Neutralizing activity of a third dose of CoronaVac against Omicron subvariants within a 20-month follow-up study

Cheng Cao; Qin Guo; Yaping Dai; Junfeng Jiang; Min Liu; Tuo Ji; Pengcheng Zhou; Fang Gong

doi:10.1080/21645515.2023.2242217

Neutralizing activity of a third dose of CoronaVac against Omicron subvariants within a 20-month follow-up study

Hum Vaccin Immunother. 2023 Aug 1;19(2):2242217. doi: 10.1080/21645515.2023.2242217.

Authors

Cheng Cao^{1

2}, Qin Guo³, Yaping Dai⁴, Junfeng Jiang^{1

2}, Min Liu³, Tuo Ji^{1

5}, Pengcheng Zhou^{3

6}, Fang Gong^{1

2

3}

Affiliations

¹ Department of Laboratory Medicine, Jiangnan University Medical Center, Wuxi, JS, China.
² Wuxi School of Medicine, Jiangnan University, Wuxi, JS, China.
³ Department of Laboratory Medicine, Affiliated Hospital of Jiangnan University, Wuxi, JS, China.
⁴ Department of Laboratory Medicine, The Fifth People's Hospital of Wuxi, Wuxi, JS, China.
⁵ Department of Central Laboratory, The Second People's Hospital of Lianyungang City (Cancer Hospital of Lianyungang), Lianyungang, JS, China.
⁶ Translational Research Institute, The University of Queensland Diamantina Institute, Brisbane, Australia.

Abstract

The durability of antibody responses induced by the three-dose of CoronaVac vaccination, especially against SARS-CoV-2 Omicron subvariants, remains unclear. Here in our study, 160 plasma samples from 32 healthy individuals who received three doses of CoronaVac were longitudinally tracked for a period of 20 months. The results showed that a third homologous dose of CoronaVac efficiently increased the SARS-CoV-2 IgG and neutralizing antibody titers and enhanced neutralization activity against Omicron subvariants. The levels of IgG and neutralizing antibody declined from peak levels but remained detectable in most subjects over the course of the next 10-12 months. However, most of the individuals kept neutralizing titers against ancestral Wuhan-Hu-1, while they lost their neutralizing activities against Omicron B.1.1.529, BA.2, BA.4/BA.5, and BA.2.75.2 subvariants at 10-12 months post the third vaccination. Our results suggest that a fourth dose of vaccine may be necessary for uninfected individuals to confer higher neutralization against emerging Omicron subvariants.

Keywords: COVID-19 vaccine; CoronaVac; Omicron subvariants; SARS-CoV-2; neutralizing antibodies.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Antibodies, Neutralizing
Antibodies, Viral
COVID-19* / prevention & control
Follow-Up Studies
Humans
Immunoglobulin G
SARS-CoV-2

Substances

sinovac COVID-19 vaccine
Antibodies, Neutralizing
Antibodies, Viral
Immunoglobulin G

Grants and funding

This work was supported by the National Natural Science Foundation of China under grant [numbers 82270034, 82101920], Jiangsu Province “333” Project under grant [number BRA2019152], and Top Talent Support Program for young and middle-aged people of Wuxi Health Committee under grant [number BJ2020059].