Preclinical and Clinical Demonstration of Immunogenicity by mRNA Vaccines against H10N8 and H7N9 Influenza Viruses

Mol Ther. 2017 Jun 7;25(6):1316-1327. doi: 10.1016/j.ymthe.2017.03.035. Epub 2017 Apr 27.


Recently, the World Health Organization confirmed 120 new human cases of avian H7N9 influenza in China resulting in 37 deaths, highlighting the concern for a potential pandemic and the need for an effective, safe, and high-speed vaccine production platform. Production speed and scale of mRNA-based vaccines make them ideally suited to impede potential pandemic threats. Here we show that lipid nanoparticle (LNP)-formulated, modified mRNA vaccines, encoding hemagglutinin (HA) proteins of H10N8 (A/Jiangxi-Donghu/346/2013) or H7N9 (A/Anhui/1/2013), generated rapid and robust immune responses in mice, ferrets, and nonhuman primates, as measured by hemagglutination inhibition (HAI) and microneutralization (MN) assays. A single dose of H7N9 mRNA protected mice from a lethal challenge and reduced lung viral titers in ferrets. Interim results from a first-in-human, escalating-dose, phase 1 H10N8 study show very high seroconversion rates, demonstrating robust prophylactic immunity in humans. Adverse events (AEs) were mild or moderate with only a few severe and no serious events. These data show that LNP-formulated, modified mRNA vaccines can induce protective immunogenicity with acceptable tolerability profiles.

Keywords: H10N8; H7N9; immunogenicity; influenza; mRNA; mRNA vaccines; pandemic; vaccines.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antibodies, Viral / blood
  • Antibodies, Viral / immunology
  • Cell Line
  • Disease Models, Animal
  • Female
  • Ferrets
  • Gene Expression
  • Humans
  • Immunization
  • Immunization Schedule
  • Influenza A Virus, H10N8 Subtype / genetics*
  • Influenza A Virus, H10N8 Subtype / immunology*
  • Influenza A Virus, H7N9 Subtype / genetics*
  • Influenza A Virus, H7N9 Subtype / immunology*
  • Influenza Vaccines / administration & dosage
  • Influenza Vaccines / adverse effects
  • Influenza Vaccines / immunology*
  • Macaca fascicularis
  • Male
  • Mice
  • Orthomyxoviridae Infections / prevention & control*
  • Protamines
  • RNA, Messenger / administration & dosage
  • RNA, Messenger / genetics*
  • RNA, Messenger / pharmacokinetics
  • RNA, Viral
  • Tissue Distribution


  • Antibodies, Viral
  • Influenza Vaccines
  • Protamines
  • RNA, Messenger
  • RNA, Viral