Self-amplifying RNA SARS-CoV-2 lipid nanoparticle vaccine candidate induces high neutralizing antibody titers in mice

The spread of the SARS-CoV-2 into a global pandemic within a few months of onset motivates the development of a rapidly scalable vaccine. Here, we present a self-amplifying RNA encoding the SARS-CoV-2 spike protein encapsulated within a lipid nanoparticle (LNP) as a vaccine. We observe remarkably high and dose-dependent SARS-CoV-2 specific antibody titers in mouse sera, as well as robust neutralization of both a pseudo-virus and wild-type virus. Upon further characterization we find that the neutralization is proportional to the quantity of specific IgG and of higher magnitude than recovered COVID-19 patients. saRNA LNP immunizations induce a Th1-biased response in mice, and there is no antibody-dependent…

• NI
  National Institute for Health and Care Research
• DO
  Department of Health and Social Care

  Award: EP/R013764/1
• IC
  Imperial College London

  Award: H2020
• IC
  Imperial College Healthcare NHS Trust
• EC
  European Commission

  Awards: 794059, H2020, COVID-19
• UO
  University of Bristol
• H2
  Horizon 2020 Framework Programme

  Award: 794059
• EA
  Engineering and Physical Sciences Research Council

  Awards: EP/R013764/1, H2020, EP/R013764/1