(CNN) Biotechnology company Moderna announced Monday that preliminary data suggests its half-dose booster shot increased antibody levels against the Omicron coronavirus variant -- 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 this dose increased antibody levels 37-fold, compared with the levels seen when a fully vaccinated person does not receive a booster, and a 100-microgram dose increased antibody levels 83-fold.
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.
"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.
It's now up to US public health authorities to consider whether Moderna's coronavirus vaccine booster should be given at a larger dose, Dr. Stephen Hoge, president of the company, said Monday.
"The decision of whether to deploy 100 micrograms or a higher dose is really one for public health agencies at this point. We are just providing the data, and obviously we'll share it with everybody so that they can make that determination," Hoge said during a company conference call.
Moderna spokesperson Colleen Hussey confirmed to CNN in an emailed statement Monday that the company is "sharing the data with regulators as they begin to assess if any changes to the authorized boosters need to be made."
Moderna's current coronavirus vaccine booster is authorized for emergency use for people 18 and older in the United States and given as a half-dose at 50 micrograms, and it's authorized at the 100-microgram dose for people who are severely immunocompromised, the statement noted.
According to the US Centers for Disease Control and Prevention, about 32% of fully vaccinated adults -- almost 60 million people -- have gotten a booster dose. More than 26.7 million of them have received a Moderna booster, according to CDC data.
Separately, "we're going to continue to advance an Omicron-specific booster into clinical trials in early 2022," Hoge said Monday.
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 last week.
"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."