[Low-levels of HBsAg quantification at 48-week in HBeAg-negative chronic hepatitis B patients are the advantageous population for HBsAg clearance]

Objective: To analyze the therapeutic effect on HBeAg-negative chronic hepatitis B patients treated with Peg-IFNα-2a combined with NAs to obtain the influencing factors for predicting HBsAg clearance. Methods: A retrospective study was conducted to investigate the effect of pegylated interferon alpha-2a combined with nucleoside analogues (lamivudine/adefovir dipivoxil) on HBeAg-negative chronic hepatitis B. The treatment course was 96 weeks. Patients were followed up 120 weeks after the treatment. HBsAg clearance at 120 weeks was taken as the objective of the study. Logistic regression and receiver operating characteristic curve analysis screened the related factors affecting HBsAg clearance. χ (2) test was used to compare count data. Results: 111 patients were treated with pegylated interferon alpha-2a combined with nucleoside analogues, and 107 patients completed the scheduled course of treatment and follow-up. HBsAg clearance rate at120 week was 29.0% (31/107). The influencing factors for analysis were: (1) gender had no effect on HBsAg clearance rate; age and baseline levels of HBV DNA and alanine aminotransferase had no significant effect on HBsAg clearance; low baseline level of HBsAg (< 3.023 lgIU/ml) was beneficial to HBsAg clearance. The area under the working characteristic curve of the subjects was 0.746, the positive predictive value was 44.4%, and the negative predictive value was 86.8%. (2) HBsAg quantification or decline in 24 weeks and 48 weeks of treatment had a good predictive effect on HBsAg clearance, and the 48 weeks predicted value was higher than 24 weeks. When the HBsAg quantification was≤2.070 lgIU/ml at 48 weeks, the area under the receiver operating characteristic curve was 0.931, the positive predictive value was 52.8%, and the negative predictive value was 94.4%. When HBsAg decreased from baseline to≥0.991 lgIU/ml, the area under the receiver operating characteristic curve was 0.888, the positive predictive value was 50.8%, and the negative predictive value was 97.9%. (3) The analysis of HBsAg subgroup levels at 48 weeks suggested that the "interval analysis" can forecast HBsAg clearance more exactly than "nodal analysis" .The final HBsAg clearance rate of 100 IU/ml < HBsAg≤1 000 IU/ml, 10 IU/ml < HBsAg≤100 IU/ml and HBsAg≤10 IU/ml groups reached 6.7%, 31.8% and 67.7%, respectively. (4) The ALT abnormal group in the course of treatment obtained a higher HBsAg clearance rate (48.0%, 12/25). Conclusion: 96-weeks long-term treatment with pegylated interferon-alpha -alpha-2a combined with nucleoside analogues for HBeAg-negative chronic hepatitis B has a good predictive value for HBsAg clearance at baseline and during treatment. The "interval level" of HBsAg at 48-weeks is more accurate in predicting HBsAg clearance, suggesting that HBeAg-negative chronic hepatitis B patients with low HBsAg levels at 48-weeks are the advantageous populations with HBsAg clearance. These patients are worthy of prolonged treatment to pursue "clinical cure".