HBsAg Quantification Predicts Off-treatment Response To Interferon In Chronic Hepatitis B Patients

Background:At present,two kinds of drugs for the treatment of chronic hepatitis B(CHB)include oral nucleoside(acid)drugs(NAS)and interferon(IFN).The advantage of interferon is that the clearance rate of HBsAg and the seroconversion rate of HBeAg are higher than that of NAS.[4-9]At present,the understanding on end-of-treatment(EOT)HBsAg level predicting post-treatment response to IFN is still finite.t21]Objective:to predict post-treatment response according to end-of-treatment(EOT)HBsAg level in the treatment of CHB with IFNMethods:Patients with CHB infection and treated with IFN-based therapy during the period from December 2010 to December 2017 at Nanfang Hospital were enrolled in this study.Serum HBsAg levels at EOT were measured to evaluate the associations between EOT HBsAg levels(Group 1,HBsAg>0.05 and ?10 IU/mL;Group 2,HBsAg>10 and<200 IU/mL;Group 3,HBsAg>200 IU/mL)with post-treatment HBsAg loss.Results:The average HBsAg level was 2.4±1.7 1gIU/ml at the time of discontinuation.22.4%of patients had HBsAg level>0.05 IU/ml and?10IU/ml.The cumulative negative rates of HBsAg in group 1,2 and 3 were 30.4%,9.8%and 0%respectively(P<0.001).The negative predictive value of HBsAg clearance was 97.9%when HBsAg>10IU/ml.The Apri of the three groups were statistically different in the fifth year of follow-up.The patients with HBsAg?10IU/ml had the lowest Apri(0.2±0.1,P=0.043).and there was no statistical difference between the long-term outcome of HBsAg?10IU/ml and HBsAg clearance.Patients who achieved HBsAg clearance after discontinuation were significantly correlated with low baseline HBsAg level(P<0.001),decrease of HBsAg11g IU/ml at 24 weeks of treatment(P=0.001),and discontinuation of HBsAg?10 IU/ml(P=0.001).Patients with high baseline ALT(P= 0.016),low HBV DNA(P=0.004),low HBsAg(P=0.019),more than 11g IU/ml decrease in HBsAg after 24 weeks of treatment(P<0.001)and more than 21g IU/ml decrease in HBV DNA(P=0.001)were more likely to reach HBsAg ?10 IU/ml when IFN was stopped.In group 1,the mean dynamic level of HBsAg was less than 10IU/ml during the follow-up period,in which 5.3%,12.5%,21.4%,25%,26.8%and 30.4%of the patients in half a year,one year,two years,three years,four years and five years after the drug withdrawal achieved HBsAg clearance,and no relapse was observed during the follow-up period.Conclusion:EOT HBsAg level?10 IU/mL was found to lead to high rate of post-treatment HBsAg loss.For patients without willingness to extend IFN treatment,off-treatment follow-up could be considered when HBsAg level decreased to?10IU/mL.