In Vitro Activity and Resistance Profile of Dasabuvir, a Nonnucleoside Hepatitis C Virus Polymerase Inhibitor
In Vitro Activity and Resistance Profile of Dasabuvir, a Nonnucleoside Hepatitis C Virus Polymerase Inhibitor
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DOI：
10.1128/aac.04619-14
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发表时间：
2015-03-01
影响因子：
4.9
通讯作者：
Collins, Christine
中科院分区：
文献类型：
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作者：
Kati, Warren;Koev, Gennadiy;Collins, Christine
Dasabuvir (ABT-333) 是丙型肝炎病毒 (HCV) NS5B 基因编码的 RNA 依赖性 RNA 聚合酶的非核苷抑制剂。 Dasabuvir 可抑制源自 HCV 基因型 1a 和 1b 临床分离株的重组 NS5B 聚合酶，50% 抑制浓度 (IC50) 值在 2.2 至 10.7 nM 之间，并且对 HCV 基因型 1 聚合酶的抑制选择性至少是人类/哺乳动物聚合酶的 7,000 倍。在HCV亚基因组复制子系统中，达沙布韦抑制基因型1a（菌株H77）和1b（菌株Con1）复制子，50%有效浓度（EC50）值分别为7.7和1.8 nM，在40%人血浆存在下抑制活性降低13倍。针对一组嵌合亚基因组复制子保留了这种活性水平，这些复制子包含来自未接受治疗的患者的 22 个基因型 1 临床分离株的 HCV NS5B 基因，EC(50) 范围在 0.15 至 8.57 nM 之间。将含有复制子的细胞维持在含有浓度比 EC50 高 10 倍或 100 倍的达沙布韦的培养基中，导致选择抗性复制子克隆。对这些克隆的 NS5B 编码区进行测序揭示了变体的存在，包括 C316Y、M414T、Y448C、Y448H 和 S556G，这些变体与与 HCV 聚合酶的 palm I 位点的结合一致。因此，达沙布韦保留了针对已知赋予其他聚合酶抑制剂耐药性的复制子的全部活性，包括核苷结合位点中的 S282T 变体和拇指结构域中的 M423T、P495A、P495S 和 V499A 单一变体。达沙布韦与针对 HCV NS3/NS4A 蛋白酶的抑制剂（ABT-450 与利托那韦）和 NS5A（ombitasvir）联合使用正在开发中，用于治疗 HCV 基因型 1 感染。
Dasabuvir (ABT-333) is a nonnucleoside inhibitor of the RNA-dependent RNA polymerase encoded by the hepatitis C virus (HCV) NS5B gene. Dasabuvir inhibited recombinant NS5B polymerases derived from HCV genotype 1a and 1b clinical isolates, with 50% inhibitory concentration (IC50) values between 2.2 and 10.7 nM, and was at least 7,000-fold selective for the inhibition of HCV genotype 1 polymerases over human/mammalian polymerases. In the HCV subgenomic replicon system, dasabuvir inhibited genotype 1a (strain H77) and 1b (strain Con1) replicons with 50% effective concentration (EC50) values of 7.7 and 1.8 nM, respectively, with a 13-fold decrease in inhibitory activity in the presence of 40% human plasma. This level of activity was retained against a panel of chimeric subgenomic replicons that contained HCV NS5B genes from 22 genotype 1 clinical isolates from treatment-naive patients, with EC(50)s ranging between 0.15 and 8.57 nM. Maintenance of replicon-containing cells in medium containing dasabuvir at concentrations 10-fold or 100-fold greater than the EC50 resulted in selection of resistant replicon clones. Sequencing of the NS5B coding regions from these clones revealed the presence of variants, including C316Y, M414T, Y448C, Y448H, and S556G, that are consistent with binding to the palm I site of HCV polymerase. Consequently, dasabuvir retained full activity against replicons known to confer resistance to other polymerase inhibitors, including the S282T variant in the nucleoside binding site and the M423T, P495A, P495S, and V499A single variants in the thumb domain. The use of dasabuvir in combination with inhibitors targeting HCV NS3/NS4A protease (ABT-450 with ritonavir) and NS5A (ombitasvir) is in development for the treatment of HCV genotype 1 infections.