Moderna, Inc., announced new clinical data on its bivalent COVID-19 booster platform including data on the company's first bivalent booster candidate, mRNA-1273.211, which includes mutations found in the Beta variant of concern, several of which have been persistent in more recent variants of concern including Omicron, according to a news release.
A50 µg booster dose ofmRNA-1273.211 demonstrated superiority against Beta, Delta, and Omicron variants of concern one month after administration. Superiority continued six months after administration for Beta and Omicron variants of concern as well. A50 µg booster dose ofmRNA-1273.211 was generally well tolerated with a reactogenicity profile comparable to a booster dose of mRNA-1273 at the 50 µg dose level. The manuscript is available as a preprint through Research Square.
Moderna is developing updated booster candidates to address the continued evolution of the SARS-CoV-2 virus, including monovalent and bivalent candidates targeting multiple variants of concern. The Company's primary focus has been on the bivalent booster approach to maintain high neutralizing antibody titers while improving breadth of immunity to variants. Moderna has multiple bivalent booster candidates that have been evaluated to date, which include mRNA-1273.211 (9 spike protein mutations, based on the Beta variant), and mRNA-1273.214 (32 spike protein mutations, based on the Omicron variant). mRNA-1273.211 includes four mutations and mRNA-1273.214 includes 32 mutations present in the Omicron variant of concern.
A 50 µg booster dose of mRNA-1273.211 met Moderna's objectives for its modified, bivalent booster candidates, including superiority immunogenicity criteria against variants of concern when compared to its currently approved mRNA-1273 booster dose (50 µg). A booster dose of mRNA-1273.211 demonstrated superiority against the ancestral SARS-CoV-2 and the Beta, Delta, and Omicron variants one month after the booster dose and superiority against the ancestral SARS-CoV-2, Beta and Omicron 6 months compared to the booster dose of mRNA-1273. There was a 2.20-fold (95% CI: 1.74, 2.79) and 2.15-fold (95% CI: 1.66, 2.78) increase in the neutralizing antibody titers against Omicron with the mRNA-1273.211 booster dose compared to the mRNA-1273 booster dose at 1 month and 6 months, respectively.
The mRNA-1273.211 booster candidate was generally well tolerated in 300 study participants who received the 50 µg dose and 595 participants who received the 100 µg dose of mRNA-1273.211 (895 participants in total). The 50 µg booster dose of mRNA-1273.211 had a similar incidence of solicited adverse reactions and unsolicited adverse events with the authorized mRNA-1273 booster (50 µg).
The results indicate that the bivalent booster vaccine candidate mRNA-1273.211 at the 50 µg dose level induced higher antibody responses than the 50 µg mRNA-1273 booster, even when the variants were not included in the booster vaccine which, if authorized, would create a new tool as Moderna responds to emerging variants.
Moderna's bivalent prototype and Omicron booster vaccine candidate (mRNA-1273.214) is currently being evaluated in a Phase 2/3 study. The company expects initial data on mRNA-1273.214 in the second quarter of this year to inform selection of its candidate for the Northern Hemisphere fall 2022 booster.