Linked Life Data

15259898

Source:http://linkedlifedata.com/resource/pubmed/id/15259898

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
2004-7-19
pubmed:abstractText
Emergence of lamivudine-resistant hepatitis B virus (HBV) is a major concern in human immunodeficiency virus (HIV) and HBV coinfected patients. Following selection of resistant mutants, hepatitis flare or rapid progression to cirrhosis may occur. Treatment of patients with new nucleotide analogues such as adefovir dipivoxil (ADV) or tenofovir disoproxil fumarate (TDF) has shown good efficacy in controlling wild-type or lamivudine-resistant HBV replication. The purpose of this study was to assess the in vitro efficacy of new nucleotide analogues on HBV strains isolated from lamivudine-treated patients. After purification of HBV DNA from patient sera, the whole HBV genome was PCR-amplified and cloned. Drug sensitivity was measured after transfection of the isolated full genomes into HepG2 cells and measurement of HBeAg, HBsAg and viral replication in the culture media under increasing drug concentrations. A wild-type strain isolated from an untreated patient served as control. In a clinical study of ADV (Gilead 460i study), seven of the 35 patients carried HBV strains with the triple lamivudine resistance-associated amino-acid changes rtV173L/L180M/M204V at baseline. Although all patients responded to ADV in this clinical study, the serum HBV reduction was lower in the seven patients with the triple mutation (median -3.3 log copies/ml) compared to the patients who had only the rtL180M/M204V mutations (median -4.1 log copies/ml) at week 48 (P=0.04, Mann-Whitney test). In our in vitro system, lamivudine IC50 on lamivudine-resistant HBV carrying amino-acid substitutions rtL180M and rtM204V within the polymerase encoding region increased by more than 16,000-fold (from 6 nM to over 100 microM) when compared to wild-type HBV. For ADV and TDF, comparison of wild-type and lamivudine-resistant HBV IC50 (rtL180M-M204V) showed, respectively, 2.85-fold (from 0.07 to 0.2 microM) and 3.3-fold (from 0.06 to 0.2 microM) increases, indicating a mild decrease of both drug activities, in vitro. At the ADV concentration of 0.1 microM, presence of the V173L mutation reduced the inhibition of HBsAg production from 50 to 30% (P<0.01) and the viral replication from 45 to 32% (P<0.01, Mann-Whitney). Conversely, tenofovir had similar potency on both HBV mutation profiles with 60% inhibition of HBsAg production and 45% inhibition of viral replication at 0.1 microM. Our study supports the high efficacy of ADV and TDF seen in patients after lamivudine breakthrough. The excellent activity of TDF on lamivudine-resistant virus independently of the resistance mutation profile offers an interesting treatment alternative to HIV-HBV coinfected patients.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
1359-6535
pubmed:author
pubmed:issnType
Print
pubmed:volume
9
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
353-63
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed-meshheading:15259898-Adenine, pubmed-meshheading:15259898-Adult, pubmed-meshheading:15259898-Antiviral Agents, pubmed-meshheading:15259898-Cell Line, pubmed-meshheading:15259898-DNA, Viral, pubmed-meshheading:15259898-DNA-Directed DNA Polymerase, pubmed-meshheading:15259898-Dose-Response Relationship, Drug, pubmed-meshheading:15259898-Drug Resistance, Viral, pubmed-meshheading:15259898-HIV Infections, pubmed-meshheading:15259898-Hepatitis B, pubmed-meshheading:15259898-Hepatitis B Surface Antigens, pubmed-meshheading:15259898-Hepatitis B e Antigens, pubmed-meshheading:15259898-Hepatitis B virus, pubmed-meshheading:15259898-Humans, pubmed-meshheading:15259898-Lamivudine, pubmed-meshheading:15259898-Middle Aged, pubmed-meshheading:15259898-Mutation, pubmed-meshheading:15259898-Phosphonic Acids, pubmed-meshheading:15259898-Reverse Transcriptase Inhibitors, pubmed-meshheading:15259898-Transfection, pubmed-meshheading:15259898-Virus Replication
pubmed:year
2004
pubmed:articleTitle
In vitro susceptibility of lamivudine-resistant hepatitis B virus to adefovir and tenofovir.
pubmed:affiliation
Virology, AP-HP Pitie-Salpetriere Hospital, Paris, France.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, Non-U.S. Gov't