Entecavir+tenofovir vs. lamivudine/telbivudine+adefovir in chronic hepatitis B patients with prior suboptimal response

BACKGROUND/AIMS: Suboptimal responses to lamivudine or telbivudine plus adefovir (LAM/LdT+ADV) rescue therapy are common in patients with LAM-resistant hepatitis B virus (HBV) infections. We compared patients switched to entecavir plus tenofovir (ETV+TDF) to those maintained on LAM/LdT+ADV. METHODS: This prospective randomized controlled trial examined 91 patients whose serum HBV DNA levels were greater than 60 IU/mL after at least 24 weeks of treatment with LAM/LdT+ADV for LAM-resistant HBV. Patients were randomized to receive a new treatment (ETV+TDF, n=45) or maintained on the same treatment (LAM/LdT+ADV, n=46) for 48 weeks. Patients with baseline ADV resistance were excluded. RESULTS: Compared to LAM/LdT+ADV group, ETV+TDF group had more patients with a virologic response (42/45 [93.33%] vs. 3/46 [6.52%], P<0.001) and had a greater mean reduction in serum HBV DNA level from baseline (-4.16 vs. -0.37 log(10) IU/mL, P<0.001). Multivariate analysis indicated that high baseline HBV DNA level (P=0.005) and LAM/LdT+ADV maintenance therapy (P=0.001) were negatively associated with virologic response. At week 48, additional ADV- or ETV-associated mutations were cleared in ETV+TDF group, but such mutations were present in 4.3% of patients in LAM/LdT+ADV group (P=0.106). The two groups had similar rates of adverse events. CONCLUSIONS: ETV+TDF combination treatment led to a significantly higher rate of virologic response compared to LAM/LdT+ADV combination treatment in patients with LAM-resistant HBV who had suboptimal responses to LAM/LdT+ADV regardless of HBV genotypic resistance profile (NCT01597934).