title: Entecavir plus tenofovir versus entecavir plus adefovir in chronic hepatitis B patients with a suboptimal response to lamivudine and adefovir combination therapy.
abstract: OBJECTIVE
  We compared the efficacies of entecavir (ETV) plus tenofovir (TDF) and ETV plus adefovir (ADV) in chronic hepatitis B (CHB) patients with genotypic resistance to lamivudine (LAM) who showed a suboptimal response to LAM and ADV combination therapy.
  
  
  METHODS
  We reviewed 63 CHB patients with genotypic resistance to LAM who showed a suboptimal response to LAM and ADV combination therapy. Among these patients, 30 were treated with ETV + ADV and 33 were treated with ETV + TDF for 12 months.
  
  
  RESULTS
  The only baseline characteristic that differed significantly between the two groups was the ETV resistance profile. The rate of a virologic response [serum hepatitis B virus (HBV) DNA level of <20 IU/mL] was significant higher for ETV+TDF than for ETV+ADV over 12 months (57.6% vs. 23.3%, P=0.006, at 6 months; 84.8% vs. 26.7%, P<0.001, at 12 months). The probability of a virologic response was significantly increased in ETV+TDF (P<0.001, OR=54.78, 95% CI=7.15-419.54) and decreased in patients with higher baseline viral loads (P=0.001, OR=0.18, 95% CI=0.07-0.50) in multivariate analysis. No serious adverse event occurred during the study period.
  
  
  CONCLUSIONS
  In patients with CHB who showed a suboptimal response to LAM and ADV combination therapy, ETV+TDF was superior to ETV+ADV in achieving a virologic response regardless of the HBV resistance profile. Further large-scale and long-term follow-up prospective studies are needed to explain these results.
authors.affiliation: Division of Gastroenterology and Hepatology, Department of Internal Medicine, CHA University, CHA Gumi Medical Center, Gumi, Korea.
authors.forename: Jung Gil
authors.initials: JG
authors.lastname: Park
authors.affiliation: Division of Gastroenterology and Hepatology, Department of Internal Medicine School of Medicine, Kyungpook National University, Daegu, Korea.
authors.forename: Soo Young
authors.initials: SY
authors.lastname: Park
mesh_terms: D000225:Adenine / Q000031:analogs & derivatives* / Q000627:therapeutic use; D000328:Adult; D000998:Antiviral Agents / Q000627:therapeutic use*; D004279:DNA, Viral / Q000097:blood; D024882:Drug Resistance, Viral; D004359:Drug Therapy, Combination; D005260:Female; D005838:Genotype; D006147:Guanine / Q000031:analogs & derivatives* / Q000627:therapeutic use; D006515:Hepatitis B virus / Q000235:genetics / Q000302:isolation & purification; D019694:Hepatitis B, Chronic / Q000188:drug therapy* / Q000821:virology; D006801:Humans; D019259:Lamivudine / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D063065:Organophosphonates / Q000627:therapeutic use*; D060888:Real-Time Polymerase Chain Reaction; D012189:Retrospective Studies; D000068698:Tenofovir / Q000627:therapeutic use*; D019562:Viral Load
chemical_list: D000998:Antiviral Agents; D004279:DNA, Viral; D063065:Organophosphonates; D019259:Lamivudine; C413685:entecavir; D006147:Guanine; C053001:adefovir; D000068698:Tenofovir; D000225:Adenine
keywords: Chronic hepatitis B; Combination therapy; Entecavir; Lamivudine resistance; Tenofovir