The objective of this study was to evaluate the safety, immunogenicity and immune persistence of recombinant herpes zoster vaccine (CHO cells) with different adjuvant doses in healthy people aged 40 years and older.

Inclusion Criteria:

• Male or female participants aged 40 years or older at the time of enrollment.
• Voluntarily agrees to participate in the trial, fully understands, and signs the informed consent form.
• Able to attend all scheduled follow-ups and comply with the clinical trial protocol requirements to complete the trial.
• Female participants must meet the following criteria:1)Surgically sterilized or postmenopausal for ≥2 years, or women of childbearing potential (not menopausal or menopausal <2 years) with a negative pregnancy test and willing to use effective physical contraception (e.g., condoms, intrauterine device) from enrollment until 6 months after full immunization. 2)Agree not to breastfeed from enrollment until 6 months after full immunization.
• Axillary temperature ≤37.0°C.

Exclusion Criteria:

a Exclusion criteria for the first dose:

• A history of herpes zoster.
• A history of varicella or herpes zoster vaccination.
• Close contact with a varicella/herpes zoster patient within the past year.
• Received immunoglobulin and/or any blood products within 3 months before vaccination.
• Received immunosuppressive treatment within 3 months prior to vaccination (e.g., systemic corticosteroids for ≥14 days, at a dose ≥2 mg/kg/day or ≥20 mg/day of prednisone, or an equivalent dose of prednisone) (excluding inhaled, intra-articular, and topical steroids).
• A history of severe allergic reactions to any vaccine or medication (e.g., anaphylactic shock, allergic laryngeal edema, allergic purpura, thrombocytopenic purpura, local allergic necrosis reactions, severe urticaria, etc.), or a family history of severe allergies.
• Immunocompromised or diagnosed with congenital or acquired immune deficiency diseases, or infected with Human Immunodeficiency Virus (HIV).
• A history of seizures, epilepsy, encephalopathy (such as congenital brain malformation, brain trauma, brain tumors, cerebral hemorrhage, cerebral infarction [except for infarction without sequelae or lacunar infarction], brain infections, or brain damage caused by chemical drug poisoning), or psychiatric disorders, or a family history of psychiatric disorders; or other serious neurological diseases.
• Inadequate time interval between vaccination and other vaccines (e.g., inactivated or recombinant subunit vaccines within 14 days prior to vaccination, live attenuated vaccines, viral vector vaccines, or mRNA vaccines within 28 days prior to vaccination).
• Acute illness or an acute exacerbation of a chronic disease within 3 days prior to vaccination, or use of antipyretic, analgesic, or antihistamine medications within 3 days prior to vaccination.
• Suffering from severe infectious skin diseases.
• Ongoing or long-term alcohol and/or drug abuse history (Note: for the past three months, males drinking more than 14 standard drinks per week, females more than 7 standard drinks per week. One standard drink contains 14g of alcohol, equivalent to 360mL of beer, 45mL of liquor at 40% alcohol, or 150mL of wine. Drug abuse refers to the repeated or excessive use of drugs with dependence potential unrelated to recognized medical needs, for non-medical purposes).
• A history of thrombocytopenia or other coagulation disorders that may contraindicate intramuscular injection.
• Severe liver or kidney disease, complications from diabetes, severe cardiovascular diseases, or uncontrolled hypertension despite medication.
• Asplenia or functional asplenia, or any condition leading to splenectomy.
• Abnormal laboratory test results before the first dose, deemed clinically significant by the investigator (only applicable to Phase I).
• Currently participating in other experimental or unregistered clinical trials for products (drugs, vaccines, or devices), or planning to participate in another clinical trial before the end of this trial.
• A history of hematologic or lymphatic system diseases, such as unexplained lymphadenopathy or hematolymphatic lymphoma.
• A history of diagnosed potential immune-mediated diseases, autoimmune diseases, or Guillain-Barré syndrome.
• Any other condition deemed by the investigator to be unsuitable for participation in this clinical trial.

a Exclusion criteria for the second dose:

• Positive urine pregnancy test.
• Grade 4 adverse events related to vaccination.
• Severe allergic reactions occurring after vaccination.
• New findings or newly occurring conditions that meet the exclusion criteria after the first dose, with the investigator determining whether to terminate the trial vaccine administration.
• Other situations assessed by the investigator as requiring termination of vaccination.