Immunogenicity assessments
VIRUS
Anti-S IgG antibodies against prototype strain (Wuhan) were assessed using validated enzyme-linked immunosorbent assay (ELISA) and nAbs were assessed by validated microneutralization (MN) assay using wild type virus (Ancestral strain: SARS-CoV-2 hCoV-19/Australia/VIC01/2020, GenBank MT007544.1) with an inhibitory concentration of 50% (MNThe lower limit of quantification (LLOQ) for anti-S IgG ELISA assay was 200 ELISA units per mL (EU/mL), with titers below this level documented as 100 EU/mL. The LLOQ for MN assay was a titer of 20, with titers below this level documented as 10. The LLOQ for hACE2 receptor binding inhibition assay was a titer of 10, with titers below this level documented as 5. Details of assays are included in the Supplementary appendix.Immunogenicity testing was performed in compliance with Good Clinical Laboratory Practice (GCLP) requirements at Novavax, USA (Anti-S IgG and hACE2 receptor binding inhibition assay), at 360biolabs, Australia (nAbs) and at NARI-ICMR, India (CMI).