Moderna says updated Covid-19 vaccine booster shows stronger antibody response against Omicron

(CNN) Moderna said on Wednesday its bivalent Covid-19 vaccine booster that contained a vaccine targeting the Omicron variant showed a stronger immune response against the variant.

Bivalent boosters address two viral strains in the same vaccine. The updated booster contains Moderna's original vaccine, and a vaccine candidate that targets the Omicron variant.

The vaccine was generally well-tolerated, the company said, with side effects similar to booster doses of the current vaccine.

The 50-microgram bivalent booster, called mRNA-1273.214, generated a stronger antibody response against Omicron than the original Moderna vaccine. Omicron subvariants are driving virtually all the new Covid-19 cases in the United States right now.

Stéphane Bancel, chief executive officer of Moderna, said in a news release "we anticipate more durable protection against variants of concern with mRNA-1273.214, making it our lead candidate for a Fall 2022 booster."