title: Use of quantitative serum HBsAg for optimization of therapy in chronic hepatitis B patients treated with pegylated interferon alfa-2a: a Romanian cohort study.
abstract: OBJECTIVE
  The aim of the study was to assess the clinical utility of serum HBsAg quantification as a surrogate biomarker for the prediction of sustained virological response (SVR) in chronic hepatitis B (CHB) patients treated with Pegylated Interferon alfa-2a (Peg-IFN α-2a).
  
  
  METHODS
  We performed a prospective cohort study which included 57 patients with CHB treated 48 weeks with Peg-IFN α-2a and followed for another 24 weeks. HBsAg was quantified at the baseline, during treatment and at the end of follow-up. SVR was defined as HBV-DNA below 2,000 IU/ml at 24 weeks after the end of therapy.
  
  
  RESULTS
  The majority of patients had HBeAg-negative CHB (68%, n=39). Positive predictive factors for SVR at baseline were low levels of HBsAg (3.72 log10 IU/ml, p=0.032) and HBV-DNA (3.96 log10 IU/ml, p=0.035). During treatment, patients who achieved SVR showed a marked decrease in serum HBsAg in comparison with nonresponders (at week 48 mean decrease of 1.06 +/- 1.3 log10 IU/ml versus 0.04 ± 0.5 log10 UI/ml, p=0.005). On therapy, HBV-DNA reduction ≥ 2 log10 IU/ml with any decrease of HBsAg level at week 12 had a positive predictive value (PPV) of 80% (95% CI: 51.91-95.43%) for SVR, while HBV-DNA decline < 2 log10 IU/ml without any decline of HBsAg had a negative predictive value (NPV) of 85.71% (95% CI: 42.23-97.63%) for SVR.
  
  
  CONCLUSIONS
  HBsAg quantification combined with HBV-DNA assessment could become an early useful tool to optimize the management of CHB patients treated with Peg-IFN α-2a, according to response guided therapy.
authors.affiliation: Central Military Emergency Hospital Dr Carol Davila; National Institute of Infectious Diseases Prof Dr Matei Bals, Bucharest, Romania; Email:gvaleriu21@yahoo.com.
authors.forename: Valeriu I
authors.initials: VI
authors.lastname: Gheorghiţa
authors.forename: Florin Alexandru
authors.initials: FA
authors.lastname: Caruntu
authors.forename: Manuela
authors.initials: M
authors.lastname: Curescu
authors.forename: Ioana
authors.initials: I
authors.lastname: Olaru
authors.forename: Monica Nicoleta
authors.initials: MN
authors.lastname: Radu
authors.forename: Gabriel
authors.initials: G
authors.lastname: Colţan
authors.forename: Adrian
authors.initials: A
authors.lastname: Streinu-Cercel
mesh_terms: D000328:Adult; D000465:Algorithms; D000998:Antiviral Agents / Q000627:therapeutic use*; D015415:Biomarkers / Q000097:blood; D015331:Cohort Studies; D004279:DNA, Viral / Q000097:blood; D016903:Drug Monitoring / Q000379:methods; D005260:Female; D006514:Hepatitis B Surface Antigens / Q000097:blood*; D006515:Hepatitis B virus / Q000302:isolation & purification; D019694:Hepatitis B, Chronic / Q000188:drug therapy* / Q000821:virology; D006801:Humans; D016898:Interferon-alpha / Q000627:therapeutic use*; D008297:Male; D011092:Polyethylene Glycols / Q000627:therapeutic use*; D011446:Prospective Studies; D011994:Recombinant Proteins / Q000627:therapeutic use; D016896:Treatment Outcome; D019562:Viral Load; D055815:Young Adult
chemical_list: D000998:Antiviral Agents; D015415:Biomarkers; D004279:DNA, Viral; D006514:Hepatitis B Surface Antigens; D016898:Interferon-alpha; D011994:Recombinant Proteins; D011092:Polyethylene Glycols; C100416:peginterferon alfa-2a