Monoclonal Antibody Cocktail for Treatment of Marburg Virus Disease

项目摘要 埃博拉(EBOV)和马尔堡(Marv)病毒导致人类和非人类的出血热疾病 灵长类动物的病死率高达90%。2013-2016年埃博拉病毒病(EVD)爆发 导致超过2.8万例病例和1.1万人死亡，并对西非国家的经济造成巨大损失， 在没有任何疫苗或治疗选择的情况下。这场疫情的爆发引发了前所未有的全球努力 埃博拉病毒病疫苗和治疗药物的发展，并导致了一种批准的疫苗和两种单抗 (MAB)治疗学。重要的是，对EBOV单抗和后来的SARS-CoV2单抗的研究证实了 有效治疗病毒性疾病的MAB鸡尾酒。与EVD相比，治疗方法的发展 尽管马尔堡病毒病(MVD)爆发了几次，包括2022年的一次，但MVD一直滞后。这个 针对MPI阶段I/II Fast Track SBIR应用的研究人员已经开发出两类靶向mAbs Marv受体结合位点(RBS)和内部融合环(IFL)内的非重叠表位 糖蛋白(GP)。RBS结合单抗(MR186)主要通过效应器功能提供保护，而 IFL结合剂(R217)是迄今为止发现的最有效的中和MARV单抗。MR186已经成为 利用Fc部分的YTE突变来提高生物利用度，并在岩藻糖基- 转移酶缺陷CHO细胞株增强效应器功能(MR186-YTEAF)。我们目前正在推出 YTE突变为R217 Fc产生治疗候选R217-YTE。在这个提议的项目中，我们 利用这些互补的作用机制来开发这两种单抗的高效鸡尾酒 MVD治疗。MAb鸡尾酒的使用也有望降低逃逸变种的风险。该提案有四个方面 明确的目标。在目标1(第一阶段部分)中，将在ExpiCHO细胞中产生R217-YTE，并对其进行充分鉴定。 鸡尾酒的卓越疗效将在Marv-安哥拉的豚鼠模型中得到展示，这一里程碑 将用于过渡到第二阶段SBIR。第二阶段从目标2开始，在目标2中鸡尾酒的功效 将在NHP模型中测试一系列自适应设计的NHP实验，最终获得卓越的疗效 将与单项单抗进行正式演示比较。在目标3中，我们将评估 几种NHP药效血清中抗体的药代动力学(PK)和药效学(PD) 研究包括在目标1中进行的研究。PK/PD数据与临床结果之间的相关性将是 探索过了。目标4我们将专注于在CHO细胞中建立稳定的制造细胞系，并至少 每个单抗的四个克隆将被生产出来，用于未来的GMP细胞库。如果成功，我们预计 在国防部或BARDA资助下进一步开发该产品，并根据FDA动物规则获得批准。

Project Summary Ebola (EBOV) and Marburg (MARV) viruses cause hemorrhagic fever disease in humans and nonhuman primates (NHPs) with case-fatality rates as high as 90%. The 2013-2016 Ebola Virus Disease (EVD) outbreak led to over 28,000 cases and 11,000 deaths and took an enormous toll on the economy of West African nations, in the absence of any vaccine or therapeutic options. This outbreak spurred an unprecedented global effort for development of vaccines and therapeutics for EVD and led to an approved vaccine and two monoclonal antibody (mAb) therapeutics. Importantly studies with EBOV mAbs and later SARS-CoV2 mAbs established the value of mAb cocktails for effective treatment of viral diseases. In contrast to EVD, development of therapeutics for Marburg Virus Disease (MVD) has been lagging despite several MVD outbreaks including one in 2022. The investigators on this MPI Phase I/II Fast Track SBIR application have developed two classes of mAbs targeting non-overlapping epitopes within the receptor binding site (RBS) and the internal fusion loop (IFL) of MARV glycoprotein (GP). The RBS-binding mAb (MR186), provides protection primarily through effector functions, while the IFL-binder (R217) is the most potent neutralizing MARV mAb discovered to-date. MR186 has been engineered to enhance bioavailability using YTE mutation in the Fc portion, and produced in a fucosyl- transferase deficient CHO cell line to enhance effector functions (MR186-YTEAF). We are currently introducing YTE mutations into R217 Fc to generate the therapeutic candidate R217-YTE. In this proposed project we harness these complementary mechanisms of action to develop a highly effective cocktail of these two mAbs for MVD treatment. Use of mAb cocktail is also expected to reduce the risk of escape variant. The proposal has four Specific Aims. In Aim 1 (Phase I portion), R217-YTE will be produced in ExpiCHO cells and fully characterized. Superior efficacy of the cocktail will be demonstrated in a guinea pig model of MARV-Angola and this milestone will serve for transition to Phase II SBIR. Phase II Portion starts with Aim 2, in which the efficacy of the cocktail will be tested in NHP models in series of adaptively designed NHP experiments and finally the superior efficacy will be formally demonstrated in comparison with the individual mAbs. In Aim 3 we will evaluate the pharmacokinetics (PK) and pharmacodynamics (PD) of the antibodies in sera from a number of NHP efficacy studies including studies performed in Aim 1. Correlations between PK/PD data and clinical outcome will be explored. Aim 4 we will be focused on generation of stable manufacturing cell lines in CHO cells and at lease four clones of each mAb will be produced to be used for future GMP cell banks. If successful, we anticipate further development of the product under DoD or BARDA funding and approval under FDA Animal Rule.