Identification and characterization of mutations in hepatitis B virus resistant to lamivudine


  • The Lamivudine Clinical Investigative Group includes: Jules L. Dienstag, Massachusetts General Hospital, Gastrointestinal Unit, Boston, MA; Gary Levy, The Toronto Hospital, Toronto, Ontario, Canada; Paul Martin, University of California at Los Angeles, School of Medicine, Los Angeles, CA; Mack Mitchell, Chairman, Department of Medicine, Greater Baltimore Medical Center, Baltimore, MD; Robert Perillo, Alton L. Ochsner Clinic, New Orleans, LA; Jorge Rakela, Chief, Division of Transplantation Medicine, University of Pittsburgh Medical Center, Pittsburgh, PA; Jean Pierre Villeneuve, Hospital St. Luc, Montreal, Quebec, Canada; Prof. Elwyn Elias, Queen Elizabeth Hospital, Edgbaston, Birmingham, England; Prof. Dr. med. Michael Manns, Direktor der Abteilung Gastro und Hepatologie, Medizinische Hochschule Hannover, Zentrum Innere Medizin und Dermatologie, Hannover, Germany; Prof. Dr. S.W. Schalm, Department of Internal Medicine II, Dijkzigt Hospital, Section Hepatology, Rotterdam, The Netherlands; Vince Bain, Department of Medicine, Division of Gastroenterology, University of Alberta, Edmonton, Alberta, Canada; Shuhei Nishiguchi, Third Department of Internal Medicine, Osaka City University Medical School, Osaka, Japan


Cirrhosis and hepatocellular carcinoma occur as long-term complications of chronic hepatitis B virus (HBV) infection. Antiviral therapy is potentially a successful approach for the treatment of patients with HBV infection, which includes the nucleoside analog, lamivudine [(-)2′-deoxy-3′-thiacytidine, 3TC]. Although resistance to lamivudine therapy has been reported in several HBV-infected patients, the pattern of resistance-associated mutations in HBV has not been fully characterized. We report a DNA sequence database that includes a 500–base pair region of the HBV polymerase gene from 20 patients with clinical manifestations of lamivudine resistance. Analysis of the database reveals two patterns of amino acid substitutions in the tyrosine, methionine, aspartate, aspartate (YMDD) nucleotide-binding locus of the HBV polymerase. HBV DNA from the sera of patients in Group I exhibits a substitution of valine for methionine at residue 552, accompanied by a substitution of methionine for leucine at residue 528. Patients in Group II had only an isoleucine-for-methionine substitution at position 552. Reconstruction of these mutations in an HBV replication–competent plasmid was performed in a transient transfection cell assay to determine the function/relevance of these mutations to lamivudine resistance. Both Group I and Group II mutations resulted in a substantial decrease in sensitivity to lamivudine treatment (>10,000-fold shift in IC50 over wild-type [wt] IC50), strongly indicating that these mutations were involved in resistance to lamivudine. A hypothetical model of the HBV reverse transcriptase has been generated for further study of the role of these mutations in lamivudine resistance.