Korean J Gastroenterol.  2015 Jul;66(1):5-9. 10.4166/kjg.2015.66.1.5.

New Therapeutic Agent for Chronic Hepatitis C: Direct Acting Agent

• Chae HB

• KMID: 2373305
• DOI: http://doi.org/10.4166/kjg.2015.66.1.5

Abstract

Peg-interferon and ribavirin has been the standard therapy of chronic hepatitis C for the past 15 years in Korea. However, the treatment paradigm is changing. Direct acting agents (DAAs) are oral pills that can be easily taken. In addition, DAAs are more effective and have less adverse reactions compared to the previously used drugs. Chronic hepatitis C is hard to treat because the virus is error-prone virus. Host immunity is helpless against the hepatitis C virus since it evades the host immunity through various complex mechanisms. There are 6 genotypes. Quasispecies can co-exist even in the same patients. The treatment strategy is based on the combination of the individual drug corresponding to each step of viral replication process. NS5B nucleosides are the most powerful and effective drug available until now. Other drugs with different mechanisms of action can be used to provide synergy. NS5A and NS5B inhibition drugs currently belong to the leading group amongst many DAAs. These drugs will soon be available in Korea. We have to know the merits and adverse drug reactions of the new drug.

Keyword

Hepatitis C, chronic; Therapeutics

MeSH Terms

Antiviral Agents/*therapeutic use
Drug Therapy, Combination
Enzyme Inhibitors/therapeutic use
Genotype
Guidelines as Topic
Hepacivirus/genetics
Hepatitis C, Chronic/*drug therapy/immunology/virology
Humans
Viral Nonstructural Proteins/antagonists & inhibitors/metabolism
Antiviral Agents
Enzyme Inhibitors
Viral Nonstructural Proteins

Figure

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  Fig. 1. Direct acting agents and corresponding sites of HCV gene. Modified from the article of Chae et al.12 (ScientificWorldJournal 2013. doi: 10.1155/2013/704912).

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  Fig. 2. Targets for direct acting agent. Adapted from the article of Racanelli and Rehermann13 (Trends Immunol 2003;24:456–464) with the permission of original copyright holder. LDL, low density lipoprotein; VLDL, very low density lipoprotein; ER, endoplasmic reticulum; NS3/4A, protease; NS5A, replication complex; NS5B, RNA dependent RNA polymerase.

Reference

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