1. Immunogenicity of mRNA vs. BBV152 vaccine boosters against Omicron subvariants: Final results from Phase B of the PRIBIVAC study, a randomized clinical trial.
- Author
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Poh XY, Torres-Ruesta A, Yoong T, Wong N, Tan CW, Rouers A, Chavatte JM, Goh YS, Rao S, Chia PY, Ong SWX, Lee TH, Sadarangani SP, Lin RJH, Neo V, Kam IKJ, Huang Y, Hor PX, Loh CY, Yeoh AY, Lim DRX, Chia W, Ren EC, Lin RTP, Fong SW, Renia L, Lye DC, Wang LF, Ng LFP, and Young BE
- Subjects
- Humans, Female, Male, Adult, Middle Aged, Vaccines, Inactivated immunology, Vaccines, Inactivated administration & dosage, mRNA Vaccines immunology, Young Adult, Immunity, Humoral, Immunity, Cellular, Vaccines, Synthetic immunology, Vaccines, Synthetic administration & dosage, COVID-19 Vaccines immunology, COVID-19 Vaccines administration & dosage, SARS-CoV-2 immunology, SARS-CoV-2 genetics, Antibodies, Viral blood, Antibodies, Viral immunology, COVID-19 prevention & control, COVID-19 immunology, Immunization, Secondary methods, Antibodies, Neutralizing blood, Antibodies, Neutralizing immunology, Immunogenicity, Vaccine, Spike Glycoprotein, Coronavirus immunology, Spike Glycoprotein, Coronavirus genetics
- Abstract
Background: BBV152 (Covaxin™) is a whole-virion inactivated SARS-CoV-2 vaccine mixed with an immune adjuvant. We aimed to compare immune responses after booster vaccination with heterologous BBV152 versus homologous mRNA vaccine., Methods: We conducted a randomized, participant-blinded, controlled trial. Fifty mRNA-vaccinated participants were enrolled and randomized to receive an mRNA booster (n = 26) or BBV152 (n = 24). Blood samples were collected pre-vaccination, and at Day 7, 28, 180 and 360 post-booster for analysis of humoral and cellular immune responses. Primary end point was the SARS-CoV-2 anti-spike antibody titer at day 28., Results: Recruitment began in January 2022 and was terminated early due to the BBV152 group meeting pre-specified criteria for futility. At Day 28 post-boost, mean SARS-CoV-2 spike antibody titers were lower with BBV152 (2004 IU/mL; 95 % confidence interval [CI], 1132-3548) vs mRNA (26,669 IU/mL; 95 % CI, 21,330-33,266; p < 0.0001), but comparable levels of spike-specific CD4 and cytotoxic T-cells were observed. Anti-spike antibody titers remained significantly different at Day 180: BBV152 4467 IU/mL (95 % CI, 1959-10,186) vs mRNA 20,749 IU/mL (95 % CI, 12,303-35,075; p = 0.0017). Levels of surrogate virus neutralizing antibodies against ancestral and Omicron subvariants BA.1 and BA.2 were significantly higher among mRNA recipients at Day 180, including after adjusting for intercurrent infection. By Day 360, anti-spike antibody titers and neutralizing antibody levels against Omicron subvariants became similar between vaccine groups. By the end of the study, 16 in each arm (mRNA 64 % and BBV152 69.6 %) had breakthrough infections and time to COVID-19 infection between vaccine groups were similar (p = 0.63)., Conclusions: Wild-type SARS-CoV-2 anti-spike antibody titer and surrogate virus neutralizing test levels against wild-type SARS-CoV-2 and Omicron subvariants BA.1/BA.2/BA.5 were significantly higher at Day 28 and 180 in individuals who received booster vaccination with an mRNA vaccine compared with BBV152., Clinical Trial Registration Number: NCT05142319., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)
- Published
- 2024
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