A Pan-Dengue Virus Immunotherapeutic for Prevention and Treatment

描述(由申请人提供)：该项目的最终目标是开发一种获得许可的免疫疗法，以预防和治疗由登革病毒(DV)感染引起的各种发热性疾病。这里提出的工作将导致验证具有体内有效性的候选产品，开发制造工艺并完成所有使能IND的研究，极大地推动该候选产品走向临床。二次感染DV的个体通常会经历更严重的疾病，原因是初次感染的抗体中和能力差，通过Fc受体将DV颗粒招募到单核细胞，从而导致感染的抗体依赖增强(ADE)。我们提出的免疫疗法将被设计成消除Fc？R结合，从而消除ADE，同时保持较长的血清半衰期和结合补体的能力，从而增强治疗活性。这项工作将通过4个具体目标进行。(1)设计一种有效的、半衰期长的免疫治疗鸡尾酒，中和所有四种DV血清型，最大限度地减少对逃逸突变的选择，同时防止感染的抗体依赖增强(ADE)。现有的有效的血清型特异性单抗将被用作构建多价、多特异性抗体样分子(IgDART)的基础，这些分子具有许多抗体的理想治疗特性，并且易于表达和纯化。对于具有多个靶点的疾病，与使用单抗相比，IgDART可以产生成分更少的更简单的鸡尾酒。在DV的情况下，4个血清型将被两个IgDART分子中和。还将设计一种交叉反应的单抗，作为药物鸡尾酒的重要最终成分，以控制逃逸突变的出现。活动将包括人性化、亲和力成熟以提高效力、去免疫和产生IgDART。(2)在小鼠身上进行体内研究，以建立预防、治疗和药代动力学活性的参数，以及测量控制逃逸突变出现的能力。(3)产品开发和制造。将为每个分子(2个IgDART和1个单抗)建立优化的表达、纯化和配方条件。将建立细胞库，以产生适合人类使用的材料，这些材料将在cGMP条件下生产。(4)完成支持IND的研究。疗效、毒理学和药代动力学将在非人类灵长类动物模型中进行评估。将进行人类和非人类灵长类组织的交叉反应研究。所要求的研究将在GLP条件下进行。该项目旨在将一系列DV中和单抗发展为一种简洁、定义明确的免疫疗法，可用于启动临床研究。

DESCRIPTION (provided by applicant): The ultimate goal of this project is to develop a licensed immunotherapeutic to prevent and treat the spectrum of febrile illnesses caused by Dengue virus (DV) infection. The work proposed here will result in the validation of product candidates with proven efficacy in vivo, development of manufacturing process and completion of all IND-enabling studies, significantly advancing this product candidate toward clinical use. Individuals infected a second time by DV generally experience more severe disease resulting from poorly neutralizing antibodies from the primary infection leading to an antibody-dependent enhancement (ADE) of infection by recruiting DV particles to monocytes, their primary cellular targets of infection, via Fc??receptors. The immunotherapeutic that we propose will be engineered to eliminate Fc?R binding, and therefore ADE, while maintaining long serum half-life and the ability to bind complement that enhances therapeutic activity. The work will progress through 4 Specific Aims. (1) Engineer a potent, long half-life immunotherapeutic cocktail that neutralizes all four DV serotypes and minimizes selection for escape mutants, while preventing antibody dependent enhancement (ADE) of infection. Existing potent serotype specific MAbs will be used as the basis to build multivalent, multispecific antibody like molecules (IgDARTs) that have many of the desirable therapeutic properties of antibodies and are easily expressed and purified. For diseases with multiple targets, IgDARTs allow generation of simpler cocktails with fewer components than if MAbs were employed. In the case of DV, 4 serotypes will be neutralized by two IgDART molecules. A cross- reactive MAb will also be engineered to serve as an important final component of the drug cocktail to control emergence of escape mutants. Activities will include humanization, affinity maturation to increase potency, de-immunization, and generation of IgDARTs. (2) Perform in vivo studies in mice to establish parameters of prophylactic, therapeutic, and pharmacokinetic activity, as well as measuring the ability to control emergence of escape mutants. (3) Product development and manufacturing. Optimized expression, purification, and formulation conditions will be established for each molecule (2 IgDARTs and 1 MAb). Cell banks will be established for the generation of material suitable for human use that will be manufactured under cGMP conditions. (4) Complete IND-enabling studies. Efficacy, toxicology, and pharmacokinetics will be evaluated in non-human primate models. Human and non-human primate tissue cross-reactivity studies will be performed. Required studies will be performed under GLP conditions. This project aims to advance a collection of DV-neutralizing MAbs into a concise well-defined immunotherapeutic validated for initiation of clinical studies.