Efficacy of the AV7909 anthrax vaccine candidate in guinea pigs and nonhuman primates following two immunizations two weeks apart

Vaccine. 2021 Jan 3;39(1):1-5. doi: 10.1016/j.vaccine.2020.10.095. Epub 2020 Nov 13.

Abstract

The anthrax vaccine candidate AV7909 is being developed as a next-generation vaccine for post-exposure prophylaxis (PEP) against inhalational anthrax. In clinical studies, two vaccinations with AV7909 administered either two or four weeks apart induced an enhanced immune response compared to BioThrax® (Anthrax Vaccine Adsorbed) (AVA). Anthrax toxin-neutralizing antibody (TNA) levels on Day 70 following initial vaccination that were associated with protection of animals exposed to inhalational anthrax were previously reported for the 0, 4-week AV7909 vaccination regimen. The current study shows that a 0, 2-week AV7909 vaccination regimen protected guinea pigs (GPs) and nonhuman primates (NHPs) against a lethal inhalational anthrax challenge on Days 28 and 70 after the first immunization. An earlier induction of protective TNA levels using a 0, 2-week AV7909 vaccination regimen may provide benefit over the currently approved AVA PEP 0, 2, and 4-week vaccination regimen.

Keywords: Animal rule; Anthrax vaccine; CPG 7909 adjuvant; Correlates of protection; Cynomolgus macaque; Guinea pig; TNA threshold.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Animals
  • Anthrax Vaccines*
  • Anthrax* / prevention & control
  • Antibodies, Bacterial
  • Antibodies, Neutralizing
  • Antigens, Bacterial
  • Bacillus anthracis*
  • Guinea Pigs
  • Post-Exposure Prophylaxis
  • Primates

Substances

  • Anthrax Vaccines
  • Antibodies, Bacterial
  • Antibodies, Neutralizing
  • Antigens, Bacterial