Curbside Consultation of the Liver: 49 Clinical Questions

Mitchell L. Shiffman, MD

Question 12: How Do I Know When A Patient Receiving An Oral Antiviral Agent Has Developed Resistance And What Do I Do When This Happens? (continued)

Mitchell L. Shiffman, MD

Resistance is the major limitation when utilizing an oral antiviral agent for the treatment of chronic hepatitis B virus (HBV). Although it is commonly believed that resistant mutations develop in response to treatment with antiviral agents, the great majority of mutations that convey resistance to antiviral therapy are actually preexisting.1 Mutations are single nucleotide substitutions (SNPs) that occur in the viral genome. This changes the nucleic acid sequence of a viral gene. In many cases these SNPs have no effect on the amino acid sequence, structure, or function of the protein…