No detectable resistance to tenofovir disoproxil fumarate after 6 years of therapy in patients with chronic hepatitis B.

Unlabelled: One major challenge in the treatment of chronic hepatitis B is to maintain long-term viral suppression without promoting the selection of drug-resistant mutations. We analyzed data from 347 hepatitis B e antigen-negative and 238 hepatitis B e antigen positive patients receiving tenofovir disoproxil fumarate (TDF) in an open-label, longterm extension of two phase 3 studies. To date, resistance analyses have been completed for patients receiving up to 288 weeks (6 years) of TDF.

Evaluation of anti-HBV drug resistant mutations among patients with acute symptomatic hepatitis B in the United States.

Background & Aims: Reported HBV drug resistance mutations among previously untreated patients with chronic hepatitis B are variable. Whether resistant HBV strains are transmitted in the acute setting is uncertain. We sought to document the presence of antiviral resistance (AVR) mutations in patients with acute HBV (AHB) infection.

No resistance to tenofovir disoproxil fumarate detected after up to 144 weeks of therapy in patients monoinfected with chronic hepatitis B virus.

Unlabelled: Tenofovir disoproxil fumarate (TDF) is a nucleotide analogue with potent activity against human immunodeficiency virus type 1 and hepatitis B virus (HBV). To date, no reports of HBV clinical resistance to TDF have been confirmed. In two phase 3 studies (GS-US-174-0102 and GS-US-174-0103), 375 hepatitis B e antigen-negative (HBeAg(-) ) patients and 266 HBeAg(+) patients with chronic hepatitis B (some nucleoside-naive and some lamivudine-experienced) were randomized 2:1 to receive TDF (n = 426) or adefovir dipivoxil (ADV; n = 215) for 48 weeks.

Three-year efficacy and safety of tenofovir disoproxil fumarate treatment for chronic hepatitis B.

Background & Aims: Tenofovir disoproxil fumarate (TDF), a nucleotide analogue and potent inhibitor of hepatitis B virus (HBV) polymerase, showed superior efficacy to adefovir dipivoxil in treatment of chronic hepatitis B through 48 weeks. We evaluated long-term efficacy and safety of TDF monotherapy in patients with chronic hepatitis B who were positive or negative for hepatitis B e antigen (HBeAg(+) or HBeAg(-)).

Methods: After 48 weeks of double-blind comparison of TDF to adefovir dipivoxil, patients who underwent liver biopsy were eligible to continue the study on open-label TDF for 7 additional years; data presented were collected up to 3 years (week 144) from 85% of participants.

Tenofovir is effective alone or with emtricitabine in adefovir-treated patients with chronic-hepatitis B virus infection.

Background & Aims: We compared treatments for patients with chronic hepatitis B virus (HBV) infection who had an incomplete response to adefovir dipivoxil (ADV). We evaluated a combination of fixed-dose emtricitabine (FTC) and tenofovir disoproxil fumarate (TDF) from the start (early combination) versus TDF as monotherapy.

Methods: Patients (n = 105) were randomly assigned to groups given TDF (n = 53) or FTC/TDF (n = 52).

Tenofovir disoproxil fumarate versus adefovir dipivoxil for chronic hepatitis B.

Background: Tenofovir disoproxil fumarate (DF) is a nucleotide analogue and a potent inhibitor of human immunodeficiency virus type 1 reverse transcriptase and hepatitis B virus (HBV) polymerase.

Methods: In two double-blind, phase 3 studies, we randomly assigned patients with hepatitis B e antigen (HBeAg)-negative or HBeAg-positive chronic HBV infection to receive tenofovir DF or adefovir dipivoxil (ratio, 2:1) once daily for 48 weeks. The primary efficacy end point was a plasma HBV DNA level of less than 400 copies per milliliter (69 IU per milliliter) and histologic improvement (i.

Sustained hepatitis B e antigen seroconversion in patients with chronic hepatitis B after adefovir dipivoxil treatment: analysis of precore and basal core promoter mutants.

Background: This study evaluated the persistence of hepatitis B e antigen (HBeAg) seroconversion (which is considered to be an important therapeutic end point) after adefovir dipivoxil treatment.

Methods: Forty-five patients who experienced confirmed HBeAg seroconversion and had a serum hepatitis B virus DNA level < 10(5) copies/mL while receiving 10 mg of adefovir dipivoxil in a prior study were enrolled in the present study. At the time of the last dose of adefovir dipivoxil (baseline), the median age of the patients was 35 years, 64% were male, 73% were Asian, 27% were white, the median alanine aminotransferase level was 25 IU/L, and the median serum hepatitis B virus DNA level was 3.

In vitro drug susceptibility analysis of hepatitis B virus clinical quasispecies populations.

Analysis of the replication and drug resistance of patient serum hepatitis B virus (HBV) populations can contribute to the therapeutic management of chronic hepatitis B. We developed a procedure for cloning serum HBV quasispecies populations and for phenotypic analysis of the cloned populations for in vitro drug susceptibility. Equivalent sequences were compared to the respective serum HBV DNAs of the cloned quasispecies by population sequencing.