This study is a real-world case-control study conducted, with 120 CHB patients who received continuous treatment with PEG-IFN-α for more than 24 weeks as study subjects. Among them, the clinical cure group obtained through PEG-IFN-α treatment is the case group; The group that did not achieve clinical cure after PEG-IFN-α treatment was used as the control group, and the case group and control group were allocated cases in a 2:1 ratio. Collect blood samples from subjects as sequencing samples for candidate genes, use high-throughput sequencing technology to detect the whole genome of subjects, identify relevant genetic polymorphism that have predictive value for clinical cure of chronic hepatitis B treated with PEG-IFN-α, and establish a predictive model and calculation formula between gene polymorphism and the efficacy of PEG-IFN-α antiviral therapy.

This study is a real-world case-control study conducted on 120 patients with chronic hepatitis B (CHB) who were continuously treated with pegylated interferon-α (PEG-IFN-α) for more than 24 weeks. Among them, the clinical cure group obtained through PEG-IFN-α treatment is the case group; The group that did not achieve clinical cure after PEG-IFN-α treatment was used as the control group, and the case group and control group were allocated cases in a 2:1 ratio. Collect blood samples as candidate gene sequencing samples, use high-throughput sequencing technology to detect the whole genome of the subjects, identify relevant genetic polymorphism that have predictive value for clinical cure of chronic hepatitis B with PEG-IFN-α therapy, and establish a predictive model and calculation formula between gene polymorphism and the efficacy of PEG-IFN-α antiviral therapy.

Inclusion Criteria:

• 18 years old ≤ age ≤ 70 years old, Han ethnicity, gender not limited;
• According to the "Guidelines for the Prevention and Treatment of Chronic Hepatitis B (2022)", patients with HBsAg and/or HBV DNA positivity for more than 6 months and chronic inflammatory liver disease caused by persistent HBV infection are diagnosed with chronic hepatitis B (CHB);
• The patient receives subcutaneous injections of PEG-IFN-α for at least 24 consecutive weeks;
• Patients voluntarily sign an informed consent form before the start of the study.

Exclusion Criteria:

• Patients with co infection of HCV, HDV, HIV, and Treponema pallidum;
• Patients with evidence of alcohol abuse, decompensated cirrhosis, liver tumors (liver cancer or AFP>100 ng/ml), or autoimmune diseases.
• Patients who become pregnant during PEG-IFN - α treatment;
• Other situations that the patient deems unsuitable for inclusion in this trial.

Collect blood samples from CHB patients who have completed PEG-IFN - α continuous treatment for more than 24 weeks (two groups of CHB patients who have obtained and have not obtained clinical cure after PEG-IFN - α treatment), to provide samples for sequencing candidate genes.