Retreatment of patients with treatment failure of direct-acting antivirals: Focus on hepatitis C virus genotype 1b

Figure 1 Eradication of hepatitis C virus by interferon and direct-acting antiviral agents against hepatitis C virus. A: Interferon. Interferon induces interferon-stimulated genes (ISGs) transcription after binding its receptors and antiviral proteins. ISGs eradicate hepatitis C virus (HCV) with or without resistance associated substitutions (RASs) although interleukin-28B (IL28B) genotypes have an effect on its treatment results. B: direct-acting antiviral agents (DAAs) easily eradicate HCV without RASs because DAAs work in HCV sequence-specific manner. In some cases, it is difficult for DAAs to eradicate HCV with RASs.