Rapid generation and testing of live-attenuated vaccines against SARS-CoV-2

显然，对预防由SARS-CoV-2引起的2019年冠状病毒病(COVID19)持续流行的疫苗的需求尚未得到满足。SARS-CoV-2于2019年底在湖北省中国首次发现。 SARS-CoV-2具有高度传染性(R0为1.4-3.9，高于季节性流感)，并表现为发烧， 咳嗽、疲劳和呼吸急促。年长的患者和有潜在健康状况的患者可能在 严重疾病的风险更高，报告的大多数病例发生在成年人(中位数59岁)。 目前还没有针对SARS-CoV-2的疫苗或其他医学对策。本意见书是一个 1R44AI131756-01的行政补充，以回应NOT-AI-20-030，其中我们描述了我们的 我们的SARS-CoV-2候选疫苗临床前测试的方法。在家长拨款申请中， Codagenix正在开发一种安全有效的RSV疫苗，该疫苗基于Codagenix基于算法的平台 疫苗的快速生成。由RSV和SARS-CoV-2引起的呼吸道疾病加在一起，是主要的 公共卫生威胁。在这份行政副刊中，我们试图应用我们的“合成减毒病毒” 工程“(SAVE)平台，设计和开发SARS-CoV-2减毒活疫苗(LAV)。 SAVE依赖于大规模的DNA合成和对目标病毒的合理重新设计来构建一种 人类细胞中蛋白质表达的“去最佳化”。SAVE平台已被用于生产疫苗 对抗多种病毒，包括流感、寨卡病毒、登革热、呼吸道合胞病毒等。一种基于节省的疫苗是 目前正在进行一项美国IND的第一阶段临床试验，另一项正在进入第一季度至2020年的临床试验， 论证了拯救背后的原则证明。我们已经启动了SARS-CoV-2疫苗的开发 实时应对持续的SARS-CoV-2疫情。使用我们的SAVE平台，我们设计了六个 在RdRp和Spike基因上不同程度地去优化的候选疫苗，以及 合成wt SARS-CoV-2。这些基因组被从头合成、组装、测序，现在 在细胞培养中转染后准备恢复。候选疫苗病毒将在以下情况下恢复 BSL-3包涵体，传代，深度测序，并筛选减毒、免疫原性和有效性 灵长类模型。我们预计至少有一种病毒，但很可能有4种病毒将从转基因中恢复。其中三个 生长最好的病毒(生长到104TCID50/ml)将在以下方面进行安全性、免疫原性和有效性测试 非洲绿猴子，以前用于SARS研究。在完成所述工作之后 在这里，使用非赠款资金，在灵长类研究中表现最好的两种病毒将通过GLP 毒性筛选、GMP制造和I期临床试验。

There is a clear unmet need for a vaccine against the ongoing epidemic of coronavirus disease 2019 (COVID19) caused by SARS-CoV-2. SARS-CoV-2 was initially detected in the Hubei Province of China late in 2019. SARS-CoV-2 is highly contagious (R0 of 1.4-3.9, greater than seasonal influenza), and presents with fever, cough, fatigue, and shortness of breath. Older patients and those with underlying health conditions may be at a higher risk of severe illness, with most reported cases having occurred in adults (median 59 years of age). There are no vaccines or other medical countermeasures available against SARS-CoV-2. This submission is an Administrative Supplement to 1R44AI131756-01 in response to NOT-AI-20-030, where we describe our approach to pre-clinical testing of our SARS-CoV-2 vaccine candidates. In the parent grant application, Codagenix is developing a safe and effective RSV vaccine based on Codagenix’s algorithm-based platform for rapid generation of vaccines. Together, the respiratory illnesses caused by RSV and SARS-CoV-2 present major public health threats. In this administrative supplement, we seek to apply our “synthetic attenuated virus engineering" (SAVE) platform to design and develop a live-attenuated vaccine (LAV) against SARS-CoV-2. SAVE relies on large-scale DNA synthesis and rational re-design of a target virus to construct a vaccine that is “deoptimized” for protein expression in human cells. The SAVE platform has been used to generate vaccines against multiple viruses including influenza, Zika, dengue, RSV, and others. One SAVE-based vaccine is currently in the clinic in Phase I trials under a US IND, and another entering clinical trials in Q1-20, demonstrating the proof of principle behind SAVE. We already initiated the SARS-CoV-2 vaccine development in a real-time response to the ongoing epidemic of SARS-CoV-2. Using our SAVE platform, we designed six vaccine candidates that are deoptimized to varying extents across the RdRp and Spike genes, along with a synthetic wt SARS-CoV-2. These genomes were synthesized de novo, assembled, sequenced, and are now ready for recovery following transfection in cell culture. Candidate vaccine viruses will be recovered under BSL-3 containment, passaged, deep sequenced, and screened for attenuation, immunogenicity and efficacy in a primate model. We expect at least one, but likely 4 viruses will be recovered from transfection. Three of the best-growing viruses (growing to >104 TCID50/ml) will be tested for safety, immunogenicity and efficacy in African green monkeys, previously used for SARS studies. Following the completion of the work described here, using non-grant funding, two of the viruses that perform best in primate studies will be put through GLP toxicity screening, GMP manufacturing and a Phase I clinical trials.