Amparo L. Figueroa, Bethany Girard, Darin K. Edwards, Arshan Nasir, Kimball Johnson, Steven Hack, Xin Cao, Elizabeth de Windt, Verónica Urdaneta, Frances Priddy, Rituparna Das, David C. Montefiori, Spyros Chalkias
In this ongoing, open-label, phase 3b/4 study, JN.1- and KP.2-encoding monovalent mRNA-1273 vaccines elicited robust neutralization of vaccine-matched variants (JN.1, KP.2) and cross-neutralized JN.1 subvariants circulating during the study (September 2024-November 2024; KP.3.1.1, XEC, LP.8.1) in vaccinated adults, showing reduced cross-neutralization against all subvariants tested. No safety concerns were identified.