Vaccine protection against the SARS-CoV-2 Omicron variant in macaques
Abishek Chandrashekar, Jingyou Yu, Katherine McMahan, Catherine Jacob-Dolan, Jinyan Liu, Xuan He, David Hope, Tochi Anioke, Julia Barrett, Benjamin Chung, Nicole P. Hachmann, Michelle A. Lifton, Jessica Miller, Olivia Powers, Michaela Sciacca, Daniel Sellers, Mazuba Siamatu, Nehalee Surve, Haley VanWyk, Huahua Wan, Cindy Wu, Laurent Pessaint, Daniel Valentin, Alex Van Ry, Jeanne Muench, Mona Boursiquot, Anthony Cook, Jason Velasco, Elyse Teow, Adrianus C. M. Boon, Mehul S. Suthar, Neharika Jain, Amanda J. Martinot, Mark G. Lewis, Hanné Andersen, Dan H. Barouch
Abstract
The rapid spread of the SARS-CoV-2 Omicron (B.1.1.529) variant, including in highly vaccinated populations, has raised important questions about the efficacy of current vaccines. In this study, we show that the mRNA-based BNT162b2 vaccine and the adenovirus-vector-based Ad26.COV2.S vaccine provide robust protection against high-dose challenge with the SARS-CoV-2 Omicron variant in cynomolgus macaques. We vaccinated 30 macaques with homologous and heterologous prime-boost regimens with BNT162b2 and Ad26.COV2.S. Following Omicron challenge, vaccinated macaques demonstrated rapid control of virus in bronchoalveolar lavage, and most vaccinated animals also controlled virus in nasal swabs. However, 4 vaccinated animals that had moderate Omicron-neutralizing antibody titers and undetectable Omicron CD8+ T cell responses failed to control virus in the upper respiratory tract. Moreover, virologic control correlated with both antibody and T cell responses. These data suggest that both humoral and cellular immune responses contribute to vaccine protection against a highly mutated SARS-CoV-2 variant.