Please use this identifier to cite or link to this item: https://ahro.austin.org.au/austinjspui/handle/1/9527
Title: Resistance to adefovir dipivoxil therapy associated with the selection of a novel mutation in the HBV polymerase.
Austin Authors: Angus, Peter W ;Vaughan, Rhys B ;Xiong, Shelly;Yang, Huiling;Delaney, William;Gibbs, Craig;Brosgart, Carol;Colledge, Danielle;Edwards, Rosalind;Ayres, Anna;Bartholomeusz, Angeline;Locarnini, Stephen
Affiliation: Austin Health
Issue Date: 1-Aug-2003
Publication information: Gastroenterology; 125(2): 292-7
Abstract: Adefovir dipivoxil effectively inhibits both hepatitis B virus (HBV) replication and disease activity in patients with chronic hepatitis B. Resistance to treatment was not observed in 2 recent large placebo-controlled 48-week studies with this drug. The aim of this study was to characterize adefovir resistance in a patient who developed clinical and virologic evidence of breakthrough during a 96-week course of treatment.HBV DNA was PCR amplified and sequenced. Phenotypic studies used patient-derived HBV as well as specific mutations created by site-directed mutagenesis of a HBV/baculovirus recombinant.Following the commencement of treatment with adefovir dipivoxil, the patient initially responded with a 2.4 log(10) decrease in serum HBV DNA and normalization of alanine aminotransaminase levels by week 16. During the second year of treatment, however, serum HBV DNA rose progressively, eventually returning to near-pretreatment levels. This increase in viral replication was associated with a marked increase in alanine aminotransferase and mild changes in bilirubin, albumin, and prothrombin time. Comparison of pretreatment and posttreatment HBV DNA by polymerase chain reaction sequencing identified a novel asparagine to threonine mutation at residue rt236 in domain D of the HBV polymerase. In vitro testing of a laboratory strain encoding the rtN236T mutation and testing of patient-derived virus confirmed that the rtN236T substitution caused a marked reduction in susceptibility to adefovir.The development of this novel mutation in the HBV polymerase confers resistance to adefovir dipivoxil. The patient responded to subsequent lamivudine therapy, achieving normalization of alanine aminotransferase and a significant decrease in serum HBV DNA.
URI: https://ahro.austin.org.au/austinjspui/handle/1/9527
ORCID: 
Journal: Gastroenterology
URL: https://pubmed.ncbi.nlm.nih.gov/12891527
Type: Journal Article
Subjects: Adenine.analogs & derivatives.therapeutic use
Alanine Transaminase.blood
Antiviral Agents.therapeutic use
DNA, Viral.blood
DNA-Directed DNA Polymerase.chemistry.genetics
Drug Resistance, Viral
Hepatitis B virus.drug effects.enzymology.genetics
Hepatitis B, Chronic.drug therapy
Humans
Male
Middle Aged
Mutation
Organophosphonates
Viral Proteins.genetics
Appears in Collections:Journal articles

Show full item record

Page view(s)

18
checked on Mar 27, 2024

Google ScholarTM

Check


Items in AHRO are protected by copyright, with all rights reserved, unless otherwise indicated.