safety and immunogenicity study of inactivated vaccine for prophylaxis of sars cov-2 infection (covid-19)

Conditions: COVID-19

Summary: this study is a randomized, double-blinded, and placebo controlled phase ⅰ/ⅱ clinical trial of the sars-cov-2 inactivated vaccine manufactured by sinovac research \& development co., ltd. the purpose of this study is to evaluate the safety and immunogenicity of the experimental vaccine in healthy adults aged 18\~59 years.

this study is a randomized, double-blinded, single-center, placebo-controlled phase ⅰ/ⅱ clinical trial in adults aged 18\~59 years. the purpose of this study is to evaluate the immunogenicity and safety of the experimental sars-cov-2 inactivated vaccine. the experimental vaccine and placebo were both manufactured by sinovac research \& development co., ltd. a total of 744 subjects will be enrolled, with 144 at phase ⅰ, and 600 at phase ⅱ. all of participants in phase ⅰ will be assigned to receive two doses of experimental vaccine or placebo on the schedule of day 0,14 or day 0,28.300 participants in phase ⅱ will be assigned to receive two doses of experimental vaccine or placebo on the schedule of day 0,14 or day 0,28 and one dose of booster immunization will be given 6 months after primary immunization of day 0,14 or day 0,28.the other 300 participants in phase ⅱ will be assigned to receive three doses of experimental vaccine or placebo on the schedule of day 0,14,42 or 0,28,56 .

Eligibility criteria:
inclusion criteria: * healthy adults aged 18-59 years; * proven legal identity; * participants should be capable of understanding the informed consent form, and such form should be signed prior to enrolment ; exclusion criteria: * travel history / residence history of wuhan city and surrounding areas, or other communities with case reports within 14 days; * history of contact with a sars-cov-2 infection (positive in nucleic acid test) within 14 days; * have contacted patients with fever or respiratory symptoms from wuhan and surrounding areas, or from communities with case reports within 14 days; * have contacted patients with fever or respiratory symptoms from wuhan and surrounding areas, or from communities with case reports within 14 days; * self-reported history of sars; * self-reported history of new coronavirus infection; * positive in serum antibodies (igg or igm) screening of covid-19; * positive in nasopharyngeal swabs or anal swabs through rt-pcr; * women who are breastfeeding, pregnant or planning to become pregnant during the study period; * bmi≥35 kg/m2; * history of asthma, history of allergy to the vaccine or vaccine components, or serious adverse reactions to the vaccine, such as urticaria, dyspnea, and angioedema; * congenital malformations or developmental disorders, genetic defects, severe malnutrition, etc.; * autoimmune disease or immunodeficiency / immunosuppression; * suffering from severe chronic diseases, severe cardiovascular diseases, hypertension and diabetes that cannot be controlled by drugs, liver and kidney diseases, malignant tumors, etc.; * severe neurological disease (epilepsy, convulsions or convulsions) or mental illness; * thyroid disease or history of thyroidectomy, spleenlessness, functional spleenlessness, spleenlessness 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; * abnormal laboratory test results in the physical examination such as clinically significant abnormal hematology and biochemistry beyond the reference value range (only applicable to phase i clinical trials); * history of alcohol or drug abuse; * receipt of blood products within 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; * attacks of acute diseases or 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 participating in the clinical trial.