Immunogenicity consistency and safety with different production scales of recombinant adenovirus type-5 vectored COVID-19 vaccine in healthy adults: a randomized, double-blinded, immunobridging trial

• Published in: Expert review of vaccines Vol. 22; no. 1; pp. 662 - 670
• Main Authors: Wu, Yan-Fei, Wei, Ming-Wei, Wang, Rui-Jie, Guo, Xi-Ling, Pan, Hong-Xing, Gao, Ya-Chun, Li, Xiao-Long, Wang, Xue, Ma, Xiao-Min, Wan, Peng, Zhou, Li, Zhu, Ya-Wen, Li, Jing-Xin, Zhu, Feng-Cai
• Format: Journal Article
• Language: English
• Published: England Taylor & Francis 31.12.2023; Taylor & Francis Group
• Subjects: Ad5-nCov; Adenoviridae - genetics; Adolescent; Adult; Antibodies, Neutralizing; Antibodies, Viral; clinical trial; COVID-19 - prevention & control; COVID-19 vaccine; COVID-19 Vaccines - immunology; Humans; Immunogenicity consistency; Immunogenicity, Vaccine; Middle Aged; Nab against live SARS-CoV-2; Young Adult; clinical trial; COVID-19 vaccine; Ad5-nCov; Immunogenicity consistency; Nab against live SARS-CoV-2
• ISSN: 1476-0584; 1744-8395
• DOI: 10.1080/14760584.2023.2234997

The certification of immunogenicity consistency at different production scales is indispensable for the quality control of vaccines. A randomized, double-blind immunobridging trial in healthy adults aged 18-59 was divided into Scale A (50 L and 800 L) and Scale B (50 L and 500 L) based on vaccine manufacturing scales. Eligible participants in Scale A were randomly assigned to receive the single-dose recombinant adenovirus type-5 vectored COVID-19 vaccine (Ad5-nCoV) of different scales at a 1:1 ratio, as was Scale B. The primary endpoint was the geometric mean titer (GMT) of anti-live SARS-CoV-2-specific neutralizing antibodies (NAb) 28 days post-vaccination. 1,012 participants were enrolled, with 253 (25%) per group. The post-vaccination GMTs of NAb were 10.72 (95% CI: 9.43, 12.19) and 13.23 (11.64, 15.03) in Scale A 50 L and 800 L, respectively; 11.64 (10.12, 13.39) and 12.09 (10.48, 13.95) in Scale B 50 L and 500 L, respectively. GMT ratios in Scale A and B have a 95% CI of 0.67-1.5. Most adverse reactions were mild or moderate. 17 of 18 participants reported non-vaccination-related serious adverse reactions. The Ad5-nCoV in the scale-up production of 500 L and 800 L showed consistent immunogenicity with the original 50 L production scale, respectively.