Steensels D, Pierlet N, Penders J, et al. - The SARS-CoV-2 mRNA-1273 vaccine (Moderna) was identified to induce a significantly higher humoral immunogenicity when compared with the BNT162b2 vaccine (Pfizer-BioNTech), in infected as well as uninfected participants, and across age categories. This difference is possibly due to the higher mRNA content in mRNA-1273 compared with BNT162b2 and the longer interval between priming and boosting for mRNA-1273 (4 weeks vs 3 weeks for BNT162b2).

• In this cohort study, participants were 1,647 health care workers who were scheduled for vaccination with 2 doses of either mRNA-1273 or BNT162b2.

• Participants vaccinated with 2 doses of mRNA-1273 showed higher antibody titers when compared with those vaccinated with BNT162b2 (geometric mean titer [GMT], 3836 U/mL vs 1444 U/mL).

• Higher antibody titers were recorded in previously infected participants vs uninfected participants (GMT, 9461 U/mL vs 1613 U/mL).

• In previously uninfected participants, a negative correlation appeared between antibody levels and age.