Moderna booster shot increases antibody levels against omicron, company says

FILE - In this Dec. 15, 2020, file photo, a sign for Moderna, Inc. hangs on its headquarters in Cambridge, Mass. The U.S. is poised to give the green light as early as Friday, Dec. 18, to a second COVID-19 vaccine, a critical new weapon against the surging coronavirus. Doses of the vaccine developed by Moderna Inc. and the National Institutes of Health will give a much-needed boost to supplies as the biggest vaccination effort in the nation’s history continues. (AP Photo/Elise Amendola, File)

(CNN) — Biotechnology company Moderna announced Monday that preliminary data suggests its half-dose booster shot increased antibody levels against omicron compared with the levels seen when a fully vaccinated person does not receive a booster — and a larger-sized dose of the booster increases antibody levels even more.

Currently, Moderna’s booster is administered as a 50-microgram dose. The company announcement noted that its 50-microgram booster dose increased antibody levels 37-fold and a 100-microgram booster dose increased antibody levels 83-fold compared with levels seen before a booster. It remains unclear what these increases mean as far as how well the booster doses clinically work against omicron.

But in the company’s statement, CEO Stéphane Bancel called the data “reassuring.”

“The dramatic increase in COVID-19 cases from the Omicron variant is concerning to all. However, these data showing that the currently authorized Moderna COVID-19 booster can boost neutralizing antibody levels 37-fold higher than pre-boost levels are reassuring,” Bancel said in the announcement.

“To respond to this highly transmissible variant, Moderna will continue to rapidly advance an Omicron-specific booster candidate into clinical testing in case it becomes necessary in the future. We will also continue to generate and share data across our booster strategies with public health authorities to help them make evidence-based decisions on the best vaccination strategies against SARS-CoV-2.”

SARS-CoV-2 is the name of the coronavirus that causes COVID-19.

According to the US Centers for Disease Control and Prevention, about 32% of fully vaccinated adults have received a booster dose so far. Separately, Moderna and other vaccine makers have said that they are working on variant-specific booster shots as well.

COVID-19 booster shots can help improve protection against the Omicron coronavirus variant and there is no need for a variant-specific booster dose at this time, Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, said during a virtual White House briefing on Wednesday.

“A number of studies have been done throughout the country and the world to take a look at how we might prepare in the context of vaccinations,” Fauci said.

“The message remains clear: If you are unvaccinated, get vaccinated,” added Fauci, the chief medical adviser to President Biden. “And particularly in the arena of omicron, if you are fully vaccinated, get your booster shot.”