A Clinical Study of HH-006 in Untreated Chronic Hepatitis B Virus Infected Patients

This is a randomized, double-blind, placebo-controlled, multiple-dose escalation Phase I clinical study. The study aims to evaluate the safety, tolerability, pharmacokinetic profile, and preliminary antiviral activity of multiple doses (120 mg QW, 240 mg QW, 480 mg QW, administered subcutaneously (S.C.) once weekly (QW) for 5 doses) in chronic hepatitis B virus (HBV) infected participants who are not receiving anti-HBV treatment, are HBeAg-negative or positive, have HBV DNA ≥ 100 IU/mL, 100 IU/mL \< HBsAg \< 5000 IU/mL, and ALT ≤ 5 × ULN.

Each dose cohort plans to enroll 12 participants, enrolled in batches according to the dose escalation principle. Participants will be randomized to receive either HH-006 (N=9) or placebo (N=3) for a repeated-dose (5 doses) tolerability and pharmacokinetic study.

Dosing for the next cohort will commence only after all 12 participants in the current dose cohort have completed the safety assessment up to 14 days post-last dose (Week 7, Day 43) and after review and approval by the Safety Review Committee. The currently planned maximum dose for escalation is 480 mg QW.

Each participant is planned to be followed up for 24 weeks after the last dose to assess the safety, tolerability, PK, immunogenicity, and preliminary antiviral activity of HH-006 in participants with chronic HBV infection. During the study, adjustments to the maximum dose, dosing regimen, blood sampling time points, and follow-up duration may be made based on the accumulating data obtained during the study.

Throughout the study, participants' safety indicators and virologic parameters will be closely monitored to evaluate the safety and antiviral activity of HH-006.