Observational study: prospective longitudinal cohort (Green)
Interim results from a phase 3 trial of the Moderna mRNA-1273 SARS-CoV-2 vaccine indicated 94% efficacy in preventing COVID-19. The durability of protection is currently unknown. In this article the authors describe mRNA1273-elicited binding and neutralizing antibodies in 33 healthy adult participants in an ongoing phase 1 trial, stratified according to age, at 180 days after the second dose of 100 μg (day 209). Antibody activity remained high in all age groups at day 209. The authors concluded that, although the antibody titers and assays that best correlate with vaccine efficacy are not currently known, antibodies that were elicited by mRNA-1273 persisted through 6 months after the second dose, as detected by three distinct serologic assays. Ongoing studies are monitoring immune responses beyond 6 months as well as determining the effect of a booster dose to extend the duration and breadth of activity against emerging viral variants. Finally, their data show antibody persistence and thus support the use of this vaccine in addressing the COVID-19 pandemic.
Doria-Rose N, et al. Antibody Persistence through 6 Months after the Second Dose of mRNA-1273 Vaccine for COVID-19. N Engl J Med. 2021 Apr 6. doi: 10.1056/NEJMc2103916.
