An adenovirus-vectored COVID-19 vaccine confers protection from SARS-COV-2 challenge in rhesus macaques
Liqiang Feng, Qian Wang, Chao Shan, Chenchen Yang, Ying Feng, Jia Wu, Xiaolin Liu, Yiwu Zhou, Ren-Di Jiang, Peiyu Hu, Xinglong Liu, Fan Zhang, Pingchao Li, Xuefeng Niu, Yichu Liu, Xuehua Zheng, Jia Luo, Jing Sun, Yingying Gu, Bo Liu, Yongcun Xu, Chufang Li, Weiqi Pan, Jincun Zhao, Changwen Ke, Xinwen Chen, Tao Xu, Nanshan Zhong, Suhua Guan, Zhiming Yuan, Ling Chen
Abstract
Abstract The rapid spread of coronavirus SARS-CoV-2 greatly threatens global public health but no prophylactic vaccine is available. Here, we report the generation of a replication-incompetent recombinant serotype 5 adenovirus, Ad5-S-nb2, carrying a codon-optimized gene encoding Spike protein (S). In mice and rhesus macaques, intramuscular injection with Ad5-S-nb2 elicits systemic S-specific antibody and cell-mediated immune (CMI) responses. Intranasal inoculation elicits both systemic and pulmonary antibody responses but weaker CMI response. At 30 days after a single vaccination with Ad5-S-nb2 either intramuscularly or intranasally, macaques are protected against SARS-CoV-2 challenge. A subsequent challenge reveals that macaques vaccinated with a 10-fold lower vaccine dosage (1 × 10 10 viral particles) are also protected, demonstrating the effectiveness of Ad5-S-nb2 and the possibility of offering more vaccine dosages within a shorter timeframe. Thus, Ad5-S-nb2 is a promising candidate vaccine and warrants further clinical evaluation.