BACKGROUND/AIMS: Entecavir (ETV) is effective and safe antiviral agent against hepatitis B virus (HBV) in clinical and real-world setting but, most studies were performed in single institute or have limitation in patient's number. A large-scale nation-wide real-world surveillance study was carried out to investigate safety, efficacy and clinical effectiveness of ETV in Korean patients with chronic hepatitis B (CHB). METHODS: Between 2006 and 2012, 3,444 patients were enrolled from 132 Korean institutions. For the safety assessment, investigators recorded the occurrence of observed and patient-reported adverse events (AEs), as well as laboratory abnormalities. Efficacy, which consisted of change in HBV DNA and alanine aminotransferase (ALT), was evaluated in patients who had received at least 16 weeks of ETV treatment. Overall clinical effectiveness, based on improvement of ALT, HBV DNA and patient's symptoms, was evaluated by physicians. RESULTS: Of the patients, 3,367 were evaluated for safety and 3,115 for efficacy and clinical effectiveness. Three hundred and eighty AEs were reported in 255 cases (7.57%), and 67 adverse drug reactions in 54 cases (1.6%). Serious AEs (SAE) were 19 events in nine cases (0.27%). Serious adverse drug reactions (SADR) were three events in two cases (0.06%), and unexpected SAE/SADR were three events in two cases (0.06%). Medical history and concomitant medications were factors inf luencing incidence rates of AEs. Overall clinical effectiveness rate was 96.53%, which was clinically assessed as marked improved or improved state. CONCLUSIONS This study showed that ETV was well tolerated and clinically effective in Korean patients with CHB in a real-world nation-wide setting.

BACKGROUND/AIMS: Long-term data on antiviral therapy in Korean patients with hepatitis B e antigen (HBeAg)-negative chronic hepatitis B (CHB) are limited. This study evaluated the efficacy and safety of entecavir (ETV) and lamivudine (LAM) over 240 weeks. METHODS: Treatment-naive patients with HBeAg-negative CHB were randomized to receive ETV 0.5 mg/day or LAM 100 mg/day during the 96 week double-blind phase, followed by open-label treatment through week 240. The primary endpoint was the proportion of patients with virologic response (VR; hepatitis B virus [HBV] DNA<300 copies/mL) at week 24. Secondary objectives included alanine aminotransferase (ALT) normalization and emergence of ETV resistance (week 96), VR and log reduction in HBV DNA levels (week 240), and safety evaluation. RESULTS: In total, 120 patients (>16 years old) were included (ETV, n=56; LAM, n=64). Baseline characteristics were comparable between the two groups. A significantly higher proportion of ETV-treated patients achieved VR compared to LAM at week 24 (92.9% vs. 67.2%, P=0.0006), week 96 (94.6% vs. 48.4%, P < 0.0001), and week 240 (95.0% vs. 47.6%, P < 0.0001). At week 96, ALT normalization was observed in 87.5% and 51.6% of ETV and LAM patients, respectively (P < 0.0001). Virologic breakthrough occurred in one patient (1.8%) receiving ETV and 26 patients (42.6%) receiving LAM (P < 0.0001) up to week 96. Emergence of resistance to ETV was not detected. The incidence of serious adverse events was low and unrelated to the study medications. CONCLUSIONS: Long-term ETV treatment was superior to LAM, with a significantly higher proportion of patients achieving VR. Both treatments were well tolerated.
Alanine Transaminase ; DNA ; Hepatitis B virus ; Hepatitis B* ; Hepatitis B, Chronic* ; Hepatitis* ; Hepatitis, Chronic* ; Humans ; Incidence ; Lamivudine*