Superior antibody and membrane protein-specific T-cell responses to CoronaVac by intradermal versus intramuscular routes in adolescents

• DOI: 10.1007/s12519-023-00764-0
• Publication Date: 2023-12-12T07:02:31Z
• Authors: Jaime S. Rosa Duque; Samuel M. S. Cheng; Carolyn A. Cohen; Daniel Leung; Xiwei Wang; Xiaofeng Mu; Yuet Chung; Tsun Ming Lau; Manni Wang; Wenyue Zhang; Yanmei Zhang; Howard H. W. Wong; Leo C. H. Tsang; Sara Chaothai; Tsz Chun Kwan; John K. C. Li; Karl C. K. Chan; Leo L. H. Luk; Jenson C. H. Ho; Wing Yan Li; Amos M. T. Lee; Jennifer H. Y. Lam; Sau Man Chan; Wilfred H. S. Wong; Issan Y. S. Tam; Masashi Mori; Sophie A. Valkenburg; Malik Peiris; Wenwei Tu; Yu Lung Lau
• Keywords: Intradermal injection

Abstract Background Optimising the immunogenicity of COVID-19 vaccines to improve their protection against disease is necessary. Fractional dosing by intradermal (ID) administration has been shown be equally immunogenic as intramuscular (IM) for several vaccines, but ID inactivated whole severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) at full dose unknown. This study (NCT04800133) investigated superiority antibody and T-cell responses full-dose CoronaVac over IM in adolescents. Methods Participants aged 11–17 years received two doses or vaccine, followed 3rd 13–42 days later. Humoral cellular outcomes were measured post-dose (IM-CC versus ID-CC) 3 (IM-CCC ID-CCC). Doses administered 173 104 adolescents, respectively. Results Spike protein (S) immunoglobulin G (IgG), S-receptor-binding domain (RBD) IgG, S IgG Fcγ receptor IIIa (FcγRIIIa)-binding, SNM [sum individual (S), nucleocapsid (N), membrane (M) peptide pool]-specific interleukin-2 (IL-2) + CD4 , SNM-specific IL-2 CD8 S-specific N-specific M-specific fulfilled superior non-inferior criteria ID-CC compared IM-CC, whereas avidity was inferior. For ID-CCC, S-RBD surrogate virus neutralisation test, 90% plaque reduction titre (PRNT90), PRNT50, avidity, FcγRIIIa-binding, interferon-γ IM-CCC. The estimated vaccine efficacies 49%, 52%, 66% 79% ID-CC, IM-CCC groups reported more local, mild adverse reactions. Conclusion first demonstrate SARS-CoV-2 vaccination serves basis future research vaccines. Graphical abstract