Article
作者: Heppner, D Gray ; Malherbe, Delphine C ; Hung, Chung Ho ; Subramani, Chandru ; Liu, Zhi ; Lin, Yi Ling ; Ding, Shuang ; Chen, Tony ; Peng, Wen-Jiun ; Hou, Kou-Liang ; Kuo, Hui-Kai ; Periasamy, Sivakumar ; Wang, Chang Yi ; Lin, Feng ; Huang, Juin-Hua ; Wang, Shixia ; Bukreyev, Alexander ; Hellerstein, Michael ; Rumyantsev, Alexander ; Shih, Zhonghao ; Lin, Ed ; Kuo, Be-Shen ; Wang, Min-Sheng ; Ryan, Valorie ; Guirakhoo, Farshad ; Liu, Yaw-Jen ; Wu, Huang-Ting ; Hu, Mei Mei ; Kuzmina, Natalia ; Xia, Wei Guo ; Yang, Ya-Ting ; Cheng, Jennifer ; Monath, Thomas P ; Jiang, Ming-Han ; Chen, Hui-Jung
The development of safe and effective vaccines to respond to COVID-19 pandemic/endemic remains a priority. We developed a novel subunit protein-peptide COVID-19 vaccine candidate (UB-612) composed of: (i) receptor binding domain of SARS-CoV-2 spike protein fused to a modified single-chain human IgG1 Fc; (ii) five synthetic peptides incorporating conserved helper and cytotoxic T lymphocyte (Th/CTL) epitopes derived from SARS-CoV-2 structural proteins (three from S2 subunit, one from membrane and one from nucleocapsid), and one universal Th peptide; (iii) aluminum phosphate as adjuvant. The immunogenicity and protective immunity induced by UB-612 vaccine were evaluated in four animal models: Sprague-Dawley rats, AAV-hACE2 transduced BALB/c mice, rhesus and cynomolgus macaques. UB-612 vaccine induced high levels of neutralizing antibody and T-cell responses, in all animals. The immune sera from vaccinated animals neutralized the SARS-CoV-2 original wild-type strains and multiple variants of concern, including Delta and Omicron. The vaccination significantly reduced viral loads, lung pathology scores, and disease progression after intranasal and intratracheal challenge with SARS-CoV-2 in mice, rhesus and cynomolgus macaques. UB-612 has been tested in primary regimens in Phase 1 and Phase 2 clinical studies and is currently being evaluated in a global pivotal Phase 3 clinical study as a single dose heterologous booster.