The Level of HBV DNA at Month 12 Is an Important Predictor of Virological Breakthrough During Adefovir Monotherapy in Chronic Hepatitis B Patients with Lamivudine Resistance

Background and Aims The aim of this study was to determine the optimal time and HBV DNA levels during the treatment period for prediction of virological breakthrough (VBT) 3 years after adefovir monotherapy in chronic hepatitis B (CHB) patients with lamivudine resistance. Methods We consecutively analyzed HBV DNA levels within 12 months in 210 lamivudine-resistant CHB patients treated with adefovir monotherapy for more than 36 months. Results VBT, genotypic adefovir mutations, and virologic responses were observed in 52 (24.8%), 37 (17.6%), and 117 (55.7%) cases within 3 years of treatment, respectively. Using receiver-operating characteristic curve analysis, HBV DNA levels at month 12 had a greater power (AUROC, 0.839; 95% CI, 0.759–0.919; p