HIV Subtype C Alphavirus Vaccine Design & Development

申请方的目的是基于来自南非的HIV亚型C临床分离株开发甲病毒复制子颗粒（VRP）疫苗。申请人已经开发了一种初始产品设计，其中包含通过HVTN进行的初始I期试验的gag基因，并已开始对第二个I期试验的替代多基因疫苗进行临床前评价。此外，不同的VRP糖蛋白外壳在免疫原性、剂量和生产方面提供了可能的优势。申请人的提案涉及三个目标： 目的1：与C亚型HIV gag VRP疫苗的GMP生产相关的工作。本目标旨在完成开发工作和GMP生产，以回应FDA根据2001年12月提交的IND提出的临床暂停问题：a）建立新的Vero细胞库并进行细胞库外源因子和致瘤性检测，B）生产中试和GMP批次并进行放行检测（外源因子检测），c）进行中试和GMP批次的稳定性和免疫原性检测，d）准备并提交IND修正案。 目标二：该目标建立在申请人迄今为止在设计和构建多个替代性多基因VRP构建体方面的努力的基础上，所述多基因VRP构建体采用gag、pol、env和 各种单一和组合复制子中的nef基因，以及将生产工艺推进到I期试验之后所需的工艺改进：a）评估并将替代工艺改进纳入生产工艺：1）减少或消除培养基中的血清，2）评价替代制剂以提高稳定性，3）评价肝素亲和层析的替代方案以提高纯度，4）评价提高VRP产率和规模的工艺改进，5）确认新的分析检测方法并启动含量测定验证工作; B）生产2-3个中试批次并转移新的生产 向GMP分包商提供工艺和检测方法;生产、检测和放行2-3个GMP批次;实施稳定性计划;进行临床前GLP毒理学和免疫原性检测;与HVTN一起制定临床方案并准备IND。 目标3：与替代糖蛋白包衣研究相关的努力。生产实验室规模的多基因VRP与现有的和新的糖蛋白外壳，比较小鼠免疫原性导致灵长类动物研究在国防部合作。

The applicant's objective is to develop an alphavirus replicon particle (VRP) vaccine based on HIV subtype C clinical isolates from South Africa. The applicant has developed an initial product design incorporating the gag gene for an initial phase I trial via the HVTN, and has initiated preclinical evaluation of alternative multi-gene vaccines for a second phase 1 trial. In addition, different VRP glycoprotein coats offer possible advantages in immunogenicity, dose, and production. The applicant's proposal addresses three objectives: Objective 1: efforts related to GMP production of subtype C HIV gag VRP vaccine. This objective aims to complete development work and GMP manufacture in response to clinical hold questions received from the FDA under an IND submitted in December, 2001: a) establish new Vero cell banks and conduct cell bank adventitious agent and tumorigenicity testing, b) manufacture pilot and GMP lots and conduct release testing (adventitious agent tests) of GMP lot, c) conduct stability and immunogenicity testing of pilot and GMP lots, d) prepare and submit IND amendment. Objective 2: efforts related to GMP production and IND submission of a multi-gene subtype C HIV VRP vaccine, This objective builds on the applicant's efforts to date in the design and construction of multiple alternative multi-gene VRP constructs employing the gag, pol, env, and nef genes in various single and combined replicons, and in process improvements needed to advance the manufacturing process beyond phase I trials: a) evaluate and incorporate alternative process improvements to the manufacturing process: 1) decrease or eliminate serum from the culture media, 2) evaluate alternative formulations to improve stability, 3) evaluate alternatives to heparin affinity chromatography to increase purity, 4) evaluate process modifications that increase VRP yield and scaleability, 5) qualify new analytical test methods and initiate assay validation work; b) produce 2-3 pilot lots and transfer new manufacturing process and test methods to GMP subcontractor; manufacture, test, and release 2-3 GMP lots; implement stability program; conduct preclinical GLP toxicology and immunogenicity testing; develop clinical protocol with HVTN and prepare IND. Objective 3: efforts related to study of alternative glycoprotein coats. Produce lab-scale multi-gene VRP with existing and new glycoprotein coats, compare mouse immunogenicity leading to primate studies in a DoD collaboration.