Moderna Inc.’s booster shot of its bivalent vaccine sharply increased antibody levels against recent COVID-19 strains when compared to a fourth dose of its original immunization.
People given the bivalent vaccine, mRNA-1273.222, as their fourth shot generated levels of protective antibodies against the BA.4 and BA.5 strains that were five-fold to six-fold higher than those seen in adults given a repeat dose of the original, the Cambridge, Massachusetts-based company said in a statement. Antibody levels were measured after 28 days in the trial involving more than 500 people, a company spokesperson said.
The Moderna finding is roughly line with a smaller study from rival vaccine maker Pfizer Inc. and its German partner BioNTech SE. In that study, antibody levels to BA.4 and BA.5 variants were four-fold higher in people over 55 who received the bivalent shot compared to those who received a fourth shot of the original vaccine.
