This study is divided into two parts. Part A is a multicenter, randomized, double-blind, placebo controlled phase Ill clinical trial, designed to evaluate the efficacy and safety of ZM-H1505R in combination with NAs versus NAs monotherapy with HBV DNA ≥ 50 IU/mL and are HBeAg positive who have received NAs monotherapy for at least 12months.Part B is an open-label extension and follow-up period designed to evaluate the long-term safety and efficacy of ZM-H1505R in combination with NAs.
1.Able to understand and sign the written informed consent form;
2.Adult males and females aged 18-65 years(inclusive) at screening;
3.Have been used NAs monotherapy with ETV(0.5 mg or 1.0mg, QD),TDF (300 mg, QD),TAF (25 mg, QD),or TMF (25 mg, OD)for at least 12 months at the time of enrollment; Have been on stable and continuous use of one of these medications for at least 6months, and do not plan to switch to any other NAs class of medications after entering this clinical trial;
4.Evidence of prior HBV infection (e.g., HBsAg and/or HBV DNA positive), or HBsAg positive at screening;
1.Progressive fibrosis or cirrhosis detected at screening, or progressive fibrosis or cirrhosis defined as follows: Metavir ≥ 3 or Ishak fibrosis score ≥ 4 by liver biopsy within 1 year prior to screening; or in the absence of an appropriate liver biopsy, liver stiffness test (FibroScan) ≥ 9 kPa within 3 months prior to screening, or liver stiffness test (FibroTouch) ≥ 9.6 kPa(FibroScan preferred) ;
2.History of hepatocellular carcinoma (HCC); or serum alpha-fetoprotein (AFP) ≥ 50 ng/mL at screening, or imaging examination such as abdominal ultrasound, CT (computed tomography) or MRI (magnetic resonance imaging) suggesting possible HCC;
Hemoglobin < 110 g/L (for males) or < 100 g/L (for females);
Platelet count < 90 × 109/L;