：CD16（FcγRIII）、天然细胞毒性受体（NCR；NKp30、NKp44、NKp46）、C型凝集素样受体NKG2D（CD314）和CD94/NKG2C。最近，抗CD30×CD16A的NK细胞接合器（AFM13）在AACR 2022的报告中展示了不俗的抗肿瘤效果。共刺激bsAbs高效、持久和局部受限的抗肿瘤免疫反应需要共刺激和共抑制信号来严格调节细胞毒性T细胞、自然杀伤细胞和巨噬细胞的激活、分化和维持。TNFRSF家族的成员（如4-1BB、CD40、OX40、GITR、CD27或CD30）以及CD28免疫球蛋白超家族（如CD28、CTLA4、PD-1、ICOS、BTLA)及其相应的配体在介导免疫调节信号中发挥着重要作用。靶向这些免疫调节途径可以增强免疫治疗。PRS-343（cinrebafusp），是一种针对HER2和4-1BB的四价bsAb，在IND研究中其耐受性良好，没有明显和相关的药物相关毒性；在接受有效剂量治疗的患者中（n=33），12%的患者达到ORR，包括1个CR，疾病控制率（DCR）为52%。bsAbs中通过4-1BB进行肿瘤选择性共刺激的其他靶点还包括EGFR、PSMA、CLDN18.2、B7H4、CEACAM5、HER2、PD-L1和FAP。此外，十多种针对PD-L1和4-1BB的不同bsAbs处于I期或II期试验中。bsAb的新概念bsAbs的领域仍在进一步探索和扩展技术和应用，可能提供目前正在开发的bsAb尚未解决的治疗概念。三特异性TCE共刺激信号可以与双特异性TCE组合以促进更加有效的T细胞活化。这样的三特异性TCE目前正在针对TAA和CD3的临床试验中，并且进一步包含抗CD28结合位点。SAR443216是一种针对HER2×CD3×CD28的三特异性抗体，能够强力激活CD4+和CD8+T细胞，诱导T细胞增殖、细胞因子和颗粒酶B的释放，以及T细胞介导的对表达HER2的肿瘤细胞的杀伤，其目前处于I期临床研究中。在类似的方法中，SAR442257是另一种CD38×CD3×CD28的三特异性抗体。前药方法一种新兴的方法是在肿瘤处选择性激活的前药，产生具有高度肿瘤特异性功能的bsAbs。前药转化为功能性bsAbs可以通过环境触发因素如肿瘤相关蛋白酶来实现。双重肿瘤靶向的另一种前药方法依赖于来自两个具有分裂CD3ε结合部分的肿瘤特异性组装。这些分子需要被设计为非活性的独立实体并在循环中，使得它们仅在肿瘤抗原结合和随后的原位组装时被激活。PROTAC bsAbs另一个新兴概念和新的MoA利用bsAbs通过靶向降解来抑制增殖相关过程。类似于双特异性或多特异性小分子蛋白水解靶向嵌合体（PROTACs），bsAbs可被设计为触发参与癌症发展或进展的表面蛋白的内化和随后的降解。这样的bsAbs同时与靶向降解的蛋白质和降解的因子结合，并触发内化，如膜上的E3泛素连接酶或转铁蛋白受体。目前，抗体-PROTAC概念仍处于早期开发阶段，迄今为止还没有进入临床研究。bsAb递送bsAb开发中另一个重要的新兴概念是bsAb的局部产生和随后的局部递送，如通过脂质纳米颗粒介导的mRNA递送的CLDN6 TCE、溶瘤病毒或包括CAR-T细胞在内的基因治疗方法。细胞因子模拟抗体最后，bsAbs也可以作为细胞因子模拟物或所谓的合成细胞因子激动剂。scFvs或基于单域抗体VHH的方法可以通过模拟IL-2或IL-15、IL-18、I型干扰素和IL-10来有效地触发细胞因子信号传导。这种基于抗体的细胞因子模拟物可能在癌症免疫疗法中具有各种应用。小结bsAbs领域最近取得了实质性进展，到2023年底，已有十几种bsAbs获得批准，许多不同的方法正在临床上进行测试。尽管如此，由于癌症的异质性和适应性，这些方法中的任何一种都不太可能成为普遍的癌症免疫疗法。相反，抗体需要针对某些应用量身定制，并将依赖于与其他方法的结合，以最大限度地提高其疗效和安全性。在不久的将来，多特异性抗体疗法的发展可能会在以下四个领域出现增长：针对具有明确依赖性的肿瘤相关RTK的bsAbs；用于以增加的选择性靶向肿瘤的bsADC；用于靶向降解适用于各种途径的细胞表面蛋白的双特异性PROTAC；以及用于癌症免疫疗法的多特异性抗体。与其他治疗癌症的药物一样，通过改进的诊断方法和新的开发模式，将bsAbs和多特异性抗体疗法应用于早期患者，对于实现治愈癌症患者的目标至关重要。参考文献：1. The present and future of bispecific antibodies for cancer therapy. Nat Rev Drug Discov.2024 Mar 6.2. Development of Bispecific Antibody for CancerImmunotherapy: Focus on T Cell Engaging Antibody. Immune Netw. 2022 Feb; 22(1): e4.文章信息源于公众号小药说药，登载该文章目的为更广泛的传递行业信息，不代表赞同其观点或对其真实性负责。文章版权归原作者及原出处所有，文章内容仅供参考。本网拥有对此声明的最终解释权，若无意侵犯版权，请联系小编删除。学如逆水行舟，不进则退；心似平原走马，易放难收。行舟Drug每日更新 欢迎订阅+医药大数据|行业动态|政策解读