Inclusion Criteria:
* 1\. Subjects voluntarily sign the informed consent, fully understand the study content, and are willing and able to comply with all trial procedures.
* 2\. Male or female, aged 18 to 65 years.
* 3\. Has a clinical diagnosis of chronic hepatitis B virus infection based on protocol-defined criteria.
* 4\. Is receiving stable antiviral treatment with a single nucleos(t)ide analogue before enrollment. Has adequately suppressed HBV DNA and acceptable liver function based on protocol-defined criteria before the first administration of adjuvant or TVAX-028.
* 5\. Has HBeAg-negative chronic hepatitis B virus infection based on protocol-defined criteria.
* 6\. Has hepatitis B surface antigen (HBsAg) levels within the protocol-defined range before the first administration of adjuvant or TVAX-028.
* 7\. Has no evidence of autoimmune liver disease based on protocol-defined testing and investigator assessment.
* 8\. Participants of childbearing potential must agree to use effective contraception for the protocol-defined period.
Exclusion Criteria:
* 1\. Has liver disease other than chronic hepatitis B virus infection that may interfere with study participation or interpretation of study results
* 2\. Has evidence or suspected evidence of hepatocellular carcinoma, cirrhosis, clinically significant hepatic space-occupying lesions, or clinically significant liver fibrosis based on imaging, laboratory testing, or non-invasive liver assessment.
* 3\. Has clinically significant abnormalities in laboratory tests, including but not limited to liver function, renal function, hematology, coagulation, or electrolyte parameters, based on protocol-defined criteria.
* 4\. Has received interferon or pegylated interferon treatment within the protocol-defined period before the first administration of adjuvant or TVAX-028, or plans to receive such treatment during the study.
* 5\. Has received immunosuppressive therapy within the protocol-defined period before the first administration of adjuvant or TVAX-028.
* 6\. Has received corticosteroid therapy within the protocol-defined period before the first administration of adjuvant or TVAX-028, except for permitted topical or inhaled corticosteroids.
* 7\. Has clinically significant cardiovascular, renal, pancreatic, or other systemic disease that may increase study risk or interfere with study assessments.
* 8\. Has inadequately controlled diabetes mellitus or hypertension based on protocol-defined criteria.
* 9\. Has evidence of clinically significant co-infection, including hepatitis C virus, hepatitis D virus, human immunodeficiency virus, or active syphilis infection.
* 10\. Has a history of malignancy within the protocol-defined period before the first administration of adjuvant or TVAX-028, except for conditions permitted by the protocol.
* 11\. Has previously received organ transplantation.
* 12\. Has a history of severe drug and food allergy, or is known to be allergic to any component of the investigational product or related products.
* 13\. Has a history of drug abuse or clinically significant alcohol abuse within the protocol-defined period before the first dose.
* 14\. Has a history or current diagnosis of psychiatric disease, severe depression, or other condition that may affect compliance with study procedures.
* 15\. Has a history of severe allergy, or is known or suspected to be allergic to any component of the investigational product, adjuvant, or related products.
* 16\. Has participated in another clinical trial of an investigational drug, biologic, medical device, or vaccine within the protocol-defined period before the first administration of adjuvant or TVAX-028.
* 17\. Is pregnant or breastfeeding.
* 18\. Is considered by the investigator to be unsuitable for participation in this study for any other reason.
