OBJECTIVEHBsAg loss and seroconversion in patients with chronic hepatitis B leads to long-lasting good clinical outcomes. The aim of this paper was to investigate to improve the rate of HBsAg loss and seroconversion in chronic hepatitis B patients by prolonged treatment of PEG-IFNa-2a. 217 cases of HBeAg-positive or negative patients were collected from inpatient and outpatient in Beijing Ditan Hospital from May 2005 to October 2009 and subcutaneous injection of 135 ug or 180 ug PEGASYS were given once a week according to body weights. The drug doses were adjusted according to the neutrophilic granulocyte and platelet counts during treatment course. Quantitative HBV DNA test was conducted using a commercially available real-time fluorescence quantitative PCR kit. The serum HBsAg/anti-HBs and HBeAg/anti-HBe were quantitatively detected by Abbott i 2000 chemiluminescent kit before and during treatment every three months. Patients with HBsAg steadily decreased and reached serum HBsAg level below 200 IU/ml after 48 weeks of treatment would receive prolonged treatment. Patients with more than 12 weeks of treatment entered into analysis. Main efficacy of prolonged treatment was evaluated by the incidences of HBsAg loss and seroconversion.

RESULTSThe treatment courses of the 217 patients ranged from 12.0 to 197.6 weeks with an average of 53.1+/-33.4 weeks, 118 cases took more than 48 weeks and another 89 cases less than 48 weeks. 13.4% (29/217) of patients achieved HBsAg loss or HBsAg seroconversion with treatment courses from 17.6 to 197.6 weeks (average 75.4+/-42.8 weeks). Among these 29 patients 24 (82.8%) received more than 48 weeks of treatment, but the treatment courses of HBV DNA reached undetectable level were 20.8+/-8.9 weeks. In this study, 9.5% (14/148) of HBeAg-positive patients achieved HBsAg loss or seroconversion, all of them treated more than 48 weeks, from 48 to 194 weeks, average 81.32+/-39.36 weeks. 21.7% (15/69) of HBeAg-negative patients achieved HBsAg loss or seroconversion, significantly higher than that of HBeAg-positive patients (9.5%) (x2 = 6.129, P = 0.013). The average treatment course for HBeAg-negative patients with HBsAg loss was 70.2+/-48.0 weeks, shorter than that of HBeAg-positive patients with HBsAg loss (81.3+/-39.4 weeks), but no significant difference (t = -0.522, P = 0.602) found between.

CONCLUSIONHigher rate of HBsAg loss and seroconversion could be obtained by individual extended treatment courses in patients with rapid HBV DNA and HBsAg response to PEG-IFNa-2a treatment and the HBeAg-negative patients could got higher rate of HBsAg loss than HBeAg-positive patients.