Virologic, serologic, and biochemical outcomes through 2 years of treatment with entecavir and lamivudine in nucleoside-naïve Chinese patients with chronic hepatitis B: a randomized, multicenter study

PURPOSE Entecavir demonstrated superior virologic and biochemical benefits over lamivudine at 48 weeks in nucleoside-naïve Chinese patients with chronic hepatitis B (CHB). We evaluated the effect of continued entecavir and lamivudine treatment in patients who continued treatment in year 2 and the off-treatment durability of patients who achieved a protocol-defined consolidated response at week 48. METHODS Chinese adults (n = 519) with CHB were randomized to a minimum of 52 weeks of treatment with entecavir 0.5 mg/day or lamivudine 100 mg/day. Patients with a consolidated response at week 48 (HBV DNA <0.7 MEq/ml for >/=24 weeks, ALT <1.25 times ULN, and, if HBeAg(+) at baseline, loss of HBeAg for at least 24 weeks) stopped treatment at week 52 and were followed off-treatment. Patients with a partial response at week 48 (HBV DNA <0.7 MEq/ml in the absence of other criteria for a consolidated response) could continue blinded treatment for up to 96 weeks. Patients were assessed for HBV DNA, ALT normalization, safety, and, if HBeAg(+) at baseline, for HBe seroconversion. Cumulative proportions of all treated patients who ever achieved these responses were also analyzed. RESULTS Among patients treated during year 2 (entecavir: n = 193; lamivudine: n = 145), 74% of entecavir-treated and 41% of lamivudine-treated patients had HBV DNA <300 copies/ml by PCR at end of dosing and 96% of entecavir-treated and 82% of lamivudine-treated patients normalized ALT. Eleven percent of entecavir-treated versus 19% of lamivudine-treated patients underwent HBe seroconversion during year 2. Cumulative confirmed analysis for all treated patients through 96 weeks showed that 79% of entecavir-treated versus 46% of lamivudine-treated patients (p < 0.0001) achieved HBV DNA <300 copies/ml by PCR. Similar proportions of entecavir- and lamivudine-treated patients achieved confirmed ALT normalization and HBe seroconversion. Safety profile was comparable for both treatment groups. CONCLUSIONS Through 96 weeks of treatment, entecavir resulted in continued clinical benefit in nucleoside-naïve Chinese patients with CHB, with a safety profile comparable with lamivudine.