SARS-CoV-2 preS dTM vaccine booster candidates increase functional antibody responses and cross-neutralization against SARS-CoV-2 variants of concern in non-human primates [article]

Vincent Pavot, Catherine Berry, Michael Kishko, Natalie G Anosova, Dean Huang, Tim Tibbitts, Alice Raillard, Sylviane Gautheron, Cindy Gutzeit, Marguerite Koutsoukos, Roman M Chicz, Valerie Lecouturier
2021 bioRxiv   pre-print
The emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants that partly evade neutralizing antibodies has raised concerns of reduced vaccine effectiveness and increased infection. We previously demonstrated in preclinical models and in human clinical trials that our SARS-CoV-2 recombinant spike protein vaccine adjuvanted with AS03 (CoV2 preS dTM-AS03) elicits robust neutralizing antibody responses in naive subjects. Here, the objective was to document the potency of
more » ... rious booster vaccine formulations in macaques previously vaccinated with mRNA or protein subunit vaccine candidates. We show that one booster dose of AS03-adjuvanted CoV2 preS dTM, D614 (parental) or B.1.351 (Beta), in monovalent or bivalent (D614 + B.1.351) formulations, significantly boosted pre-existing neutralizing antibodies and elicited high and stable cross-neutralizing antibodies covering the four known SARS-CoV-2 variants of concern (Alpha, Beta, Gamma and Delta) and, unexpectedly, SARS-CoV-1, in primed macaques. Interestingly, the non-adjuvanted CoV2 preS dTM B.1.351 vaccine formulation also significantly boosted and broadened the neutralizing antibody responses. Our findings show that these vaccine candidates used as a booster have the potential to offer cross-protection against a broad spectrum of variants. This has important implications for vaccine control of SARS-CoV-2 variants of concern and informs on the benefit of a booster with our vaccine candidates currently under evaluation in phase 2 and 3 clinical trials (NCT04762680 and NCT04904549).
doi:10.1101/2021.09.20.461023 fatcat:xqi6qk2j35hoxhm4k2lis54efe