A Study to Evaluate the Antiviral Activity and Safety of HH-003 Injection in Subjects With HBeAg-Negative Chronic Hepatitis B Treated With Nucleos(t)Ide Reverse Transcriptase Inhibitors

A Multicenter, Randomized, Controlled Phase IIa Study to Evaluate the Antiviral Activity and Safety of HH-003 Injection in Subjects With HBeAg-Negative Chronic Hepatitis B Treated With Nucleos(t)Ide Reverse Transcriptase Inhibitors

This is a multicenter, randomized, controlled Phase IIa study of HH-003 injection, HH-003 injection is a monoclonal antibody targeting Hepatitis B virus. This study aims to evaluate the antiviral activity and safety in subjects with with HBeAg-negative Chronic Hepatitis B treated with nucleos(t)ide reverse transcriptase inhibitors.

Inclusion Criteria:

• Signed informed consent form;
• Male or female aged from 18 to 65years (inclusively);
• 18 kg/m^2≤BMI≤32 kg/m^2, body weight≥45 kg for men and ≥40 kg for women;
• At screening, etiological, clinical, or pathological evidence indicates chronic hepatitis B virus infection for at least 6 months; and negative HBeAg for more than 6 months; 10 IU/mL≤HBsAg≤3000 IU/mL; HBV DNA≤20 IU/mL; ALT≤1×ULN;
• Participants who have been on the treatment of nucleos(t)ide reverse transcriptase inhibitors (limited to entecavir [ETV], tenofovir disoproxil fumarate [TDF], or tenofovir alafenamide fumarate [TAF]) for at least 3 years (as judged by the investigator) at screening.

Exclusion Criteria:

• Females who are pregnant or lactating at screening;
• History of alcoholic liver disease, non-alcoholic steatohepatitis, autoimmune liver disease, other hereditary liver disease, drug-induced liver disease or other clinically significant chronic liver disease induced by non-HBV infection;
• History or presence of progressive liver fibrosis or cirrhosis, including but not limited to liver stiffness measurement [LSM] ≥ 9 kPa at screening, progressive liver fibrosis or cirrhosis (e.g., S ≥ 3 in GS score or METAVIR ≥ F3) by liver histopathology examination, according to the Consensus on the diagnosis and therapy of hepatic fibrosis [2019]; or the presence of ascites, hepatic encephalopathy, upper gastrointestinal bleeding, or esophageal and gastric varices.
• History or presence of hepatocellular carcinoma, or alpha-fetoprotein (AFP) ≥ 50 ng/mL at screening; or suspicion of hepatocellular carcinoma indicated by liver ultrasound, CT, or MRI.
• Use of antiviral therapy with interferon within 1 year prior to screening
• Any of the following lab test results at screening: total bilirubin >2xULN or direct bilirubin >1.5xULN, hemoglobin <120 g/L for males or <110 g/L ro females, platelets count<100,000/mm^3 (100×10^9/L), and absolute neutrophils count <1,500/mm^3 (1.5×10^9/L), Serum albumin < 35 g/L; international normalized ratio (INR) of prothrombin time > 1.3; or estimated glomerular filtration rate (eGFR) < 60 mL/min/1.73 m2.