title: HCV antiviral resistance: the impact of in vitro studies on the development of antiviral agents targeting the viral NS5B polymerase.
abstract: The high prevalence of the disease caused by hepatitis C virus (HCV) and the limited efficacy of interferon-based therapies have stimulated the search for safer and more effective drugs. The development of inhibitors of the HCV NS5B RNA polymerase represents a promising strategy for identifying novel anti-HCV therapeutics. However, the high genetic diversity, mutation rate and turnover of HCV are expected to favour the emergence of drug resistance, limiting the clinical usefulness of polymerase inhibitors. Thus, the characterization of the drug-resistance profile of these antiviral agents is considered crucial for identifying the inhibitors with a higher probability of clinical success. In the absence of an efficient in vitro infection system, HCV sub-genomic replicons have been used to study viral resistance to both nucleoside and non-nucleoside NS5B inhibitors. While these studies suggest that drug-resistant viruses are likely to evolve in vivo, they provide a wealth of information that should help in the identification of inhibitors with improved and distinct resistance profiles that might be used for combination therapy.
authors.affiliation: Istituto di Ricerche di Biologia Molecolare P Angeletti, Pomezia-Roma, Italy.
authors.forename: Licia
authors.initials: L
authors.lastname: Tomei
authors.forename: Sergio
authors.initials: S
authors.lastname: Altamura
authors.forename: Giacomo
authors.initials: G
authors.lastname: Paonessa
authors.forename: Raffaele
authors.initials: R
authors.lastname: De Francesco
authors.forename: Giovanni
authors.initials: G
authors.lastname: Migliaccio
mesh_terms: D000818:Animals; D000998:Antiviral Agents / Q000737:chemistry / Q000494:pharmacology*; D024882:Drug Resistance, Viral; D016679:Genome, Viral; D016174:Hepacivirus / Q000187:drug effects* / Q000235:genetics; D006801:Humans; D015394:Molecular Structure; D009154:Mutation; D012324:RNA-Dependent RNA Polymerase / Q000037:antagonists & inhibitors* / Q000737:chemistry; D017361:Viral Nonstructural Proteins / Q000037:antagonists & inhibitors* / Q000737:chemistry
chemical_list: D000998:Antiviral Agents; D017361:Viral Nonstructural Proteins; C087036:NS-5 protein, hepatitis C virus; D012324:RNA-Dependent RNA Polymerase