mRNA-1011.2

mRNA-1011.2 is an investigational next-generation seasonal influenza vaccine candidate developed by Moderna. It is a quadrivalent mRNA-based vaccine that encodes the hemagglutinin (HA) surface glycoproteins of three influenza strains recommended by the World Health Organization for the 2022/2023 Northern Hemisphere season—A/H1N1, A/H3N2, and B/Victoria lineage—as well as one alternative A/H3N2 strain (A/Newcastle/1/2021) replacing B/Yamagata[2][3]. The vaccine uses lipid nanoparticle (LNP) technology to deliver four distinct mRNAs encoding these antigens[4]. Preclinical studies in mice and ferrets demonstrated robust immunogenicity against all encoded HA antigens, with no evidence of synergistic or additive toxicity between components[4]. Clinical trials have shown that mRNA-1011.2 elicits strong immune responses against all targeted strains at Day 29 post-vaccination, comparable to or exceeding those induced by current quadrivalent controls[3]. The primary indication under investigation is prevention of seasonal influenza.