Seven-Year Treatment Outcome of Entecavir in a Real-World Cohort: Effects on Clinical Parameters, HBsAg and HBcrAg Levels.

OBJECTIVES

We aimed to determine the levels of alanine aminotransferase (ALT), hepatitis B virus DNA (HBV DNA), HBsAg, and a novel viral marker (hepatitis B core-related antigen (HBcrAg)); hepatitis B e antigen (HBeAg) seroconversion and drug resistance rates after 7 years of entecavir treatment in chronic hepatitis B (CHB) patients.

METHODS

Two hundred and twenty-two Chinese CHB patients on continuous entecavir treatment were recruited. Serologic, virologic, biochemical outcomes, and the occurrence of entecavir signature mutations were determined.

RESULTS

The rates of ALT normalization, HBeAg seroconversion, and undetectable HBV DNA were 98.3%, 82.1%, and 98.7%, respectively, after 7 years of entecavir treatment. The genotypic resistance rate was 1.2%. Decline of HBsAg level was modest with a median decline rate of 0.107 log IU/ml/year. Among patients with baseline HBsAg <1,000 IU/ml and annual HBsAg decline rate of ≥0.166 log IU/ml, all have HBsAg of <200 IU/ml (a level highly predictive for HBsAg seroclearance) at year 7. In contrast, in patients with baseline HBsAg ≥1,000 IU/ml and annual HBsAg decline rate of <0.166 log IU/ml, 95.5% had HBsAg of ≥200 IU/ml at year 7. Decline of HBcrAg levels was moderate with a median decline rate of 0.244 log kU/ml/year. Forty-seven patients (32.0%) had undetectable HBcrAg level at year 7.

CONCLUSIONS

Long-term entecavir therapy continued to have good responses with low drug resistance rate. However, the decline of HBsAg with treatment was suboptimal. HBcrAg level declined at a relatively better rate. Baseline HBsAg level of <1,000 IU/ml and annual decline of 0.166 log IU/ml could be used to predict HBsAg response.