Safety & Immunogenicity of Enterovirus Type 71 Vaccine in Healthy Adults and Children 6-71months

General objective:

• To evaluate the safety of EV71 vaccine in adults and in children age 6-71 months
• To evaluate the immunogenicity of the vaccine in children by assessing the neutralization antibody levels before immunization; then 7, 15, 30 days after the first inoculation; and also 7, 15, 30 days after the second inoculation.
• To assess the incidence rate of adverse reactions/events

Specific objective: To find out:

• Seroconversion rate of neutralization antibody on the day 30 after the whole-range immunization (i.e. after 2nd dose of vaccination);
• Positive rate and Geometric Mean Titer of neutralization antibody on the day 30 after the whole-range immunization;
• Seroconversion rate, positive rate and Geometric Mean Titer of serum neutralization antibody on the day 7, day 15, day 30 after the first inoculation;
• Seroconversion rate,positive rate and Geometric Mean Titer of serum neutralization antibody on the day 7, day 15 after the second inoculation;
• The incidence rate of adverse reactions & serious adverse events during the observation period of safety;
• The incidence rate of adverse reactions 0-30 days after each inoculation of vaccine;
• The incidence rate of adverse events 0-7 days after each inoculation of vaccine;

Inclusion criteria

• Bangladeshi healthy adults 18-45yrs and children aged 6-71 months on the day of screening;
• Either sex;
• The participant /parents or guardian of the participant properly informed about the study and having signed the informed consent form (ICF);
• Participant/Parents' or guardian's availability for the entire period of the study and reachability by study staff for post-vaccination follow-up

Exclusion criteria

Exclusion criteria

for Inoculation of the First Dose:

Whether the participant should be enrolled should be judged according to the following criteria. The participant cannot participate in the study if any of the following circumstances exists:

• Previous history of hand, foot and mouth disease;
• Allergy history to vaccine or components of the vaccine, previous history of asthma, serious adverse effects of the vaccine such as urticaria, dyspnea, angioneurotic edema or stomachache, etc;
• Congenital malformation or developmental disorder, genetic defect, serious malnutrition, etc;
• Autoimmune disease or immunodeficiency or immunosuppression;
• Severe neurological disorders (epilepsy, convulsion or tic) or family history of mental disease;
• History of thyroidectomy, or asplenia or functional asplenia;
• Severely malnourished children
• Abnormal coagulation functions (such as coagulation factor deficiency, blood coagulation disease and blood platelet disorders) or obvious bruise or blood coagulation disorders diagnosed by the doctors;
• Received immunosuppressant therapy, cytotoxic drug therapy and inhaled corticosteroid therapy (excluding the corticosteroid aerosol therapy for allergic rhinitis and surface corticosteroid therapy for acute non-complicated dermatitis) in the past 6 months;
• Received blood products within 3 months before receiving the investigational vaccine;
• Received other study drugs or vaccines within 30 days before receiving the investigational vaccine;
• Received live attenuated vaccines within 14 days before receiving the investigational vaccine;
• Received subunit or inactivated vaccines within 7 days before receiving the investigational vaccine;
• Various acute diseases or acute exacerbation of chronic diseases within 7 days;
• Fever before vaccine inoculation, axillary temperature >37.5°C;
• Any other factors which are unsuitable for participation in the clinical trial as judged by the investigator.

Exclusion criteria

for Inoculation of the Second Dose of Vaccine:

• Any serious adverse event related to the inoculation of the investigational product;
• Hypersensitivity after vaccine inoculation (including urticaria/rash appeared within 30 minutes after inoculation);
• Any confirmed or suspected autoimmune disease or immunodeficiency disease, including human immunodeficiency virus (HIV) infection;
• If acute or newly onset chronic disease occurs during vaccine inoculation;
• The investigator judged that other significant reactions occur (including serious pain, serious swelling, serious activity limitation, continuous hyperthermia, serious headache or other systemic or local reactions);
• The patient develops acute disease when vaccine is inoculated (acute diseases means the moderate or severe disease with or without fever);
• Axillary temperature >37.5°C when vaccine is inoculated;
• The patient has received subunit inactivated vaccine within 7 days or live attenuated vaccines within 14 days.