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Moderna: Initial booster data shows good results on omicron

FILE - A vial of the Moderna COVID-19 vaccine is seen during a vaccination clinic at the Norristown Public Health Center in Norristown, Pa., Tuesday, Dec. 7, 2021. Moderna said Monday, Dec. 20, 2021 that a booster dose of its COVID-19 vaccine should offer protection against the rapidly spreading omicron variant. (AP Photo/Matt Rourke, File)
FILE - A vial of the Moderna COVID-19 vaccine is seen during a vaccination clinic at the Norristown Public Health Center in Norristown, Pa., Tuesday, Dec. 7, 2021. Moderna said Monday, Dec. 20, 2021 that a booster dose of its COVID-19 vaccine should offer protection against the rapidly spreading omicron variant. (AP Photo/Matt Rourke, File) FILE - A vial of the Moderna COVID-19 vaccine is seen during a vaccination clinic at the Norristown Public Health Center in Norristown, Pa., Tuesday, Dec. 7, 2021. Moderna said Monday, Dec. 20, 2021 that a booster dose of its COVID-19 vaccine should offer protection against the rapidly spreading omicron variant. (AP Photo/Matt Rourke, File)

Moderna said Monday that a booster dose of its COVID-19 vaccine should offer protection against the rapidly spreading omicron variant.

Moderna said lab tests showed the half-dose booster shot increased by 37 times the level of so-called neutralizing antibodies able to fight omicron.

And a full-dose booster was even stronger, triggering an 83-fold jump in antibody levels, although with an increase in the usual side effects, the company said. While half-dose shots are being used for most Moderna boosters, a full-dose third shot has been recommended for people with weakened immune systems.

Moderna announced the preliminary laboratory data in a press release and it hasn’t yet undergone scientific review. But testing by the U.S. National Institutes of Health, announced last week by Dr. Anthony Fauci, found a similar jump.

Pfizer’s testing likewise found its COVID-19 vaccine triggered a similarly big jump in omicron-fighting antibodies. The vaccines made by Pfizer and by Moderna, both made with mRNA technology, are used by many countries around the world to fight the coronavirus.