Study of the Commercial Scale SARS-CoV-2 Vaccine Against the Pilot Scale Among Adults, and Bridging Study of the Immunogenicity in Elderly Against That in Adults

Inclusion Criteria: 1. Healthy adults aged 18-59 or elderly aged ≥60 years; 2. Proven legal identity. Exclusion Criteria: 1. Travel/residence history of communities with reported cases within 14 days before trial; 2. History of exposure to Novel Coronavirus infection (nucleic acid positive) within 14 days prior to the trial; 3. Exposed to patients with fever or respiratory symptoms from communities with reported cases within 14 days prior to the trial; 4. Two or more cases of fever and/or respiratory symptoms in a small area such as home, office, school and class within 14 days prior to the trial; 5. History of SARS-CoV-2 infection; 6. History of asthma, history of allergy to vaccines or vaccine ingredients, and severe adverse reactions to vaccines, such as urticaria, dyspnea, and angioneurotic edema; 7. Congenital malformations or developmental disorders, genetic defects, severe malnutrition, etc.; 8. Autoimmune disease or immunodeficiency/immunosuppression; 9. Patients with serious chronic diseases, serious cardiovascular diseases, uncontrolled hypertension and diabetes, liver and kidney diseases, malignant tumors, etc.; 10. Serious neurological disorder (epilepsy, convulsions or convulsions) or psychosis; 11. History of thyroid disease or thyroidectomy, absence of spleen, functional absence of spleen, and absence of spleen or splenectomy caused by any circumstance; 12. Coagulation dysfunction (such as coagulation factor deficiency, coagulation disease, platelet abnormality) or obvious bruising or coagulation disorder diagnosed by doctors; 13. Immunosuppressive therapy, cytotoxic therapy, inhaled corticosteroids (excluding corticosteroid spray therapy for allergic rhinitis, and surface corticosteroid therapy for acute non-complicated dermatitis) in the past 6 months; 14. Long history of alcohol or drug abuse; 15. Received blood products within 3 months prior to receiving the vaccine; 16. Received other research drugs within 30 days prior to receiving the vaccine; 17. Received live attenuated vaccine within 14 days prior to receiving the vaccine; 18. Received subunit or inactivated vaccine within 7 days prior to receiving the vaccine; 19. Onset of various acute or chronic diseases within 7 days prior to the study; 20. Axillary temperature of \>37.0℃ before inoculation of the vaccine; 21. Those who are already pregnant (including a positive urine pregnancy test) or are breastfeeding, planning to become pregnant within 2 months; 22. In the opinion of the investigator, the participants had any other factors that made them unsuitable to participate in the clinical trial.