Tenofovir disoproxil fumarate rescue therapy following failure of both lamivudine and adefovir dipivoxil in chronic hepatitis B

Gut. 2011 Feb;60(2):247-54. doi: 10.1136/gut.2010.223206. Epub 2010 Oct 29.

Abstract

Objective: To determine the efficacy of tenofovir disoproxil fumarate (TDF) in adults with chronic hepatitis B virus (HBV) infection who had previously failed lamivudine (LAM) and had significant viral replication (HBV DNA >10⁵ copies/ml if HBeAg positive, > 10⁴ copies/ml if HBeAg negative) despite at least 24 weeks of treatment with adefovir dipivoxil (ADV).

Design: A prospective open-label study of TDF 300 mg daily. Patients receiving combination ADV/LAM prior to baseline were switched to TDF/LAM.

Setting: Multiple tertiary referral centres.

Methods: Sixty patients were enrolled. The median age was 48.5 years (range 21e80), 46 (77%) were male and 40 (67%) were HBeAg positive. Thirty-eight patients (63%) were switched from ADV to TDF, the remainder from ADV/LAM to TDF/LAM. At baseline, substitutions conferring resistance to LAM or ADV were present in 20 patients (33%) and 17 patients (28%), respectively. The median baseline viral load was 5.33 log₁₀ IU/ml (range 2.81-8.04). Patients initially treated with TDF monotherapy with persistent viral replication at or after 24 weeks were switched to TDF/LAM. The main outcome measures were change in HBV viral load from baseline and percentage of patients achieving an undetectable viral load (<15 IU/ml).

Results: Results are reported at 96 weeks of treatment. One patient discontinued TDF at 10 days due to rash. The time-weighted change in viral load from baseline to week 12 was -2.19 log10 IU/ml overall. The median change in HBV DNA from baseline to weeks 12, 24, 48 and 96 was -2.86, -3.23, -3.75 and -4.03 log₁₀ IU/ml, respectively. At 48 and 96 weeks, 27/59 (46%) and 38/59 (64%) patients achieved a HBV DNA <15 IU/ml. The response was independent of baseline LAM therapy or mutations conferring ADV resistance.

Conclusions: In heavily pretreated patients with a high rate of genotypic resistance, TDF retains significant activity against HBV although this appears diminished in comparison with studies of naïve patients.

Publication types

  • Clinical Trial
  • Multicenter Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenine / adverse effects
  • Adenine / analogs & derivatives*
  • Adenine / therapeutic use
  • Adult
  • Aged
  • Aged, 80 and over
  • DNA, Viral / blood
  • Drug Resistance, Viral / genetics
  • Epidemiologic Methods
  • Female
  • Hepatitis B virus / drug effects
  • Hepatitis B virus / genetics
  • Hepatitis B virus / isolation & purification
  • Hepatitis B, Chronic / drug therapy*
  • Hepatitis B, Chronic / virology
  • Humans
  • Lamivudine / therapeutic use
  • Male
  • Middle Aged
  • Mutation
  • Organophosphonates / adverse effects
  • Organophosphonates / therapeutic use*
  • Reverse Transcriptase Inhibitors / adverse effects
  • Reverse Transcriptase Inhibitors / therapeutic use*
  • Salvage Therapy / methods*
  • Tenofovir
  • Treatment Failure
  • Treatment Outcome
  • Viral Load
  • Young Adult

Substances

  • DNA, Viral
  • Organophosphonates
  • Reverse Transcriptase Inhibitors
  • Lamivudine
  • adefovir
  • Tenofovir
  • Adenine