title: Discovery of Dengue Virus NS4B Inhibitors.
abstract: The four serotypes of dengue virus (DENV-1 to -4) represent the most prevalent mosquito-borne viral pathogens in humans. No clinically approved vaccine or antiviral is currently available for DENV. Here we report a spiropyrazolopyridone compound that potently inhibits DENV both in vitro and in vivo. The inhibitor was identified through screening of a 1.8-million-compound library by using a DENV-2 replicon assay. The compound selectively inhibits DENV-2 and -3 (50% effective concentration [EC50], 10 to 80 nM) but not DENV-1 and -4 (EC50,>20 M). Resistance analysis showed that a mutation at amino acid 63 of DENV-2 NS4B (a nonenzymatic transmembrane protein and a component of the viral replication complex) could confer resistance to compound inhibition. Genetic studies demonstrate that variations at amino acid 63 of viral NS4B are responsible for the selective inhibition of DENV-2 and -3. Medicinal chemistry improved the physicochemical properties of the initial “hit” (compound 1), leading to compound 14a, which has good in vivo pharmacokinetics. Treatment of DENV-2-infected AG129 mice with compound 14a suppressed viremia, even when the treatment started after viral infection. The results have proven the concept that inhibitors of NS4B could potentially be developed for clinical treatment of DENV infection. Compound 14a represents a potential preclinical candidate for treatment of DENV-2- and -3-infected patients.
authors.forename: Qing-Yin
authors.initials: QY
authors.lastname: Wang
authors.forename: Hongping
authors.initials: H
authors.lastname: Dong
authors.forename: Bin
authors.initials: B
authors.lastname: Zou
authors.forename: Ratna
authors.initials: R
authors.lastname: Karuna
authors.forename: Kah Fei
authors.initials: KF
authors.lastname: Wan
authors.forename: Jing
authors.initials: J
authors.lastname: Zou
authors.forename: Agatha
authors.initials: A
authors.lastname: Susila
authors.forename: Andy
authors.initials: A
authors.lastname: Yip
authors.forename: Chao
authors.initials: C
authors.lastname: Shan
authors.forename: Kim Long
authors.initials: KL
authors.lastname: Yeo
authors.forename: Haoying
authors.initials: H
authors.lastname: Xu
authors.forename: Mei
authors.initials: M
authors.lastname: Ding
authors.forename: Wai Ling
authors.initials: WL
authors.lastname: Chan
authors.forename: Feng
authors.initials: F
authors.lastname: Gu
authors.forename: Peck Gee
authors.initials: PG
authors.lastname: Seah
authors.forename: Wei
authors.initials: W
authors.lastname: Liu
authors.forename: Suresh B
authors.initials: SB
authors.lastname: Lakshminarayana
authors.forename: CongBao
authors.initials: C
authors.lastname: Kang
authors.forename: Julien
authors.initials: J
authors.lastname: Lescar
authors.forename: Francesca
authors.initials: F
authors.lastname: Blasco
authors.forename: Paul W
authors.initials: PW
authors.lastname: Smith
authors.forename: Pei-Yong
authors.initials: PY
authors.lastname: Shi
mesh_terms: D000818:Animals; D000998:Antiviral Agents / Q000494:pharmacology*; D002460:Cell Line; D006224:Cricetinae; D003716:Dengue Virus / Q000187:drug effects*; D055808:Drug Discovery; D006801:Humans; D013141:Spiro Compounds / Q000737:chemistry / Q000494:pharmacology*; D017361:Viral Nonstructural Proteins / Q000037:antagonists & inhibitors*
chemical_list: D000998:Antiviral Agents; C080107:NS4B protein, flavivirus; D013141:Spiro Compounds; D017361:Viral Nonstructural Proteins; C088106:spiroquinazoline