Immunogenicity of Tetravalent Protein Vaccine SCTV01E-2 against SARS-CoV-2 EG.5 Subvaraint: A Phase 2 Trial
Jihai Tang,
Qinghua Xu,
Chaoyin Zhu,
Kun Xuan,
Tao Li,
Qingru Li,
Xingya Pang,
Zhenqiu Zha,
Jinwei Li,
Liyang Qiao,
Haiyang Xu,
Gang Wu,
Yan Tian,
Jun Han,
Cuige Gao,
Jiang Yi,
Gui Qian,
Xuxin Tian,
Liangzhi Xie
Affiliations
Jihai Tang
Anhui Provincial Center for Disease Control and Prevention, Public Health Research Institute of Anhui Province, Hefei 230601, China
Qinghua Xu
Anhui Provincial Center for Disease Control and Prevention, Public Health Research Institute of Anhui Province, Hefei 230601, China
Chaoyin Zhu
Funan County Center for Disease Control and Prevention, Fuyang 236399, China
Kun Xuan
Anhui Provincial Center for Disease Control and Prevention, Public Health Research Institute of Anhui Province, Hefei 230601, China
Tao Li
Anhui Provincial Center for Disease Control and Prevention, Public Health Research Institute of Anhui Province, Hefei 230601, China
Qingru Li
Anhui Provincial Center for Disease Control and Prevention, Public Health Research Institute of Anhui Province, Hefei 230601, China
Xingya Pang
Anhui Provincial Center for Disease Control and Prevention, Public Health Research Institute of Anhui Province, Hefei 230601, China
Zhenqiu Zha
Anhui Provincial Center for Disease Control and Prevention, Public Health Research Institute of Anhui Province, Hefei 230601, China
Jinwei Li
Fuyang Center for Disease Control and Prevention, Fuyang 236030, China
Liyang Qiao
Funan County Center for Disease Control and Prevention, Fuyang 236399, China
Haiyang Xu
Fuyang Center for Disease Control and Prevention, Fuyang 236030, China
Gang Wu
Funan County Center for Disease Control and Prevention, Fuyang 236399, China
Yan Tian
Funan County Center for Disease Control and Prevention, Fuyang 236399, China
Jun Han
State Key Laboratory of Infectious, Disease Prevention and Control, National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 102206, China
Cuige Gao
Beijing Engineering Research Center of Protein and Antibody, Sinocelltech Ltd., Beijing 100176, China
Jiang Yi
Beijing Engineering Research Center of Protein and Antibody, Sinocelltech Ltd., Beijing 100176, China
Gui Qian
Beijing Engineering Research Center of Protein and Antibody, Sinocelltech Ltd., Beijing 100176, China
Xuxin Tian
Beijing Engineering Research Center of Protein and Antibody, Sinocelltech Ltd., Beijing 100176, China
Liangzhi Xie
Beijing Engineering Research Center of Protein and Antibody, Sinocelltech Ltd., Beijing 100176, China
The Omicron EG.5 lineage of SARS-CoV-2 is currently on a trajectory to become the dominant strain. This phase 2 study aims to evaluate the immunogenicity of SCTV01E-2, a tetravalent protein vaccine, with a specific emphasis on its immunogenicity against Omicron EG.5, comparing it with its progenitor vaccine, SCTV01E (NCT05933512). As of 12 September 2023, 429 participants aged ≥18 years were randomized into the groups SCTV01E (N = 215) and SCTV01E-2 (N = 214). Both vaccines showed increases in neutralizing antibody (nAb) against Omicron EG.5, with a 5.7-fold increase and a 9.0-fold increase in the SCTV01E and SCTV01E-2 groups 14 days post-vaccination, respectively. The predetermined statistical endpoints were achieved, showing that the geometric mean titer (GMT) of nAb and the seroresponse rate (SRR) against Omicron EG.5 were significantly higher in the SCTV01E-2 group than in the SCTV01E group. Additionally, SCTV01E and SCTV01E-2 induced a 5.5-fold and a 5.9-fold increase in nAb against XBB.1, respectively. Reactogenicity was generally mild and transient. No vaccine-related serious adverse events (SAEs), adverse events of special interest (AESIs), or deaths were reported. In summary, SCTV01E-2 elicited robust neutralizing responses against Omicron EG.5 and XBB.1 without raising safety concerns, highlighting its potential as a versatile COVID-19 vaccine against SARS-CoV-2 variants.
