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Copyright ©The Author(s) 2015. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Clin Cases. Mar 16, 2015; 3(3): 210-220
Published online Mar 16, 2015. doi: 10.12998/wjcc.v3.i3.210
Current status and emerging challenges in the treatment of hepatitis C virus genotypes 4 to 6
Vasilios Papastergiou, Stylianos Karatapanis
Vasilios Papastergiou, Stylianos Karatapanis, Department of Internal Medicine, General Hospital of Rhodes, 85100 Rhodes, Greece
Author contributions: Papastergiou V contributed to conception and design, drafting the article; Karatapanis S contributed to revising the intellectual content and gave final approval of the version to be published.
Conflict-of-interest: The authors have nothing to disclose.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Correspondence to: Dr. Vasilios Papastergiou, Department of Internal Medicine, General Hospital of Rhodes, 49 Peiraios Str, 85100 Rhodes, Greece. vasi.pap@hotmail.com
Telephone: +30-22-41027700 Fax: +30-22-41066410
Received: August 29, 2014
Peer-review started: August 29, 2014
First decision: October 14, 2014
Revised: November 1, 2014
Accepted: December 29, 2014
Article in press: December 31, 2014
Published online: March 16, 2015
Processing time: 196 Days and 9.2 Hours
Abstract

Hepatitis C virus (HCV) genotypes 4, 5 and 6 are mainly present in Africa, the Middle East and Asia and they have been less extensively studied with respect to epidemiology, natural disease history and therapeutic endpoints. Response rates to a 48-wk combined peginterferon/ribavirin treatment range to 40%-69% for HCV 4, 55%-60% for HCV 5 and 60%-90% for HCV 6. Response-guided schedules are recommended to optimize the outcomes of peginterferon/ribavirin treatment in HCV 4 and, in form of preliminary data, for HCV 6, but no data are yet available to support such an individualization of therapy for HCV 5. Recently, the direct-acting antivirals (DAAs) with pan-genotypic activities simeprevir, sofosbuvir and daclatasvir have been recommended in triple regimens with peginterferon/ribavirin for the treatment of HCV genotypes 4 to 6 infections. In the future, DAA-based interferon-free therapies are awaited to drastically improve treatment outcomes in HCV. However, efforts to improve treatment outcomes with peginterferon/ribavirin should continue, as the HCV 4-6 infected population is mainly based in resource-limited settings with restricted access to the costly DAAs.

Keywords: Hepatitis C virus; Genotype 4; Genotype 5; Genotype 6; Pegylated interferon; Ribavirin; Direct-acting antivirals

Core tip: Hepatitis C virus (HCV) 4, 5 and 6 are lesser known genotypes mainly encountered in Africa, the Middle East and Asia. Studies, mostly retrospective, have reported response rates to a 48-wk peginterferon/ribavirin combination ranging to 40%-69% for HCV-4, 55%-60% for HCV-5 and 60%-90% for HCV-6. Increasing evidence has supported a response-guided approach for HCV-4, whereas no robust data are yet available concerning tailoring of treatment duration for HCV-5 and HCV-6. Direct-acting antivirals may significantly improve treatment outcomes in HCV, but use of these agents in countries endemic for HCV 4-6 is currently precluded by the very high costs.