Genotypic resistance profiles in Chinese patients with chronic hepatitis B virus infection and the efficacy of nucleoside analog rescue therapy

BACKGROUND AND AIMS The aims of this study were to explore the correlation between chronic hepatitis B virus (HBV) drug-resistant mutation profiles and the efficacy of nucleoside analog rescue therapy in patients with initial antiviral treatment failure. PATIENTS AND METHODS Patients with initial antiviral therapy failure were recruited between January 2011 and January 2013 from the Division of Infectious Disease, West China Hospital, Sichuan University, Chengdu, People's Republic of China. Following drug-resistant mutation testing, eligible patients received nucleoside analog rescue therapy for 24 weeks. The primary endpoint was rescue therapy efficacy, and the secondary endpoint was adverse events. RESULTS We recruited 168 patients with chronic HBV infection who had initial antiviral treatment failure. Eighty-nine patients (52.98%) experienced virological breakthrough (group A); 79 patients (47.02%) had partial/null response (group B). Among the patients, 102 (102/168, 60.7%) carried at least one HBV drug resistance mutation. The prevalence of genotypic resistance was significantly higher in group A than in group B (P<0.001). In addition, 118 patients (118/168, 70.2%) achieved undetectable serum HBV DNA with the nucleoside analog rescue therapy. Rescue therapy (P=0.002) and no evidence of genotypic resistance (P=0.001) were related to a higher rate of virological response. CONCLUSION These data indicate that patients with chronic HBV infection who have initial antiviral therapy failure with or without signs of genotypic resistance may still stand a chance of gaining therapeutic benefit with nucleoside analog rescue therapy.