On Jul. 11, 2022, Moderna announced new clinical data on its bivalent Omicron (BA.1) booster candidate, mRNA-1273.214. One month after administration in previously vaccinated and boosted participants, a 50 ﾵg booster dose of mRNA-1273.214 elicited significantly higher neutralizing antibody responses against the Omicron subvariants BA.4 and BA.5 compared to the currently authorized booster (mRNA-1273) regardless of prior infection status or age (adults over 18, greater or less than 65 years old).

Among participants without prior infection, bivalent mRNA-1273.214 resulted in significantly higher neutralizing titers against BA.4/5 compared to the currently authorized booster, with a geometric mean ratio of 1.69. One month after booster, BA.4/5 neutralizing titers were 776 for mRNA-1273.214 and 458 for the currently authorized booster. The BA.4/5 geometric mean fold rise (GMFR) from pre-booster levels was 6.3-fold for mRNA-1273.214 recipients, and 3.5-fold for mRNA-1273 recipients. Consistent results were demonstrated across subgroups, including in those age 65 and older. The complete data had been submitted for peer reviewed publication and shared with regulators.