{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,13]],"date-time":"2026-10-13T22:59:59Z","timestamp":1791932399250,"version":"4.3.4"},"reference-count":45,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2025,2,28]],"date-time":"2025-02-28T00:00:00Z","timestamp":1740700800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"U.S. Department of Health and Human Services (HHS), Administration for Strategic Preparedness and Response (ASPR), Biomedical Advanced Research and Development Authority (BARDA)","award":["HHSO100201700012C"],"award-info":[{"award-number":["HHSO100201700012C"]}]},{"name":"U.S. Department of Health and Human Services (HHS), Administration for Strategic Preparedness and Response (ASPR), Biomedical Advanced Research and Development Authority (BARDA)","award":["CB10475"],"award-info":[{"award-number":["CB10475"]}]},{"name":"Defense Threat Reduction Agency (DTRA)","award":["HHSO100201700012C"],"award-info":[{"award-number":["HHSO100201700012C"]}]},{"name":"Defense Threat Reduction Agency (DTRA)","award":["CB10475"],"award-info":[{"award-number":["CB10475"]}]},{"name":"Merck Sharp &amp; Dohme LLC","award":["HHSO100201700012C"],"award-info":[{"award-number":["HHSO100201700012C"]}]},{"name":"Merck Sharp &amp; Dohme LLC","award":["CB10475"],"award-info":[{"award-number":["CB10475"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Viruses"],"abstract":"<jats:p>The rVSV\u0394G-ZEBOV-GP vaccine demonstrated efficacy in preventing Ebola virus (EBOV) disease in a ring vaccination clinical trial conducted during the 2014\u20132016 West Africa outbreak and is licensed by regulatory agencies, including the US FDA and the EMA. Here, we present two studies that evaluated the durability of immunogenicity and protection from an EBOV challenge up to ~12 months following vaccination with rVSV\u0394G-ZEBOV-GP in nonhuman primates (NHPs). Cynomolgus macaques were vaccinated with either one or two doses of rVSV\u0394G-ZEBOV-GP or a saline control and were challenged intramuscularly with EBOV at a target dose of 1000 pfu at ~4 months (Study 1) or ~8 or ~12 months (Study 2) after the last vaccination. All vaccinated animals developed robust ZEBOV-GP-specific IgG and neutralizing antibody titers, which were sustained until the last time point tested prior to the challenge. The majority of animals (88\u201393%) challenged with EBOV at ~4 or ~8 months post-vaccination survived, whereas the survival rate was lower (53%) in animals challenged ~12 months post-vaccination. These results demonstrate that both one-dose and two-dose regimens of the rVSV\u0394G-ZEBOV-GP vaccine induced durable ZEBOV-GP-specific antibody titers in NHPs and provided high levels of protection against a lethal EBOV challenge up to ~8 months post-vaccination. In this stringent challenge model, decreased protection was observed at ~12 months post-vaccination despite sustained antibody levels.<\/jats:p>","DOI":"10.3390\/v17030342","type":"journal-article","created":{"date-parts":[[2025,2,28]],"date-time":"2025-02-28T04:28:18Z","timestamp":1740716898000},"page":"342","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Durability of Immunogenicity and Protection of rVSV\u2206G-ZEBOV-GP Vaccine in a Nonhuman Primate EBOV Challenge Model"],"prefix":"10.3390","volume":"17","author":[{"given":"Sandra L.","family":"Bixler","sequence":"first","affiliation":[{"name":"US Army Medical Research Institute of Infectious Diseases, Porter Street, Fort Detrick, MD 21702, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Amy C.","family":"Shurtleff","sequence":"additional","affiliation":[{"name":"US Army Medical Research Institute of Infectious Diseases, Porter Street, Fort Detrick, MD 21702, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Melek M. E.","family":"Sunay","sequence":"additional","affiliation":[{"name":"US Army Medical Research Institute of Infectious Diseases, Porter Street, Fort Detrick, MD 21702, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kenneth","family":"Liu","sequence":"additional","affiliation":[{"name":"Merck & Co., Inc., Lincoln Ave., Rahway, NJ 07065, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ziqiang","family":"Chen","sequence":"additional","affiliation":[{"name":"Merck & Co., Inc., Lincoln Ave., Rahway, NJ 07065, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Michael","family":"Eichberg","sequence":"additional","affiliation":[{"name":"Merck & Co., Inc., Lincoln Ave., Rahway, NJ 07065, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jakub K.","family":"Simon","sequence":"additional","affiliation":[{"name":"Merck & Co., Inc., Lincoln Ave., Rahway, NJ 07065, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Beth-Ann G.","family":"Coller","sequence":"additional","affiliation":[{"name":"Merck & Co., Inc., Lincoln Ave., Rahway, NJ 07065, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sheri","family":"Dubey","sequence":"additional","affiliation":[{"name":"Merck & Co., Inc., Lincoln Ave., Rahway, NJ 07065, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,2,28]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"220","DOI":"10.1007\/s00705-023-05834-2","article-title":"Renaming of genera Ebolavirus and Marburgvirus to Orthoebolavirus and Orthomarburgvirus, respectively, and introduction of binomial species names within family Filoviridae","volume":"168","author":"Biedenkopf","year":"2023","journal-title":"Arch. 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