The immunogenicity of an extended dosing interval of BNT162b2 against SARS-CoV-2 Omicron variant among healthy school-aged children, a randomized controlled trial
Issued Date
2023-05-01
Resource Type
ISSN
12019712
eISSN
18783511
Scopus ID
2-s2.0-85150042099
Pubmed ID
36841501
Journal Title
International Journal of Infectious Diseases
Volume
130
Start Page
52
End Page
59
Rights Holder(s)
SCOPUS
Bibliographic Citation
International Journal of Infectious Diseases Vol.130 (2023) , 52-59
Suggested Citation
Chantasrisawad N., Techasaensiri C., Kosalaraksa P., Phongsamart W., Tangsathapornpong A., Jaru-Ampornpan P., Sophonphan J., Suntarattiwong P., Puthanakit T. The immunogenicity of an extended dosing interval of BNT162b2 against SARS-CoV-2 Omicron variant among healthy school-aged children, a randomized controlled trial. International Journal of Infectious Diseases Vol.130 (2023) , 52-59. 59. doi:10.1016/j.ijid.2023.02.017 Retrieved from: https://repository.li.mahidol.ac.th/handle/20.500.14594/82775
Title
The immunogenicity of an extended dosing interval of BNT162b2 against SARS-CoV-2 Omicron variant among healthy school-aged children, a randomized controlled trial
Author's Affiliation
Siriraj Hospital
Faculty of Medicine, Khon Kaen University
King Chulalongkorn Memorial Hospital
Faculty of Medicine Ramathibodi Hospital, Mahidol University
Faculty of Medicine, Thammasat University
Thailand National Center for Genetic Engineering and Biotechnology
Queen Sirikit National Institute of Child Health
Faculty of Medicine, Chulalongkorn University
Faculty of Medicine, Khon Kaen University
King Chulalongkorn Memorial Hospital
Faculty of Medicine Ramathibodi Hospital, Mahidol University
Faculty of Medicine, Thammasat University
Thailand National Center for Genetic Engineering and Biotechnology
Queen Sirikit National Institute of Child Health
Faculty of Medicine, Chulalongkorn University
Other Contributor(s)
Abstract
Objectives: To evaluate the immunogenicity of an extended interval regimen of BNT162b2 among healthy school-age children. Methods: A randomized-control trial conducted among healthy Thai children aged 5-11 years. Participants received two doses of BNT162b2 with an 8-week (extended dosing) vs 3-week interval. Immunogenicity was determined by neutralization test (NT) against the Omicron variant, surrogate virus NT (sVNT; BA.1, % inhibition), and pseudovirus NT (BA.2, the half-maximal inhibition dilution or ID50). The third dose was offered to participants who had sVNT <68% inhibition. The immunogenicity outcome was evaluated at 14 days after the second and third doses. Results: During February to April 2022, 382 children with a median age (interquartile range) of 8.4 years (6.6-10.0) were enrolled. At 14 days, after two doses of BNT162b2, the geometric means of sVNT in 8-week vs 3-week interval groups were 49.6 (95% confidence interval [CI] 44.8-54.9) vs 16.5 (95% CI 13.0-20.9), with a geometric means ratio of 3.0 (95% CI 2.4-3.8). Among 102 participants who received the third dose at a median of 15 weeks from the second dose, the geometric means of sVNT increased to 73.3 (95% CI 69.0-77.8) and pseudovirus NT increased to 326 (95% CI 256-415). Conclusion: The extended 8-week interval regimen of BNT162b2 induced higher neutralizing antibodies than a standard 3-week interval regimen. The third dose induced high neutralizing antibodies against the Omicron variant.