Identification of novel anti-hepatitis C virus agents by a quantitative high throughput screen in a cell-based infection assay

Abstract

Hepatitis C virus (HCV) poses a major health threat to the world. The recent development of direct-acting antivirals (DAAs) against HCV has markedly improved the response rate of HCV and reduced the side effects in comparison to the interferon-based therapy. Despite this therapeutic advance, there is still a need to develop new inhibitors that target different stages of the HCV life cycle because of various limitations of the current regimens. In this study, we performed a quantitative high-throughput screening of the Molecular Libraries Small Molecule Repository (MLSMR) of ~ 350,000 chemicals for novel HCV inhibitors using our previously developed cell-based HCV infection assay. Following confirmation and structural clustering analysis, we narrowed down to 158 compounds from the initial ~ 3,000 molecules that showed inhibitory activity for further structural and functional analyses. We were able to assign the majority of these compounds to specific stage(s) in the HCV life cycle. Three of them are direct inhibitors of NS3/4A protease. Most of the compounds appear to act on novel targets in HCV life cycle. Four compounds with novel structure and excellent drug-like properties, three targeting HCV entry and one targeting HCV assembly/secretion, were advanced for further development as lead hits. These compounds represent diverse chemotypes that are potential lead compounds for further optimization and may offer promising candidates for the development of novel therapeutics against HCV infection. In addition, they represent novel molecular probes to explore the complex interactions between HCV and the cells.

Preclinical Pharmacological Development of Chlorcyclizine Derivatives for the Treatment of Hepatitis C Virus Infection

“…Therapeutic regimens are not chosen solely based on patient needs but are determined by what resources are available from the point of view of the health care provider. Advancements in HCV cell culture systems allowed us to approach this problem from a phenotypic perspective, to develop treatments that have a different mode of action from the existing DAAs, and are thus likely synergistic with currently available drugs due to their mechanism of action [21][22][23]. We have previously shown that CCZ inhibits the entry step of HCV infection and exhibits synergistic activity with currently approved anti-HCV agents in vitro [14,24].…”

Identification of Piperazinylbenzenesulfonamides as New Inhibitors of Claudin-1 Trafficking and Hepatitis C Virus Entry

“…Several compounds targeting other GPCRs were identified as HCV inhibitors in our screen. Previous studies described antihistamines, neuroleptic drugs, and other ligands of GPCRs as inhibitors of HCV entry (16,43,44). In the future, it would be interesting to test if the viral resistance mutations against any of these drugs eventually confer cross-resistance to piperazinylbenzenesulfonamides.…”

Discovery and Characterization of a Novel HCV Inhibitor Targeting the Late Stage of HCV Life Cycle

“…Recently, our laboratory identified multiple candidate compounds as late-stage HCV inhibitors via high-throughput screen [12]. In the current study, we validated and characterized MLS000833705, a late-stage HCV inhibitor, as a molecular probe for viral assembly and potential candidate for therapeutic development.…”