title: Variant of hepatitis B virus with primary resistance to adefovir.
abstract: The reverse-transcriptase inhibitor lamivudine (Zeffix, GlaxoSmithKline) is often used to treat chronic infection with hepatitis B virus (HBV) until resistance develops. Treatment may then be switched to the reverse-transcriptase inhibitor adefovir (Hepsera, Gilead), which has a lower frequency of resistance. Here, we describe three cases of primary adefovir resistance that were sensitive to tenofovir (Viread, Gilead). All three cases involved a rare HBV variant with a valine at position 233 of the reverse-transcriptase domain instead of isoleucine (rtI233V), as in the wild-type virus. This HBV variant also displayed resistance to adefovir and sensitivity to tenofovir in vitro.
authors.affiliation: Institute of Medical Microbiology and Immunology and the Department of Medicine I, University of Bonn, Bonn, Germany.
authors.forename: Oliver
authors.initials: O
authors.lastname: Schildgen
authors.forename: Hueseyin
authors.initials: H
authors.lastname: Sirma
authors.forename: Anneke
authors.initials: A
authors.lastname: Funk
authors.forename: Cynthia
authors.initials: C
authors.lastname: Olotu
authors.forename: Ulrike C
authors.initials: UC
authors.lastname: Wend
authors.forename: Heinz
authors.initials: H
authors.lastname: Hartmann
authors.forename: Martin
authors.initials: M
authors.lastname: Helm
authors.forename: Jürgen K
authors.initials: JK
authors.lastname: Rockstroh
authors.forename: Wulf R
authors.initials: WR
authors.lastname: Willems
authors.forename: Hans
authors.initials: H
authors.lastname: Will
authors.forename: Wolfram H
authors.initials: WH
authors.lastname: Gerlich
mesh_terms: D000225:Adenine / Q000031:analogs & derivatives* / Q000494:pharmacology / Q000627:therapeutic use; D000595:Amino Acid Sequence; D000998:Antiviral Agents / Q000494:pharmacology / Q000627:therapeutic use; D004279:DNA, Viral / Q000096:biosynthesis; D024882:Drug Resistance, Viral / Q000235:genetics; D005260:Female; D006515:Hepatitis B virus / Q000235:genetics*; D019694:Hepatitis B, Chronic / Q000188:drug therapy* / Q000821:virology; D006801:Humans; D019259:Lamivudine / Q000494:pharmacology / Q000627:therapeutic use; D008297:Male; D008875:Middle Aged; D008969:Molecular Sequence Data; D009154:Mutation; D063065:Organophosphonates / Q000494:pharmacology / Q000627:therapeutic use*; D012194:RNA-Directed DNA Polymerase / Q000235:genetics*; D018894:Reverse Transcriptase Inhibitors / Q000494:pharmacology / Q000627:therapeutic use*; D000068698:Tenofovir; D014766:Viremia
chemical_list: D000998:Antiviral Agents; D004279:DNA, Viral; D063065:Organophosphonates; D018894:Reverse Transcriptase Inhibitors; D019259:Lamivudine; C053001:adefovir; D000068698:Tenofovir; D012194:RNA-Directed DNA Polymerase; D000225:Adenine