Immune Responses of a Novel Bi-Cistronic SARS-CoV-2 DNA Vaccine Following Intradermal Immunization With Suction Delivery

SARS-CoV-2 is the third pathogenic coronavirus to emerge since 2000. Experience from prior outbreaks of SARS-CoV and MERS-CoV has demonstrated importance both humoral cellular immunity clinical outcome, precepts that have been recapitulated for SARS-CoV-2. Despite unprecedented rapid development deployment vaccines against SARS-CoV-2, more are needed meet global demand guard immune evasion by newly emerging variants. Here we describe pGO-1002, a novel bi-cistronic synthetic DNA vaccine encodes consensus sequences two antigens, Spike ORF3a. Mice immunized with pGO-1002 developed responses including antibodies capable neutralizing infection isolate. Rats intradermal (ID) injection followed application suction our GeneDerm device also included RBD-ACE2 blocking as well robust antigens. Significantly, in Syrian hamster vaccination challenge model, ID+GeneDerm-assisted prevented viral replication lungs significantly reduced nares hamsters challenged either an ancestral strain or B.1.351 (Beta) variant concern. Furthermore, vaccinated sera inhibited virus-mediated cytopathic effects vitro. These data establish immunogenicity candidate which induces potent ORF3a antigens may provide greater protection