Abstract: Objective To investigate clinical characteristics of hepatitis B e antigen (HBeAg) -positive chronic hepatitis B (CHB) patients developed telbivudine resistance. Methods Clinical data of HBeAg-positive CHB patients receiving telbivudine monotherapy at baseline, during treatment and at virological breakthrough was analyzed for investigating clinical characteristics of telbivudine resistance. Results The median time of virological breakthrough occurrence in patients developed telbivudine resistance was 78 weeks. Levels of serum hepatitis B virus (HBV) DNA and alanine aminotransferase (ALT) were significantly lower in patients at virological breakthrough than that at baseline. There was a significant difference in HBV DNA levels between patients with single-site and multiple-site drug resistance mutations when virological breakthrough occurred (u=315.50, P=0.03). Eight drug resistance mutation sites and 11 combination patterns were detected, all containing M204I site mutation. Between telbivudine-resistant group and control group, there were statistically significant differences in age, gender, baseline levels of HBeAg and ALT. Rates of HBV DNA undetectable, HBeAg loss and HBeAg seroconversion in telbivudine-resistant group were significantly lower than those in control group at week 12 and week 24, respectively. Conclusion Patients of older age, male gender, lower baseline levels of HBeAg and ALT were predisposed to develop telbivudine resistance. However, patients who achieved virological and serological response in the early stages are unlikely to develop telbivudine resistance.

Key words: Chronic hepatitis B, Telbivudine, Antiviral therpay, Drug resistance mutation