Immunogenicity and reactogenicity after heterologous prime-boost vaccination with CoronaVac and ChAdox1 nCov-19 (AZD1222) vaccines

• Main Authors: Guy Cohen (Author), Pawornrath Jungsomsri (Author), Jirath Sangwongwanich (Author), Kriangkrai Tawinprai (Author), Taweegrit Siripongboonsitti (Author), Thachanun Porntharukchareon (Author), Kasiruck Wittayasak (Author), Nawarat Thonwirak (Author), Kamonwan Soonklang (Author), Gaidganok Sornsamdang (Author), Chirayu Auewarakul (Author), Nithi Mahanonda (Author)
• Format: Book
• Published: Taylor & Francis Group, 2022-11-01T00:00:00Z.
• Subjects: article
• Online Access: Connect to this object online.

Summary

Mass vaccination with a safe and effective vaccine may be the best way to control the COVID-19 pandemic. Heterologous prime-boost vaccination with the CoronaVac and AZD1222 vaccines may increase the immunogenicity elicited by either vaccine alone. This study sought to compare the immunogenicity of a heterologous CoronaVac and AZD1222 prime-boost with a homologous CoronaVac prime-boost. From July 13 to September 2, 2021, 88 participants were enrolled in the study. Half (n = 44) of the participants were assigned to the AZD1222/CoronaVac cohort and half were assigned to the CoronaVac/AZD1222 cohort. Both cohorts had a prime-boost interval of 4 weeks. A control group of 136 health care personnel who received the homologous CoronaVac/CoronaVac prime-boost was matched by age and sex to the experimental cohorts. The primary endpoint was the geometric mean ratio (GMR) of the anti-receptor binding domain (RBD) antibody concentration 4 weeks after the booster dose was administered. The CoronaVac/CoronaVac cohort served as the reference group. Baseline age and sex were similar, and the median age was 42.5 years. The GMR was 2.58 (95% confidence interval [CI] 1.80-3.71) and 8.69 (95% CI 6.05-12.47) in the AZD1222/CoronaVac and CoronaVac/AZD1222 cohorts, respectively. Reactogenicity was similar following prime and booster doses with the same vaccine. Findings indicated that the heterologous CoronaVac and AZD1222 prime-boost combination elicited a more robust immune response than the homologous CoronaVac prime-boost. While both heterologous prime-boost combinations showed similar reactogenicity, the immunogenicity of the CoronaVac/AZD1222 cohort was higher, indicating that the order of prime-boost vaccine administration was important.

Item Description

2164-5515
2164-554X
10.1080/21645515.2022.2052525