Lot-to-lot Consistency of 23-valent Pneumococcal Polysaccharide Vaccine

This study is a randomized, double-blind phase Ⅳ clinical trial of 23-valent pneumococcal polysaccharide vaccine manufactured by Sinovac Biotech Co., Ltd.The purpose of this study is to evaluate the consistency of three consecutive lots, immunogenicity and safety of 23-valent pneumococcal polysaccharide vaccine of commercial scale in participants aged 40-65 years.

Inclusion Criteria:Adults aged 40-65 years in stable health;The subjects can understand and voluntarily sign the informed consent form;Proven legal identity.Exclusion Criteria:Have received any pneumococcal vaccine;History bacterial pneumonia or invasive pneumococcal infectious diseases caused by pneumococci and confirmed by culture;Women of childbearing age (menarche to premenopause) are pregnant (including positive urine pregnancy test), breastfeeding or planning pregnancy within 1 month;History of asthma, allergy to vaccines or vaccine components, and serious adverse reactions to vaccines, such as urticaria, dyspnea, and angioneurotic edema;Severe chronic diseases,such as severe cardiovascular diseases, hypertension(Systolic blood pressure ≥140mmHg and/or diastolic blood pressure ≥90mmHg) and diabetes that cannot be controlled by drugs, liver or kidney diseases,malignant tumors, etc.;Severe neurological disease (epilepsy, convulsions or convulsions) or mental illness;Autoimmune disease or immune deficiency/immunosuppression;Diagnosed abnormal blood coagulation function (eg, lack of blood coagulation factors, blood coagulopathy, abnormal platelets) or obvious bruising or blood coagulation;Immunosuppressive therapy, cytotoxic therapy, inhaled corticosteroids(excluding allergic rhinitis corticosteroid spray therapy, acute noncomplicated dermatitis superficial corticosteroid therapy) in the past 6 months;A long history of alcohol or drug abuse;Receipt of blood products within in the past 3 months;Receipt of other investigational drugs within 30 days prior to receiving the investigational vaccine;Receipt of attenuated live vaccines or COVID-19 vaccines in the past 14 days;Receipt of inactivated or subunit vaccines in the past 7 days;Onset of various acute or chronic diseases within 7 days prior to the study;Underarm body temperature before vaccination>37.0°C;The subjects participated in other clinical trials during the follow-up period or will be planned to participate other clinical trials within 1 months;According to the investigator's judgment, the subject has any other factors that are not suitable for participating in the clinical trial.