Immunogenicity and Safety of SYS6017 in the Participants Aged 40 Years and Above

Inclusion Criteria: * 1\. Individuals aged 40 years or older; * 2\. Able to understand the study procedures, comply with the protocol requirements to attend all the scheduled visits, voluntarily consent to participate in the study, and sign the informed consent form; * 3\. Is physically eligible at the discretion of investigators based on medical history inquiry and physical examination; For participants with chronic underlying diseases (e.g., diabetes mellitus, hypertension, hyperlipidemia and other chronic conditions), they may be enrolled if their conditions have been well controlled within 3 months prior to enrollment in this study (i.e., additional medical interventions or major adjustments to treatments are not required); * 4\. For female participants of childbearing potential: No sexual activity or effective contraceptive methods were used within one menstrual cycle before enrollment; No pregnancy plans and agree to adopt effective contraceptive methods within 8 months after enrollment. Exclusion Criteria: * 1\. History of zoster; * 2\. History of vaccination with varicella vaccine or zoster vaccine (including investigational vaccine); * 3\. Axillary temperature ≥ 37.1℃ on the day of enrollment or within 24 h before enrollment; * 4\. History of allergy to any component of the investigational vaccine; or history of severe allergic reactions to vaccines or medications (including but not limited to anaphylaxis, allergic laryngeal edema, Henoch-Schönlein purpura, thrombocytopenic purpura, or Arthus reaction); * 5\. History of myocarditis, pericarditis, or idiopathic cardiomyopathy, or any condition that could increases the risk of myocarditis or pericarditis * 6\. History of demyelinating diseases, including but not limited to Guillain-Barré syndrome, multiple sclerosis, ophthalmoneuromyelitis, acute disseminated encephalomyelitis, etc.; * 7\. Current epilepsy or convulsion, severe neurological or psychiatric disorders; * 8\. Have contraindications to intramuscular injection, e.g., diagnosed thrombocytopenia, any coagulation disorders, or ongoing treatment with anticoagulants, etc.; * 9\. Active malignant tumor, malignant tumor without adequate treatment, malignant tumor with a potential risk of recurrence during the study; * 10\. Active, unstable, severe or uncontrolled cardiovascular and cerebrovascular diseases, thrombotic diseases, blood and lymphatic system diseases, liver and kidney diseases, respiratory diseases, metabolic diseases, musculoskeletal diseases, autoimmune diseases, etc; * 11\. History of diagnosed immunocompromise or immunosuppression, congenital or functional asplenia, or splenectomy before enrollment; * 12\. Long-term (defined as more than 14 consecutive days) systemic use of immunosuppressants, immunostimulants, or other immunomodulatory drugs (e.g., corticosteroids at a dose of ≥ 20 mg/day prednisone or equivalent) within 6 months prior to enrollment; however, inhaled and topical corticosteroids are permitted; or planned administration of the aforementioned agents during the study period; * 13\. Administration of whole blood, plasma, serum, immunoglobulin, or monoclonal antibodies within 3 months prior to enrollment, or planned administration of the aforementioned products during the study period; * 14\. Blood donation or blood loss ≥ 450 mL within one month before enrollment, or planning to donate blood during the study; * 15\. Vaccination with any other vaccines within 30 days prior to enrollment, or planned vaccination with any other vaccines within 30 days after the last dose of the study vaccine; * 16\. Current participation in or planned participation in other clinical trials during the study period; * 17\. For female participants of childbearing potential: positive pregnancy test result prior to enrollment, current pregnancy or lactation, or planned pregnancy within 8 months after enrollment; * 18\. Unable to comply with the study procedures and requirements, or presence of other conditions that make the participant inappropriate for this clinical trial, as judged by the investigators.