Journal Article

Boosting with an aerosolized Ad5-nCoV elicited robust immune responses in inactivated COVID-19 vaccines recipients

Wang, Busen, Xu, Jinghan, Zhang, Xianwei, Zhao, Xiaofan, Li, Kailiang, Fan, Pengfei, Zhang, Zhe, Fu, Kefan, Long, Pengwei, Shang, Jin, Liu, Yawei, Song, Xiaohong, Wang, Yudong, Zhang, Jinlong, Zhu, Tao, Li, Yao, Zhao, Zhenghao, Yang, Yilong, Lv, Peng, Sun, Yufa, Hou, Lihua, Li, Yaohui, Qiu, Ziyu, Zhang, Guanying, Shao, Fangze, Liu, Shuling, Chen, Wei, Zhang, Yue, Zhang, Jipeng, Hao, Meng, Wu, Shipo

2023

Overview

IntroductionThe SARS-CoV-2 Omicron variant has become the dominant SARS-CoV-2 variant and exhibits immune escape to current COVID-19 vaccines, the further boosting strategies are required.MethodsWe have conducted a non-randomized, open-label and parallel-controlled phase 4 trial to evaluate the magnitude and longevity of immune responses to booster vaccination with intramuscular adenovirus vectored vaccine (Ad5-nCoV), aerosolized Ad5-nCoV, a recombinant protein subunit vaccine (ZF2001) or homologous inactivated vaccine (CoronaVac) in those who received two doses of inactivated COVID-19 vaccines.ResultsThe aerosolized Ad5-nCoV induced the most robust and long-lasting neutralizing activity against Omicron variant and IFNg T-cell response among all the boosters, with a distinct mucosal immune response. SARS-CoV-2-specific mucosal IgA response was substantially generated in subjects boosted with the aerosolized Ad5-nCoV at day 14 post-vaccination. At month 6, participants boosted with the aerosolized Ad5-nCoV had remarkably higher median titer and seroconversion of the Omicron BA.4/5-specific neutralizing antibody than those who received other boosters.DiscussionOur findings suggest that aerosolized Ad5-nCoV may provide an efficient alternative in response to the spread of the Omicron BA.4/5 variant.Clinical trial registrationhttps://www.chictr.org.cn/showproj.html?proj=152729, identifier ChiCTR2200057278.

• Publisher: Frontiers Media SA,Frontiers Media S.A
• Subject: Ad5-nCoV vaccine / Adenoviruses / aerosolized / Antibodies / BA.5 Omicron Variant / COVID-19 vaccines / Immune response / Immunoglobulin A / Immunology / Lymphocytes T / Mucosal immunity / neutralizing Abs / Plasmids / Proteins / saliva IgA / SARS-CoV-2 / Seroconversion / Severe acute respiratory syndrome coronavirus 2