{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,16]],"date-time":"2026-06-16T17:57:23Z","timestamp":1781632643095,"version":"3.54.5"},"reference-count":30,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2023,1,26]],"date-time":"2023-01-26T00:00:00Z","timestamp":1674691200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Tonix Pharmaceuticals"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Viruses"],"abstract":"<jats:p>The ongoing global Monkeypox outbreak that started in the spring of 2022 has reinforced the importance of protecting the population using live virus vaccines based on the vaccinia virus (VACV). Smallpox also remains a biothreat and although some U.S. military personnel are immunized with VACV, safety concerns limit its use in other vulnerable groups. Consequently, there is a need for an effective and safer, single dose, live replicating vaccine against both viruses. One potential approach is to use the horsepox virus (HPXV) as a vaccine. Contemporary VACV shares a common ancestor with HPXV, which from the time of Edward Jenner and through the 19th century, was extensively used to vaccinate against smallpox. However, it is unknown if early HPXV-based vaccines exhibited different safety and efficacy profiles compared to modern VACV. A deeper understanding of HPXV as a vaccine platform may allow the construction of safer and more effective vaccines against the poxvirus family. In a proof-of-concept study, we vaccinated cynomolgus macaques with TNX-801, a recombinant chimeric horsepox virus (rcHPXV), and showed that the vaccine elicited protective immune responses against a lethal challenge with monkeypox virus (MPXV), strain Zaire. The vaccine was well tolerated and protected animals from the development of lesions and severe disease. These encouraging data support the further development of TNX-801.<\/jats:p>","DOI":"10.3390\/v15020356","type":"journal-article","created":{"date-parts":[[2023,1,27]],"date-time":"2023-01-27T01:58:59Z","timestamp":1674784739000},"page":"356","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":17,"title":["Single Dose of Recombinant Chimeric Horsepox Virus (TNX-801) Vaccination Protects Macaques from Lethal Monkeypox Challenge"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-9463-7314","authenticated-orcid":false,"given":"Ryan S.","family":"Noyce","sequence":"first","affiliation":[{"name":"Department of Medical Microbiology & Immunology, Li Ka Shing Institute of Virology, University of Alberta, Edmonton, AB T6G 2R3, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Landon W.","family":"Westfall","sequence":"additional","affiliation":[{"name":"Southern Research, Birmingham, AL 35205, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Siobhan","family":"Fogarty","sequence":"additional","affiliation":[{"name":"Tonix Pharmaceuticals, Dartmouth, MA 02748, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Karen","family":"Gilbert","sequence":"additional","affiliation":[{"name":"Southern Research, Birmingham, AL 35205, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Onesmo","family":"Mpanju","sequence":"additional","affiliation":[{"name":"LINQ Pharma Consulting Inc., Aldie, VA 20105, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Helen","family":"Stillwell","sequence":"additional","affiliation":[{"name":"Tonix Pharmaceuticals, Dartmouth, MA 02748, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2305-6264","authenticated-orcid":false,"given":"Jos\u00e9","family":"Esparza","sequence":"additional","affiliation":[{"name":"Institute of Human Virology, University of Maryland School of Medicine, Baltimore, MD 21201, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Bruce","family":"Daugherty","sequence":"additional","affiliation":[{"name":"Tonix Pharmaceuticals, Dartmouth, MA 02748, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Fusataka","family":"Koide","sequence":"additional","affiliation":[{"name":"Southern Research, Birmingham, AL 35205, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5871-299X","authenticated-orcid":false,"given":"David H.","family":"Evans","sequence":"additional","affiliation":[{"name":"Department of Medical Microbiology & Immunology, Li Ka Shing Institute of Virology, University of Alberta, Edmonton, AB T6G 2R3, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2781-1455","authenticated-orcid":false,"given":"Seth","family":"Lederman","sequence":"additional","affiliation":[{"name":"Tonix Pharmaceuticals, Dartmouth, MA 02748, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,1,26]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"841","DOI":"10.5694\/j.1326-5377.1984.tb132965.x","article-title":"Smallpox, \u201cthe most dreadful scourge of the human species.\u201d Its global spread and recent eradication","volume":"141","author":"Fenner","year":"1984","journal-title":"Med. 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