Measurement of hepatitis B virus core-related antigen as predicting factor for relapse after cessation of lamivudine therapy for chronic hepatitis B virus infection

Abstract

Prolonged lamivudine therapy has two major problems: breakthrough hepatitis during treatment and relapse of aminotransferase (ALT) after cessation of the therapy. The aim of this study was to examine factors that could predict ALT flare after stopping lamivudine therapy. We analyzed 22 Japanese patients with chronic hepatitis B infection, in whom lamivudine therapy was stopped after HBV DNA level had been gone undetectable (<3.7LGE/ml) during at least six consecutive months. The post-treatment followed up was carried for 28 months in median (range 9-41). HBV core-related antigen (HBcrAg) assay was assessed using newly developed assay. After cessation of lamivudine therapy, 11 patients (50%) had relapsed (reactivation of serum ALT >80IU/l, relapsers) and remaining 11 (50%) did not relapse (non-relapsers). In the univariate comparison of relapsers versus non-relapsers, HBcrAg level at lamivudine cessation point (4.5+/-1.0 versus 3.4+/-0.9; p=0.0145) has been shown as a significant predictive factor for non-relapse. All patients with HBcrAg <3.0logU/ml at the cessation point had no ALT flares. Multivariate analysis on effects of 10 factors (age, sex, cirrhosis, pretreatment ALT level, HBV DNA level, HBcrAg level, mean months till undetectable HBV DNA, duration of undetectable HBV DNA and HBcrAg level at lamivudine cessation point), indicated that HBcrAg level at lamivudine cessation point <3.4log U/ml was the only independent predictive factor for absence of the post-treatment relapse. HBcrAg level at lamivudine cessation point might be useful as a prognostic predictor of response to lamivudine therapy cessation. The measurement of HBcrAg is a useful additional test for monitoring chronic HBV infection.