Nonclinical Safety Profiles of mRNA Therapeutics Comprising Unmodified or N1-Methyl-Pseudouridine-Modified Nucleosides Are Similar Following Repeated Administration

Albena Draycheva, Joske Millecam, Ebru Caba, Regulatory Affairs and Preclinical Safety Department, CureVac Netherlands B, Regulatory Affairs and Preclinical Safety Department, CureVac Belgium SA, Regulatory Affairs and Preclinical Safety Department, CureVac Inc

International Journal of Toxicology

Published online on June 19, 2026

Abstract

International Journal of Toxicology, Ahead of Print.
mRNA, either with unmodified or modified nucleosides, has become an important modality in medicines and vaccines. Despite the inclusion of N1-methyl-pseudouridine (N1mѰ)-modified mRNA in approved coronavirus 2019 (COVID-19) vaccines and the various ...