Disclosures: The following people have nothing to disclose: Fen Liu, Fang Wei, Xiwei Wang, Huaidong Hu, Peng Hu, Dazhi Zhang, Hong Ren Background: It has been one of unsolved issues and unmet needs in chronic

hepatitis B (CHB) treatment to manage multi-drug resistant (MDR) hepatitis B virus. The aim of this study was to elucidate the antiviral efficacy and safety of entecavir plus tenofovir combination therapy in patients with MDR CHB. Methods: In this prospective ongoing multicenter study, patients with MDR CHB defined as detectable HBV DNA (> 60 IU/mL) while on any rescue treatment regimen for at least 24 weeks and prior experience of genotypic resistance to both nucleoside HDAC inhibitor analogue(s) and nucleotide analogue are treated with entecavir and tenofovir combination therapy. The primary endpoint is the proportion of patients Buparlisib manufacturer with HBV DNA < 60 IU/ml at Week 48. We present here the first 12 week interim analysis. Results: 61 patients were enrolled at the time interim analysis and 42 of these reached week 12. At baseline, mean age was 47.4 years, 83% were male, 86% were HBeAg(+), mean HBV DNA was 4.55 (±1.23) log 10IU/ml, and

mean ALT was 41.3 IU/ml; 4 patients (9.5%) had documented resistance mutations to lamivudine (LAM) only, 3 (7.1%) to LAM and adefovir (ADF), 14 (33.3%) to ADF, 4 (9.5%) to LAM and entecavir, and 8 (19.0%) to all. By week 4, 9 (21.4%) patients achieved HBV DNA < 60 IU/ml and the mean reductions in HBV DNA was 1.39 ± 0.77 log 10IU/ml. By week 12, 24 (57.1%) patients achieved HBV DNA < 60 IU/ml and the mean reductions in HBV DNA was 2.11 ± 0.77 log 10IU/ml. On-treatment ALT flare was reported in 1 patient during the first 12 week. There was no serious adverse event. Conclusions: In the first 12 week interim analysis in patients with MDR CHB, entecavir plus tenofovir combination therapy early suppressed HBV replication to undetectable HBV DNA levels in the majority (57.1%) of patients.

Disclosures: Chang Wook Kim – Consulting: Gilead; Grant/Research Support: BMS, Boehringer Ingelheim, Pharmicell; Speaking and Teaching: BMS, GSK, Dae-woong The following L-gulonolactone oxidase people have nothing to disclose: Jun Yong Park, Si Hyun Bae, Sang Hoon Ahn Background: ETV is one of the most effective antiviral drugs for the treatment of chronic hepatitis B (CHB). Some patients, however, will have suboptimal response to ETV; and there are limited data in how to proceed with alternative treatment. Methods: This is a retrospective cohort study of 51 consecutive adult patients with CHB who, as ETV partial responders (detectable HBV DNA levels >60 IU/mL after ≧12 months of ETV), were switched to either TDF monotherapy or TDF+ETV combination therapy at four U.S. liver/gastroenterology clinics.