Background and aims: In patients with chronic hepatitis B (CHB) who have failed on other nucleos(t)ide analogs (NUCs), the combination of entecavir (ETV) plus tenofovir disoproxil fumarate (TDF), two potent agents with non-overlapping resistance profiles, may provide a single rescue regimen. Methods: In this single-arm, open-label study, 92 CHB patients with a primary non-response, partial response, or virologic breakthrough on their current NUC were switched to ETV (1 mg) plus TDF (300 mg) and treated for 96 weeks. Results: At baseline, 62 % of patients were HBeAg(+) and mean HBV DNA was 4.4 log10IU/mL. Patients had received ≥1 line of prior NUC therapy, with the latest regimen consisting of monotherapy with ETV (53 %), lamivudine (LVD 22 %), TDF (12 %), adefovir (ADV 4 %), or telbivudine (2 %), or combinations of these agents (7 %); 58 % had evidence of single- or multidrug resistance mutations (LVD 52 %, ETV 26 %; ADV 7 %). Response rates for HBV DNA <50 IU/mL were 76 % (70/92) at week 48 (primary endpoint), and 85 % (78/92) at week 96, including 80 % (16/20) in prior LVD failures, 100 % (4/4) in ADV failures, 82 % (9/11) in TDF failures, and 88 % (42/48) in ETV failures. No treatment-emergent resistance to ETV or ADV was observed. ETV/TDF was well tolerated, with no significant renal or additive toxicities observed. Conclusions: In NUC-experienced patients who have failed prior NUC therapy, ETV/TDF was well tolerated and effective, achieving virologic suppression through 96 weeks in the majority (85 %), irrespective of prior NUC exposure, without occurrence of treatment-emergent resistance to either agent.

Additional Metadata
Keywords Antiviral resistance, Multidrug failure, Partial response, Primary non-response, Rescue therapy, Virologic breakthrough
Persistent URL dx.doi.org/10.1007/s12072-016-9737-2, hdl.handle.net/1765/92405
Journal Hepatology International
Citation
Zoulim, F, Białkowska-Warzecha, J, Diculescu, M.M, Goldis, A.E, Heyne, R, Mach, T, … Janssen, H.L.A. (2016). Entecavir plus tenofovir combination therapy for chronic hepatitis B in patients with previous nucleos(t)ide treatment failure. Hepatology International, 10(5), 779–788. doi:10.1007/s12072-016-9737-2