Safety, Reactogenicity, and Immunogenicity Study of Heterologous Booster Vaccination of a SARS-CoV-2 Recombinant Protein Nanoparticle Vaccine (GBP510)

The purpose of this study is to assess the safety, reactogenicity and immunogenicity of booster vaccination of a SARS-CoV-2 recombinant protein nanoparticle vaccine (GBP510). (Cohort 1\~5) A total of approximately 550 adults will be divided into 5 cohorts based on primary series vaccines they received - ChAdOx1 nCOV-19, BNT162b2, mRNA-1273, Ad26.COV2.S and heterologous vaccination with ChAdOx1 nCOV-19 \& BNT162b2. (Cohort 6\~7) A total of approximately 220 adults will be divided into 2 cohorts based on primary series \& 1st booster vaccines they received -mRNA vaccines (BNT162b2 or mRNA-1273) and at least more than a single dose of non-mRNA vaccines (ChAdOx1 nCOV-19, Ad26.COV2.S, and NVX-CoV2373) The participants are then randomized at a ratio of 10:1 to either Test Group or Placebo Group. Participants will be subject to follow-up for 12 months after receiving a single booster dose of GBP510 adjuvanted with AS03. Blood sampling for cell-mediated immunity will be undertaken on approximately 20% of the participants in each cohort, who are selected in advance in consideration of the randomization ratio between Test Group and Placebo Group.