N Engl J Med reported the durability of immunity response of SARS-CoV-2 vaccine, mRNA-1273 (Moderna). The data was from 34 healthy adults with two vaccine injections. They have performed RBD binding assay and antibody neutralization assay, which revealed that there was no significant change in both RBD binding ability and neutralized inhibitory effect of antibodies over time. The results suggest that the effect of vaccination can last at least 4 months. (Widge et al., 2021)

Binding to spike receptor–binding domain (RBD) protein (the end-point dilution titer) assessed on enzyme-linked immunosorbent assay (ELISA) on days 1, 15, 29, 36, 43, 57, and 119.

The 50% inhibitory dilution (ID50) titer on pseudovirus neutralization assay on days 1, 15, 29, 36, 43, 57, and 119.

Figures. Time Course of SARS-CoV-2 Antibody Binding and Neutralization Responses after mRNA-1273 Vaccination (Widge et al., 2021)