外泌体是细胞外囊泡的一种，其直径在30-150 nm，在体内可以由多种类型的细胞分泌，并可以通过体液等方式的运输，到达靶细胞区域，进而被靶细胞摄取，从而影响靶细胞的生存、信号传递、增殖和凋亡等多种生理活动。

 

由于外泌体本身的很多特点，目前已经尝试被运用到疾病的诊断和治疗中。首先，外泌体异质性强并可以反映母体细胞的特性，赋予了其在疾病诊断中的重要用途。其次，由于外泌体在体内广泛存在，且承担物质运输和信号交流的重要功能，因此可作为一种治疗药物或者药物递送载体来使用，并具有免疫原性低、毒性小、可通过血脑屏障等优势，在多个研究团队和企业中进行了概念验证和临床开发。

 

在外泌体作为药物递送载体进行疾病治疗的工艺流程中，涉及母体细胞的选择与培养，外泌体的提取，外泌体的药物装载，外泌体的靶向性改造，外泌体的储存和外泌体的给药与治疗等多个核心过程，并且目前国际上尚无外泌体生产和改造的标准，因此，企业的外泌体的生产和改造工艺也是判断企业的核心竞争力的重要因素。

 

目前，参与外泌体药物递送载体研发的龙头企业主要有Codiak Biosciences、Evox Therapeutics、Aruna Bio等，他们分别聚焦于肿瘤领域、代谢疾病领域和中枢神经系统疾病领域。Codiak Biosciences已有两款产品（exoIL-12和exoSTING）进入临床Ⅰ期的开发阶段，从已公布的exoIL-12TM的临床Ⅰ期部分数据来看其安全性表现良好。另外，仅在2020年，有多家外泌体药物递送载体在研企业与大药企（如礼来、武田）进行合作，该领域深受大药企青睐。

 

 

 

 

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13. 公司官网：Codiak Biosciences；Evox Therapeutics；Aurna Bio.