title: Nonnucleoside inhibitor of measles virus RNA-dependent RNA polymerase complex activity.
abstract: Paramyxoviruses comprise several major human pathogens. Although a live-attenuated vaccine protects against measles virus (MV), a member of the paramyxovirus family, the virus remains a principal cause of worldwide mortality and accounts for approximately 21 million cases and 300,000 to 400,000 deaths annually. The development of novel antivirals that allow improved case management of severe measles and silence viral outbreaks is thus highly desirable. We have previously described the development of novel MV fusion inhibitors. The potential for preexisting or emerging resistance in the field constitutes the rationale for the identification of additional MV inhibitors with a diverse target spectrum. Here, we report the development and implementation of a cell-based assay for high-throughput screening of MV antivirals, which has yielded several hit candidates. Following confirmation by secondary assays and chemical synthesis, the most potent hit was found to act as a target-specific inhibitor of MV replication with desirable drug-like properties. The compound proved highly active against multiple primary isolates of diverse MV genotypes currently circulating worldwide, showing active concentrations of 35 to 145 nM. Significantly, it does not interfere with viral entry and lacks cross-resistance with the MV fusion inhibitor class. Mechanistic characterization on a subinfection level revealed that the compound represents a first-in-class nonnucleoside inhibitor of MV RNA-dependent RNA polymerase complex activity. Singly or in combination with the fusion inhibitors, this novel compound class has high developmental potential as a potent therapeutic against MV and will likely further the mechanistic characterization of the viral polymerase complex.
authors.affiliation: Division of Infectious Diseases, Emory University School of Medicine, Atlanta, GA 30322, USA.
authors.forename: Laura K
authors.initials: LK
authors.lastname: White
authors.forename: Jeong-Joong
authors.initials: JJ
authors.lastname: Yoon
authors.forename: Jin K
authors.initials: JK
authors.lastname: Lee
authors.forename: Aiming
authors.initials: A
authors.lastname: Sun
authors.forename: Yuhong
authors.initials: Y
authors.lastname: Du
authors.forename: Haian
authors.initials: H
authors.lastname: Fu
authors.forename: James P
authors.initials: JP
authors.lastname: Snyder
authors.forename: Richard K
authors.initials: RK
authors.lastname: Plemper
mesh_terms: D000818:Animals; D000998:Antiviral Agents / Q000138:chemical synthesis / Q000737:chemistry / Q000378:metabolism* / Q000494:pharmacology*; D002459:Cell Fusion; D002460:Cell Line; D002522:Chlorocebus aethiops; D004285:Dogs; D004305:Dose-Response Relationship, Drug; D015195:Drug Design; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D004795:Enzyme Stability; D020128:Inhibitory Concentration 50; D008459:Measles virus / Q000187:drug effects* / Q000201:enzymology*; D015394:Molecular Structure; D012367:RNA, Viral / Q000096:biosynthesis / Q000235:genetics; D012324:RNA-Dependent RNA Polymerase / Q000378:metabolism*; D013329:Structure-Activity Relationship; D014162:Transfection; D014709:Vero Cells
chemical_list: D000998:Antiviral Agents; D004791:Enzyme Inhibitors; D012367:RNA, Viral; D012324:RNA-Dependent RNA Polymerase