A Single-center, Randomized, Double-blind Clinical Trial to Evaluate the Safety and Batch Consistency of the EV71 Vaccine in Infants Aged 6 to 35 Months After Vaccination According to a Two-dose Immunization Schedule
试验速览
- 阶段
- 4 期
- 状态
- 已完成
- 入组人数
- 720
- 试验地点
- 1
- 主要终点
- The GMT of EV71 neutralizing antibodies 30 days after complete immunization with the EV71 vaccine
研究概览
简要总结
This trial is designed as a single-center, randomized, double-blind study. A total of 720 infants aged 6 to 35 months are selected (with 240 subjects in each age group: 6-11 months, 12-23 months, and 24-35 months). Subjects from different age groups are randomly allocated to three batch groups in a 1:1:1 ratio, and receive two doses of the EV71 vaccine from the commercial production batch on days 0 and 30. After each vaccination dose, subjects will be observed for immediate reactions for 30 minutes and for solicited adverse events for the next 7 days, as well as for unsolicited adverse events over the 30 days following vaccination. All subjects will have blood samples collected on day 0 (pre-immunization) and day 60 for serum antibody testing. Additionally, 270 subjects will be selected, for additional blood sampling at various time points: 7 days, 14 days, and 30 days after the first dose, and 7 days and 14 days after the second dose, to assess the EV71 antibody levels at different timepoints following various doses of vaccination.
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Parallel
- 主要目的
- Prevention
- 盲法
- Double (Participant, Investigator)
入排标准
- 年龄范围
- 6 Months 至 35 Months（Child）
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- •Infants and young children aged 6 to 35 months.
- •Able to provide legal identification.
- •The guardian of the subject has the ability to understand and agrees to sign the informed consent form.
排除标准
- •Previous vaccination with the EV71 vaccine.
- •History of hand, foot, and mouth disease.
- •History of allergies, asthma, including allergies to vaccines or vaccine components, and severe adverse reactions to vaccines, such as urticaria, difficulty breathing, angioedema, or abdominal pain.
- •Congenital malformations or developmental disorders, genetic defects, severe malnutrition, etc.
- •Autoimmune diseases or immune deficiencies/immunosuppression.
- •Severe neurological disorders (epilepsy, convulsions, or seizures) or mental illness.
- •History of thyroidectomy, asplenia, functional asplenia, or any condition leading to asplenia or splenectomy.
- •Blood coagulation abnormalities diagnosed by a physician (such as clotting factor deficiencies, coagulopathies, platelet abnormalities) or evident bruising or bleeding disorders.
- •Treatment with immunosuppressants, cytotoxic therapy, or inhaled corticosteroids within 6 months prior to enrollment (excluding corticosteroid nasal spray therapy for allergic rhinitis, or topical corticosteroid treatment for acute non-complicated dermatitis).
- •Receipt of blood products within 3 months prior to vaccination with the trial vaccine.
- •Receipt of other investigational vaccines within 30 days prior to vaccination with the trial vaccine.
- •Receipt of live attenuated vaccines within 14 days prior to vaccination with the trial vaccine.
- •Receipt of subunit or inactivated vaccines within 7 days prior to vaccination with the trial vaccine.
- •Any acute illness or acute exacerbation of chronic illness within the past 7 days.
- •Fever before receiving the investigational vaccine, with an axillary temperature > 37.0°C.
- •Any other factors that, in the investigator's judgment, make the subject unsuitable for participation in the clinical trial.
研究组 & 干预措施
Batch group 1
EV71 vaccine first commercial production batch
干预措施: EV71 Vaccine (Biological)
Batch group 2
EV71 vaccine second commercial production batch
干预措施: EV71 Vaccine (Biological)
Batch group 3
EV71 vaccine third commercial production batch
干预措施: EV71 Vaccine (Biological)
结局指标
主要结局
The GMT of EV71 neutralizing antibodies 30 days after complete immunization with the EV71 vaccine
时间窗: 30 days after second dose
次要结局
- The incidence of serious adverse events during the safety observation period(30 days after the second dose)
- Seroconversion rates, seropositive rates, and GMT of antibodies at 7 days, 14 days, and 30 days after the first dose of the EV71 vaccine(7,14 and 30 days after the first dose)
- Seroconversion rates, seropositive rates, and GMT of antibodies at 7 days and 14 days after the second dose of the EV71 vaccine, as well as the seroconversion rate and seropositive rate at 30 days post-vaccination(7,14 and 30 days after the second dose)
- The incidence of adverse reactions within 30 days after each dose of the EV71 vaccine(30 days after each dose)
- The incidence of solicited adverse events within 0-7 days after each dose of the EV71 vaccine(7 days after each dose)