The Ad5/35 Platform-Based Vaccines for SARS-CoV-2: A Strategy to Counter Evolving Variants 2324

Abstract Description The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus has continuously and rapidly evolved, and it causes persistent global health threats with increased morbidity and mortality. Given the pace of viral mutation, developing vaccines that target newly emerging variants is essential to enhance protection against circulating and potential future strains. We previously developed AdCLD-CoV19-1 OMI, an Ad5/35 platform-based non-replicating recombinant adenoviral vector that encodes the spike protein of an early Omicron variant, which is currently undergoing the follow-up period of phase III clinical trials. To further address emerging variants, we constructed the library of variant-specific vaccines using our Ad5/35 platform and developed the strategy for the rapid adaptation of our vaccines. This approach integrates phylogenetic analysis using spike protein sequences with antigenic cartography based on neutralization data. Our preclinical studies demonstrate that vaccines tailored with this strategy effectively induce neutralizing antibodies against currently prevalent subvariants. These findings highlight the importance of vaccine development to keep pace with the evolution of SARS-CoV-2 variants and the need for timely updated vaccines to counter new variants. Funding Sources This research was supported by Seoul R&BD Program (BT240041) through the Seoul Business Agency(SBA) funded by The Seoul Metropolitan Government. Topic Categories Vaccines and Immunotherapy (VAC)