title: Efficacy of tenofovir disoproxil fumarate to prevent vertical transmission in mothers with lamivudine-resistant HBV.
abstract: BACKGROUND
  In China, women with chronic HBV infection and who are of childbearing age receive lamivudine at an early age. Thus, viral resistance becomes a challenge for intervention to prevent mother-to-infant transmission. We prospectively assessed the efficacy of tenofovir in pregnant women with lamivudine-resistant HBV.
  
  
  METHODS
  Chronic HBV-infected mothers resistant to lamivudine were enrolled. Tenofovir was administrated at gestation weeks 24 or 28. Virological and biochemical parameters were assessed. All infants received combined immunoprophylaxis and were followed for 1 year.
  
  
  RESULTS
  Of the 48 mothers enrolled, 21 started tenofovir therapy at gestation week 24 and 27 started at week 28. Tenofovir resulted in an HBV DNA decline of 5.23 ± 1.68 log10 IU/ml at delivery. The group starting therapy at week 24 exhibited a more rapid viral inhibition (P<0.001) and more significant HBV DNA load decline (5.89 ± 1.66 versus 4.72 ± 1.55; P=0.019) than the group starting at week 28. At delivery, all mothers had a viral titre <10(6) IU/ml, 76.2% from the week 24 starting group displayed virus <10(4) IU/ml, and 52.4% showed undetectable virus at delivery, much higher than the week 28 starting group (29.6%), although there was no statistically significant difference in viral levels at delivery between the two groups. Congenital abnormalities and neonatal growth were comparable to the normal population. No case of perinatal transmission was diagnosed.
  
  
  CONCLUSIONS
  This investigation clarifies the efficacy of tenofovir for reducing vertical transmission of HBV in mothers with lamivudine-resistant HBV and demonstrates that tenofovir is well-tolerated in the second and third trimesters.
authors.affiliation: Department of Infectious Disease, the First Affiliated Hospital of Medical College, Xi'an Jiaotong University, Xi'an, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Wang
authors.forename: Jinfeng
authors.initials: J
authors.lastname: Liu
authors.forename: Caijing
authors.initials: C
authors.lastname: Qi
authors.forename: Taotao
authors.initials: T
authors.lastname: Yan
authors.forename: Furong
authors.initials: F
authors.lastname: Cao
authors.forename: Li
authors.initials: L
authors.lastname: Jin
authors.forename: Yingli
authors.initials: Y
authors.lastname: He
authors.forename: Yuan
authors.initials: Y
authors.lastname: Yang
authors.forename: Shulin
authors.initials: S
authors.lastname: Zhang
authors.forename: Tianyan
authors.initials: T
authors.lastname: Chen
authors.forename: Yingren
authors.initials: Y
authors.lastname: Zhao
mesh_terms: D000328:Adult; D000998:Antiviral Agents / Q000494:pharmacology / Q000627:therapeutic use*; D015415:Biomarkers; D024882:Drug Resistance, Viral; D005260:Female; D005500:Follow-Up Studies; D006509:Hepatitis B / Q000175:diagnosis / Q000188:drug therapy* / Q000517:prevention & control / Q000635:transmission* / Q000821:virology; D017325:Hepatitis B Vaccines / Q000008:administration & dosage; D006515:Hepatitis B virus / Q000187:drug effects*; D019694:Hepatitis B, Chronic / Q000188:drug therapy / Q000635:transmission / Q000821:virology; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D018445:Infectious Disease Transmission, Vertical / Q000517:prevention & control*; D019259:Lamivudine / Q000494:pharmacology / Q000627:therapeutic use; D008297:Male; D011247:Pregnancy; D011251:Pregnancy Complications, Infectious; D000068698:Tenofovir / Q000494:pharmacology / Q000627:therapeutic use*; D016896:Treatment Outcome; D019562:Viral Load; D014779:Virus Replication / Q000187:drug effects
chemical_list: D000998:Antiviral Agents; D015415:Biomarkers; D017325:Hepatitis B Vaccines; D019259:Lamivudine; D000068698:Tenofovir