Copyright ©The Author(s) 2016. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Jul 7, 2016; 22(25): 5623-5626
Published online Jul 7, 2016. doi: 10.3748/wjg.v22.i25.5623
Symbiotic chemo- and immuno-therapy for hepatitis B and C viruses
Babita Agrawal, Rakesh Kumar
Babita Agrawal, Department of Surgery, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB T6G 2R3, Canada
Rakesh Kumar, Department of Laboratory Medicine and Pathology, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB T6G 2R3, Canada
Author contributions: Agrawal B and Kumar R wrote the manuscript.
Conflict-of-interest statement: Agrawal B and Kumar R have no conflict of interest to declare.
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. Rakesh Kumar, Professor, Department of Laboratory Medicine and Pathology, Faculty of Medicine and Dentistry, University of Alberta, 116 St and 85 Ave, Edmonton, AB T6G 2R3, Canada. rkumar@ualberta.ca
Telephone: +1-780-4927545
Received: May 4, 2016
Peer-review started: May 4, 2016
First decision: May 27, 2016
Revised: May 31, 2016
Accepted: June 13, 2016
Article in press: June 13, 2016
Published online: July 7, 2016

Hepatitis B and C viruses (HBV and HCV), both cause serious chronic infections leading to fatal liver diseases. The prototype therapy for both HBV and HCV was based on IFN-α with or without ribavirin. The advent of direct-acting antivirals (DAA) for both HBV and HCV has remarkably improved the standard of treatment for both infections. While HCV can be eliminated following combination DAA therapy, HBV persists even after treatment, requiring life-long therapy with DAAs. Treatment with DAAs is also associated with high cost, the development of resistance and side effects. There is ample published evidence that both HBV and HCV can be eliminated from infected host cells through non-cytolytic immune mechanisms. We need to identify the mechanisms behind this successful elimination of replicating viruses and develop them into novel immunotherapeutic regimens. Moreover, a synergy of, chemo- and immuno-therapeutic strategies will be necessary to eradicate HBV or HCV from a host.

Keywords: Hepatitis C virus, Hepatitis B virus, Direct-acting antiviral, Chemotherapy, Immunotherapy

Core tip: Immune related mechanisms have been shown to eliminate both Hepatitis B and C viruses (HBV and HCV) from chronically infected host cells via non-cytolytic mechanisms. Current direct-acting antivirals against replication of both HBV and HCV are effective and provide significant viral suppression in a relatively short period of time. This time window should be harnessed to target host-mediated immune mechanisms to clear the host of the infection. This strategy would lead to a significant reduction in cost, duration, side effects and development of resistance associated with direct-acting antivirals therapy. In summary, regimens combining chemo- and immuno-therapy must be used in a mutually beneficial manner to eradicate HBV and/or HCV from a host.