Moderna’s updated COVID-19 vaccine provides a “significant improvement” in neutralizing antibody levels in humans against the latest omicron SARS-CoV-2 subvariants circulating in the US, namely, EG.5 and FL.1.5.1, according to a press release from the company.
The updated booster shot is expected to be authorized and launched in the coming weeks.
Moderna, which reported its take from preliminary clinical trial data, did not release additional study details, including the number of trial participants or the relative increase in neutralizing antibody levels. But the announcement is aimed at easing concerns about whether the fall booster will be enough to match this season’s variants.
“These new results, which show that our updated COVID-19 vaccine generates a strong immune response against the rapidly spreading strains of EG.5 and FL.1.5. 1 and demonstrates our renewed vaccine ability to address the emerging threat of COVID-19,” President of Moderna. Stephen Hoge said in the press release.
The shots were designed against the then reigning omicron subvariant, XBB.1.5. In June, an advisory panel for the Food and Drug Administration determined that a shot targeting an XBB variant, specifically XBB.1.5, was the best choice for the 2023-2024 season.
Both EG.5 and FL.1.5.1 are in the XBB family, with EG.5 related to XBB.1.9.2 and FL.1.5.1 related to XBB.1.9.1. (Some of these subvariants have been given unofficial, mythological nicknames by a social media scientist. Ars will only use the established Pango Lineage classification system endorsed by the World Health Organization and other major health organizations to describe the different generations.)
According to the latest data from the Centers for Disease Control and Prevention, EG.5 is estimated to account for about 21 percent of circulating SARS-CoV-2 viruses, while FL.1.5.1 accounts for about 13 percent.
Pfizer also said that its XBB.1.5-targeted booster also stimulated neutralizing antibodies against EG.5 in a mouse study, according to a report from Reuters.