Moderna's Booster Demonstrated Higher Antibody Titers Against Tested Virus Variants

Massachusetts-based Moderna, Inc. today announced new, positive 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 µg 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 SpikeVax 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 (95% CI: 1.51-1.90).

One month after the booster, BA.4/5 neutralizing titers were 776 (95% CI: 719, 838) for mRNA-1273.214 and 458 (95% CI: 421, 499) for the currently authorized booster.

The BA.4/5 geometric mean fold rise (GMFR) from pre-booster levels was 6.3-fold (95% CI: 5.7, 6.9) for mRNA-1273.214 recipients, and 3.5-fold (95% CI: 3.2, 3.9) for mRNA-1273 recipients.

Consistent results were demonstrated across subgroups, including in those aged 65 and older.

"Today's update extends the remarkable performance of mRNA-1273.214, demonstrating significantly higher titers against all tested variants, including the BA.4/5 and BA.1 Omicron subvariants, and adds to the largest body of data confirming the superiority of a bivalent approach."

"This superior breadth and durability of the immune response following a bivalent booster have now been shown in multiple Phase 2/3 studies involving thousands of participants," said Stephane Bancel, Chief Executive Officer of Moderna, in a press release issued on July 11, 2022.

"We are working with regulators to advance two bivalent vaccine candidates, mRNA-1273.214 and mRNA-1273.222, based on different market preferences for Omicron subvariants, clinical data requirements, and urgency of starting fall booster campaigns for vulnerable populations."

Moderna stated a second bivalent booster candidate, mRNA 1273.222, is based on the BA.4/5 strain and is being developed consistent with recent U.S. FDA advice.

Both bivalent candidates contain 25 µg of the currently authorized booster (mRNA-1273) and 25 µg of an Omicron subvariant.

Note: This press release was manually curated for mobile readers.