Moderna says its booster significantly raises the level of antibodies to thwart Omicron.

A booster shot of the Moderna coronavirus vaccine significantly raises the level of antibodies that can thwart the Omicron variant, the company announced on Monday.

The news arrives as Omicron rapidly advances across the world, and most coronavirus vaccines seem unable to stave off infection from the highly contagious variant.

Moderna’s results show that the currently authorized booster dose of 50 micrograms — half the dose given for primary immunization — increased the level of antibodies by roughly 37-fold, the company said. A full dose of 100 micrograms was even more powerful,...