In March 2020, the first cases of the human coronavirus disease COVID-19 were registered in Kazakhstan. We isolated the SARS-CoV-2 virus from clinical materials from some of these patients. Subsequently, a whole virion inactivated candidate vaccine, QazCovid-in, was developed based on this virus. To develop the vaccine, a virus grown in Vero cell culture was used, which was inactivated with formaldehyde, purified, concentrated, sterilized by filtration, and then adsorbed on aluminum hydroxide gel particles. The formula virus and adjuvant in buffer saline solution were used as the vaccine. The safety and protective effectiveness of the developed vaccine were studied in Syrian hamsters. The results of the studies showed the absolute safety of the candidate vaccine in the Syrian hamsters. When studying the protective effectiveness, the developed vaccine with an immunizing dose of 5 μg/dose specific antigen protected animals from a wild homologous virus at a dose of 10⁴.⁵ TCID_50/mL. The candidate vaccine induced the formation of virus-neutralizing antibodies in vaccinated hamsters at titers of 3.3 ± 1.45 log2 to 7.25 ± 0.78 log2, and these antibodies were retained for 6 months (observation period) for the indicated titers. No viral replication was detected in vaccinated hamsters, protected against the development of acute pneumonia, and ensured 100% survival of the animals. Further, no replicative virus was isolated from the lungs of vaccinated animals. However, a virulent virus was isolated from the lungs of unvaccinated animals at relatively high titers, reaching 4.5 ± 0.7 log TCID₅₀/mL. After challenge infection, 100% of unvaccinated hamsters showed clinical symptoms (stress state, passivity, tousled coat, decreased body temperature, and body weight, and the development of acute pneumonia), with 25 ± 5% dying. These findings pave the way for testing the candidate vaccine in clinical human trials.

2020 年 3 月，哈萨克斯坦登记了首例人类冠状病毒病 COVID-19。我们从其中一些患者的临床材料中分离出 SARS-CoV-2 病毒。随后，基于该病毒开发了一种全病毒体灭活候选疫苗 QazCovid-in。为了开发疫苗，使用在 Vero 细胞培养物中生长的病毒，用甲醛灭活、纯化、浓缩、过滤灭菌，然后吸附在氢氧化铝凝胶颗粒上。以缓冲盐水溶液中的配方病毒和佐剂作为疫苗。在叙利亚仓鼠中研究了开发的疫苗的安全性和保护有效性。研究结果表明，候选疫苗在叙利亚仓鼠中是绝对安全的。在研究保护效果时，⁴ . ⁵ TCID _{50 /}毫升。候选疫苗以 3.3 ± 1.45 log2 至 7.25 ± 0.78 log2 的滴度在接种的仓鼠中诱导病毒中和抗体的形成，并且这些抗体保留 6 个月（观察期）达到指定的滴度。在接种疫苗的仓鼠中未检测到病毒复制，从而防止了急性肺炎的发展，并确保了动物 100% 的存活率。此外，没有从接种动物的肺中分离出复制病毒。然而，从未接种疫苗的动物的肺中分离出一种毒力病毒，滴度相对较高，达到 4.5 ± 0.7 log TCID ₅₀/毫升。攻击感染后，100% 未接种疫苗的仓鼠表现出临床症状（应激状态、被动、被毛凌乱、体温和体重下降以及发生急性肺炎），其中 25 ± 5% 死亡。这些发现为在临床人体试验中测试候选疫苗铺平了道路。