This study is a randomized, double-blinded, and placebo controlled phase 1&2 clinical trial of the SARS-CoV-2 inactivated vaccine manufactured by Sinovac Life Sciences Co. , Ltd. The purpose of this study is to evaluate the safety and immunogenicity of the experimental vaccine in healthy elderly aged 60 years and above.
This study is a randomized, double-blinded, single-center, placebo-controlled phase 1&2
clinical trial in healthy elderly aged 60 years and above. The experimental vaccine and
placebo were both manufactured by Sinovac Life Sciences Co. , Ltd. A total of 422 subjects
will be enrolled, with 72 in phase 1 and 350 in phase 2. 72 Subjects with 36 in medium-dosage
group and 36 in high-dosage group in phase 1 will receive two doses of primary immunization
according to the immunization schedule of day 0, 28 and the subjects at each dosage group
will be assigned in a 2:1 ratio to receive investigational vaccine or placebo
respectively.All enrolled subjects will receive 1 dose of booster immunization 1 year after
primary immunization.350 Subjects in phase 2 will receive two doses of primary immunization
according to the immunization schedule of day 0,28,the subjects will be assigned in a ratio
of 2:2:2:1 to receive the low dosage, medium dosage, high dosage vaccine, or placebo. All
enrolled subjects will received 1 dose of booster immunization(the third dose ) 6 months
after primary immunization.And subjects in medium-dosage group and high -dosage group will
receive the second booster dose (the fourth dose) 1 year after the second dose.
Biological: Two doses of medium dosage inactivated SARS-CoV-2 vaccine at the schedule of day 0,28
The inactivated SARS-CoV-2 vaccine was manufactured by Sinovac Research & Development Co., Ltd..Two doses of medium dosage (600SU/0.5ml) experimental vaccine at the schedule of day 0,28,and one dose of booster immunization(the third dose) with medium dosage (600SU/0.5ml) experimental vaccine 1 year after primary immunization at the schedule of day 0,28 in phaseⅠand 6 months after primary immunization at the schedule of day 0,28 in phase Ⅱ.And the second booster dose (the fourth dose) 1 year after the second dose.
Biological: Two doses of high dosage inactivated SARS-CoV-2 vaccine at the schedule of day 0,28
The inactivated SARS-CoV-2 vaccine was manufactured by Sinovac Research & Development Co., Ltd..Two doses of high dosage (1200SU/0.5ml) experimental vaccine at the schedule of day 0,28,and one dose of booster immunization(the third dose) with medium dosage (1200SU/0.5ml) experimental vaccine 1 year after primary immunization at the schedule of day 0,28 in phaseⅠand 6 months after primary immunization at the schedule of day 0,28 in phase Ⅱ.And the second booster dose (the fourth dose) 1 year after the second dose.
Biological: Two doses of placebo at the schedule of day 0,28
The placebo was manufactured by Sinovac Research & Development Co., Ltd., Two doses of placebo at the schedule of day 0,28,and one dose of booster immunization with placebo 1 year after primary immunization at the schedule of day 0,28 in phaseⅠand 6 months after primary immunization at the schedule of day 0,28 in phase Ⅱ.
Biological: Two doses of low dosage inactivated SARS-CoV-2 vaccine at the schedule of day 0,28
The inactivated SARS-CoV-2 vaccine was manufactured by Sinovac Research & Development Co., Ltd..Two doses of low dosage (300SU/0.5ml)experimental vaccine at the schedule of day 0,28,and one dose of booster immunization with low dosage (300SU/0.5ml) experimental vaccine 6 months after primary immunization at the schedule of day 0,28 in phase Ⅱ.
Inclusion Criteria:
- Healthy adults aged ≥60 years;
- Be able to understand and sign the informed consent voluntarily;
- Provide legal identification;
Exclusion Criteria:
- Travel / residence history of Wuhan city and surrounding areas or other communities
with case reports within 14 days prior to the enrolment;
- Contact with SARS-CoV-2 infected persons (positive for nucleic acid detection) within
14 days prior to the enrolment;
- Contact patients with fever or respiratory symptoms from Wuhan city and surrounding
areas, or from communities with case reports within 14 days prior to the enrolment;
- Two or more cases of fever and / or respiratory symptoms in a small contact area of
subjects, such as family, office, school class or other places within 14 days prior to
the enrolment;
- History of SARS;
- History of SARS-CoV-2 infection;
- History of asthma, allergy to vaccines or vaccine ingredients, and serious adverse
reactions to vaccines, such as urticaria, dyspnea, angioneuroedema;
- Congenital malformation or developmental disorder, genetic defect, severe
malnutrition, etc;
- Autoimmune disease or immunodeficiency / immunosuppression;
- Serious chronic disease, serious cardiovascular disease, hypertension and diabetes
that cannot be controlled by drugs, hepatorenal disease, malignant tumor, etc;
- Serious nervous system disease (epilepsy, convulsion or convulsion) or psychosis;
- Thyroid disease or history of thyroidectomy, asplenia, functional asplenia, asplenia
or splenectomy resulting from 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 non-complicated dermatitis
superficial corticosteroid therapy) in the past 6 months;
- Long history of alcohol or drug abuse;
- Receipt of blood products in the past 3 months;
- Receipt of other investigational drugs in the past 30 days;
- Receipt of attenuated live vaccines in the past 14 days;
- Receipt of inactivated or subunit vaccines in the past 7 days;
- Acute diseases or acute exacerbation of chronic diseases in the past 7 days;
- Axillary temperature >37.0°C;
- According to the investigator's judgment, the subject has any other factors that are
not suitable for the clinical trial.
Renqiu City Center for Disease Control and Prevention
Renqiu, Hebei, China
Yuliang Zhao, Master, Principal Investigator
Hubei Provincial Center for Disease Control and Prevention