lot-to-lot consistency of quadrivalent influenza vaccine (split virion), inactivated

Conditions: Seasonal Influenza

Summary: this study is a randomized, double-blind phase ⅳ clinical trial of quadrivalent influenza vaccine (split virion), inactivated manufactured by sinovac biotech co., ltd.the purpose of this study is to evaluate the lot-to-lot consistency, immunogenicity and safety of quadrivalent influenza vaccine (split virion), inactivated in health subjects aged 9-59 years old.

this study is a randomized, double-blind phase ⅳ clinical trial in health subjects aged 9-59 years old to evaluate the lot-to-lot consistency,immunogenicity and safety of quadrivalent influenza vaccine (split virion), inactivated.the experimental vaccine was manufactured by sinovac biotech co., ltd.a total of 1260 subjects,including 360 subjects aged 9-17 years and 900 subjects aged 18-59 years will be enrolled.the subjects in each age group will be randomly divided into three groups in a ratio of 1:1:1 to receive one dose of three lots of quadrivalent influenza vaccine (split virion), inactivated produced on a commercial scale,respectively.

Eligibility criteria:
inclusion criteria: * healthy subjects aged 9-59 years; * the subjects and/or guardians can understand and voluntarily sign the informed consent form (for subjects aged 9-17 years, both subjects and guardians need to sign the informed consent form). * proven legal identity. exclusion criteria: * received seasonal influenza vaccine for 2022-2023 influenza season, or had an influenza vaccine schedule during the study; * suffering from seasonal influenza in the past 6 moths; * women of childbearing age (menarche to premenopause) are pregnant(including positive urine pregnancy test), breastfeeding or planning pregnancy within 1 month; * patients with fever on the day of vaccination,underarm body temperature\>37.2 ℃; * history of asthma, allergy to vaccines or vaccine components, and serious adverse reactions to vaccines, such as urticaria, dyspnea, and angioneurotic edema; * congenital malformations or developmental disorders, genetic defects, severe malnutrition, etc. * 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; * thyroid disease or history of thyroidectomy,absence of spleen, functional functional asplenia,and absence of spleen or splenectomy as a result of any condition; * 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; * onset of various acute or chronic diseases within 7 days prior to the study; * 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; * the subjects participated in other clinical trials during the follow-up period or will be planned to participate other clinical trials during the follow-up period; * according to the investigator's judgment, the subject has any other factors that are not suitable for participating in the clinical trial.