A phase 3 randomized safety and immunogenicity trial of mRNA-1010 seasonal influenza vaccine in adults

Abstract

Messenger RNA (mRNA)-based influenza vaccines have the potential to improve upon limitations of current vaccine approaches to seasonal influenza. Here we report findings on the primary and secondary objectives of the safety, reactogenicity, and humoral immunogenicity of the quadrivalent mRNA vaccine, mRNA-1010, versus licensed standard-dose and high-dose quadrivalent influenza vaccines from a three-part, phase 3 clinical trial in adults aged ≥18 years (Part A), 18–64 years (Part B), and ≥ 65 years (Part C) ( NCT05827978 ). A single 50-μg dose of mRNA-1010 elicited hemagglutination inhibition titers against vaccine-matched strains that were statistically noninferior and superior to licensed standard-dose and high-dose egg-based quadrivalent vaccine comparators. Solicited adverse reactions were more frequent with receipt of mRNA-1010; adverse reactions were lower in frequency and severity among adults aged ≥65 years than younger adults. No safety concerns were identified. These findings support the potential benefit of mRNA-1010 as a seasonal influenza vaccine. • Seasonal influenza viral infections are a global health concern. • mRNA platform may improve upon limitations of current influenza vaccine technology. • mRNA-1010 is an mRNA-based vaccine targeting seasonal influenza A and B strains. • mRNA-1010 elicited strong immune responses in adults of all ages. • No safety concerns were identified with mRNA-1010 in this phase 3 study.