COVID (Dec 2022)

Repeat-Dose Toxicity of Candidate Omicron COVID-19 Vaccine in Sprague-Dawley Rats

  • Yuxiu Zhao,
  • Zhenyu He,
  • Zhanhui Wang,
  • Yao He,
  • Xue Zhao,
  • Hongyang Liang,
  • Yancen Guo,
  • Yichuan Wang,
  • Xiaonan Zhang,
  • Huiqin Zhu,
  • Yuan Dong,
  • Yingwei Liu,
  • Wanli Li,
  • Ling Ding,
  • Xiujuan Zhu,
  • Haoyue Lan,
  • Yuntao Zhang,
  • Hui Wang,
  • Xiaoming Yang

DOI
https://doi.org/10.3390/covid3010003
Journal volume & issue
Vol. 3, no. 1
pp. 51 – 64

Abstract

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Due to a large number of mutations in the spike protein and immune escape, the Omicron variant (B.1.1.529) has become a predominant variant of concern (VOC) strain. To prevent the disease, we developed a candidate inactivated vaccine (Omicron COVID-19 Vaccine (Vero Cell), Inactivated). To evaluate the safety of the vaccine, we tested the repeat-dose toxicity in Sprague-Dawley (SD) rats. The doses were administered randomly to three groups: physiological saline solution (control), aluminum adjuvant in PBS solution adjuvant (adjuvant group), and low-dose and high-dose omicron vaccines (vaccine group) for 6 weeks. The SD rats were allowed to recover for 4 weeks after withdrawal. We evaluated the physiological condition of the rats, including their ophthalmological condition, body weight, food intake, body temperature, blood biochemistry, urine, neutralizing antibody, inflammation at the injection site, and organs weight. In summary, no dose-dependent adverse toxicological changes were observed, and a recovery trend was obvious, which proved the preclinical safety of the candidate omicron vaccine and provided evidence for clinical trials in humans.

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