A Phase Ⅱ Clinical Trial of Recombinant Corona Virus Disease-19 (COVID-19) Vaccine (Sf9 Cells)

This is a phase Ⅱ, single-center, randomized, double-blind, placebo-controlled study, to evaluate the immunogenicity and safety of the recombinant COVID-19 vaccine (Sf9 cells) in the subjects from healthy adults and elderly adults aged 18 years and above (aged 18-60 and 60-85 years) . The phase Ⅱ clinical trials designed 8 research group, including two immunization procedures (0, 21 days and 0, 14, 28 days), two doses (20μg/0.5ml, 40μg/1.0ml) and two ages group (adults and elder): Each group including 120 participants. Vaccination or placebo group will be randomly assigned to receive in a 5:1 ratio, 960 in total.

Inclusion criteria

• Aged 18 years and above.
• Able to understand the content of informed consent and willing to sign the informed consent.
• Able and willing to complete all the secluded study process during the whole study follow-up period (about 7 months).
• Axillary temperature ≤37.0℃.
• General good health as established by medical history and physical examination.

Exclusion criteria

First dose exclusion criteria:

• Positive serum immunoglobulin M (IgM) and IgG to the SARS-CoV-2.
• A Known History of HIV infection
• Family history of seizure, epilepsy, brain or mental disease.
• Participant that has an allergic history to any ingredient of vaccines.
• Woman who is pregnant, breast-feeding or positive in pregnancy test on day of enrollment, or is planning to be pregnant during the next 6 months.
• Any acute fever disease or infections.
• Have a medical history of SARS.
• Have serious cardiovascular diseases, such as arrhythmia, conduction block, myocardial infarction, severe hypertension and not well-controlled.
• Major chronic illness, such as asthma, diabetes, or thyroid disease, and not well-controlled.
• Hereditary angioneurotic edema or acquired angioneurotic edema.
• Urticaria in last one year.
• Asplenia or functional asplenia.
• Platelet disorder or other bleeding disorder may cause injection contraindication.
• Faint at the sight of blood or needles.
• Prior administration of immunodepressant or corticosteroids, antianaphylactics treatment, cytotoxic treatment in last 6 months.
• Prior administration of blood products in last 4 months.
• Prior administration of other research medicines in last 1 month.
• Prior administration of attenuated vaccine in last 1 month.
• Prior administration of subunit vaccine or inactivated vaccine in last 14 days.
• Being treated for tuberculosis.
• Any condition that in the opinion of the investigators may interfere with the evaluation of study objectives.

Exclusion criteria

for subsequent doses:

• Patients with severe allergic reactions after the previous dose of vaccination;
• Patients with serious adverse events causally related to the previous dose of vaccination.