title: Hepatitis B virus surface antigen levels: a guide to sustained response to peginterferon alfa-2a in HBeAg-negative chronic hepatitis B.
abstract: We investigated the relationship between hepatitis B virus surface antigen (HBsAg) serum level decline and posttreatment response in patients with hepatitis B e antigen (HBeAg)-negative chronic hepatitis B from a large multinational study of pegylated interferon alfa-2a (peginterferon alfa-2a), with or without lamivudine, versus lamivudine alone. Serum HBsAg was quantified using the Architect assay (Abbott Diagnostics) at pretreatment, end of treatment (week 48), and 6 months after the end of treatment (week 72) in sera from 386 of the 537 patients who participated in the multinational study (peginterferon alfa-2a, 127; peginterferon alfa-2a plus lamivudine, 137; lamivudine monotherapy, 122). Pretreatment HBsAg levels varied according to genotype, with the highest levels present in patients infected with genotypes A (median, 4.11 log(10) IU/mL) and D (median, 3.85 log(10) IU/mL). Significant on-treatment decline in HBsAg was observed during treatment with peginterferon alfa-2a (alone or combined with lamivudine; mean decline at week 48, -0.71 and -0.67 log(10) IU/mL, respectively, P < 0.001), but not during treatment with lamivudine alone (-0.02 log(10) IU/mL). Significantly more patients treated with peginterferon alfa-2a (21%) or peginterferon alfa-2a plus lamivudine (17%) achieved HBsAg levels <100 IU/mL at the end of treatment compared with lamivudine (1%) (both P < 0.001 versus lamivudine). End-of-treatment HBsAg level correlated strongly with HBV DNA suppression to <or=400 copies/mL 6 months posttreatment. An HBsAg level <10 IU/mL at week 48 and on-treatment decline >1 log(10) IU/mL were significantly associated with sustained HBsAg clearance 3 years after treatment (both P < 0.0001).
  
  
  CONCLUSIONS
  On-treatment quantification of HBsAg in patients with HBeAg-negative chronic hepatitis B treated with peginterferon alfa-2a may help identify those likely to be cured by this therapy and optimize treatment strategies.
authors.affiliation: UO Epatologia, Azienda Ospedaliero Universitaria Pisana, Pisa, Italy.
authors.forename: Maurizia Rossana
authors.initials: MR
authors.lastname: Brunetto
authors.forename: Francesco
authors.initials: F
authors.lastname: Moriconi
authors.forename: Ferruccio
authors.initials: F
authors.lastname: Bonino
authors.forename: George K K
authors.initials: GK
authors.lastname: Lau
authors.forename: Patrizia
authors.initials: P
authors.lastname: Farci
authors.forename: Cihan
authors.initials: C
authors.lastname: Yurdaydin
authors.forename: Teerha
authors.initials: T
authors.lastname: Piratvisuth
authors.forename: Kangxian
authors.initials: K
authors.lastname: Luo
authors.forename: Yuming
authors.initials: Y
authors.lastname: Wang
authors.forename: Stephanos
authors.initials: S
authors.lastname: Hadziyannis
authors.forename: Eva
authors.initials: E
authors.lastname: Wolf
authors.forename: Philip
authors.initials: P
authors.lastname: McCloud
authors.forename: Richard
authors.initials: R
authors.lastname: Batrla
authors.forename: Patrick
authors.initials: P
authors.lastname: Marcellin