Biological basis for functional cure of chronic hepatitis B

J Viral Hepat. 2019 Jul;26(7):786-794. doi: 10.1111/jvh.13090. Epub 2019 Mar 29.

Abstract

Chronic hepatitis B (CHB) infection affects over 250 millon people worldwide and 800000 are expected to die yearly due to the development of hepatocellular carcinoma (HCC). Current antiviral therapies include nucleoside analogs (NAs) that target the viral retrotranscriptase inhibiting de novo viral production. Pegylated interferon (Peg-IFN) is also effective in reducing the viral DNA load in serum. However, both treatments remain limited to control the infection, aiming for viral suppression and improving the quality of life of the infected patients. Complete cure is not possible due to the presence of the stable DNA intermediate covalently closed circular DNA (cccDNA). Attempts to achieve a functional cure are thus ongoing and novel targets and molecules, together with different combination therapies are currently in the pipeline for early clinical trials. In this review we discuss novel treatments both targeting directly and indirectly cccDNA. As we gain knowledge in the Hepatitis B virus (HBV) transcriptional control, and newer technologies emerge that could potentially allow the destruction of cccDNA, exciting new possibilities for curative therapies are discussed.

Keywords: HBV cccDNA; HBV cure; combination therapy; hepatitis B virus.

Publication types

  • Review

MeSH terms

  • Antiviral Agents / pharmacology
  • Antiviral Agents / therapeutic use
  • Combined Modality Therapy
  • DNA, Circular
  • DNA, Viral
  • Disease Management
  • Gene Editing
  • Hepatitis B Surface Antigens / blood
  • Hepatitis B Surface Antigens / immunology
  • Hepatitis B virus / drug effects
  • Hepatitis B virus / metabolism
  • Hepatitis B virus / physiology*
  • Hepatitis B, Chronic / diagnosis
  • Hepatitis B, Chronic / immunology
  • Hepatitis B, Chronic / therapy*
  • Hepatitis B, Chronic / virology*
  • Host-Pathogen Interactions / drug effects
  • Host-Pathogen Interactions / immunology
  • Humans
  • Immunomodulation
  • Treatment Outcome
  • Virus Replication / drug effects

Substances

  • Antiviral Agents
  • DNA, Circular
  • DNA, Viral
  • Hepatitis B Surface Antigens