Limited Benefit of Postexposure Prophylaxis With VSV-EBOV in Ebola Virus-Infected Rhesus Macaques.

Vesicular stomatitis virus-Ebola virus (VSV-EBOV) vaccine has been successfully used in ring vaccination approaches during EBOV disease outbreaks demonstrating its general benefit in short-term prophylactic vaccination, but actual proof of its benefit in true postexposure prophylaxis (PEP) for humans is missing. Animal studies have indicated PEP efficacy when VSV-EBOV was used within hours of lethal EBOV challenge. Here, we used a lower EBOV challenge dose and a combined intravenous and intramuscular VSV-EBOV administration to improve PEP efficacy in the rhesus macaque model. VSV-EBOV treatment 1 hour after EBOV challenge resulted in delayed disease progression but little benefit in outcome. Thus, we could not confirm previous results indicating questionable benefit of VSV-EBOV for EBOV PEP in a nonhuman primate model.
Competing Interests: Potential conflicts of interest. H. F. and T. W. G. claim intellectual property for vesicular stomatitis virus–based filovirus vaccines. All other authors report no potential conflicts. All authors have submitted the ICMJE Form for Disclosure of Potential Conflicts of Interest. Conflicts that the editors consider relevant to the content of the manuscript have been disclosed.
(Published by Oxford University Press on behalf of Infectious Diseases Society of America 2023.)