title: Efficacy of the antipoxvirus compound ST-246 for treatment of severe orthopoxvirus infection.
abstract: Efficacy of the new antipoxvirus compound ST-246 was evaluated as treatment of monkeypox (MPX) virus infection in a ground squirrel model of the disease. Ground squirrels were given a lethal dose of MPX virus and were then treated orally at various times post-inoculation (pi) with 100 mg/kg/day of ST-246. Morbidity and mortality, clinical laboratory results, viral load, and pathology of placebo and treatment groups were compared. All animals that started treatment with ST-246 on days 0, 1, 2, and 3 pi survived lethal challenge with MPX virus; 67% of animals treated on day 4 pi also survived. In contrast, 100% of the placebo group died. Most of the ST-246-treated animals showed no evidence of clinical disease or alteration of baseline clinical laboratory values and had minimal histopathologic changes. These results suggest that ST-246 is a promising candidate for early treatment of severe orthopoxvirus infection.
authors.affiliation: Department of Pathology and Internal Medicine, University of Texas Medical Branch, Galveston, Texas 77555, USA.
authors.forename: Elena
authors.initials: E
authors.lastname: Sbrana
authors.forename: Robert
authors.initials: R
authors.lastname: Jordan
authors.forename: Dennis E
authors.initials: DE
authors.lastname: Hruby
authors.forename: Rosa I
authors.initials: RI
authors.lastname: Mateo
authors.forename: Shu-Yuan
authors.initials: SY
authors.lastname: Xiao
authors.forename: Marina
authors.initials: M
authors.lastname: Siirin
authors.forename: Patrick C
authors.initials: PC
authors.lastname: Newman
authors.forename: Amelia P A Travassos
authors.initials: AP
authors.lastname: DA Rosa
authors.forename: Robert B
authors.initials: RB
authors.lastname: Tesh
mesh_terms: D000820:Animal Diseases / Q000188:drug therapy* / Q000821:virology*; D000818:Animals; D000998:Antiviral Agents / Q000493:pharmacokinetics / Q000627:therapeutic use*; D001549:Benzamides / Q000493:pharmacokinetics / Q000627:therapeutic use*; D004334:Drug Administration Schedule; D007211:Indoles / Q000493:pharmacokinetics / Q000627:therapeutic use*; D054833:Isoindoles; D008099:Liver / Q000473:pathology; D008168:Lung / Q000473:pathology; D023421:Models, Animal; D045908:Mpox, Monkeypox / Q000188:drug therapy / Q000401:mortality / Q000662:veterinary* / Q000821:virology; D012589:Sciuridae / Q000821:virology*; D013154:Spleen / Q000473:pathology; D013997:Time Factors; D010797:Phthalimides
chemical_list: D000998:Antiviral Agents; D001549:Benzamides; D007211:Indoles; D054833:Isoindoles; C505045:tecovirimat; D010797:Phthalimides