Abstract
BACKGROUND: Entecavir (ETV) and tenofovir disoproxil fumarate (TDF) are the two first-line anti-viral therapies for chronic hepatitis B (CHB); however, there are limited studies directly comparing their effectiveness. AIM: To compare the effectiveness of ETV and TDF in nucleos(t)ide-naïve CHB patients with high hepatitis B virus (HBV) DNA levels, defined as serum HBV DNA greater than 6 log10 IU/mL. METHODS: We performed a retrospective multicentre cohort study of adult CHB patients who were seen between 2009 and 2012 at four Northern California community gastroenterology and hepatology clinics. RESULTS: We identified 59 consecutive patients treated with TDF and 216 patients treated with ETV. Pre-treatment characteristics were similar between the two groups. Among HBeAg-negative patients, there was no significant difference in viral suppression rates between ETV and TDF (P = 0.72). In contrast, among HBeAg-positive patients, those treated with TDF achieved viral suppression significantly more rapidly than those treated with ETV (P < 0.0001); the Kaplan-Meier estimated probability of complete suppression was 18% vs. 11% at 6 months, 51% vs. 28% at 12 months and 72% vs. 39% at 18 months respectively. Multivariate Cox proportional hazards analysis indicated that treatment with TDF compared to ETV was a significant predictor of viral suppression, but only for HBeAg-positive patients (HR = 2.59; 95% CI 1.58-4.22; P < 0.001). CONCLUSION: Tenofovir is significantly more effective than entecavir for achieving complete viral suppression in HBeAg-positive, nucleos(t)ide-naïve chronic hepatitis B patients with HBV DNA greater than 6 log10 IU/mL.