Overview

In this trial, a total of 50 subjects were recruited; the test vaccines were divided into 3 groups, low-dose vaccine groups, high-dose vaccine groups, and placebo groups. The first-stage randomized participants in the low-dose group (20 cases) and the placebo group (5 cases) were evaluated for 7 days. After the 7-day safety data was evaluated and agreed by the DSMB, the second-stage study was conducted. Into the high-dose group (20 cases) and placebo group (5 cases) subjects; follow-up to 30 days, after the safety assessment by the investigator and consent, then inoculate the second dose. Observation was performed for 1.0 hour after the second dose. The researchers conducted a safety evaluation and agreed to follow-up after discharge.

Eligibility

Inclusion Criteria:

• Comply with the observation age of this clinical trial: 18-59 years old (both included) adults.
• The subjects themselves voluntarily agreed to participate in the study, and signed an informed consent form, and can provide legal identification; understand and abide by the requirements of the trial protocol; can participate in a half-year follow-up.
• Body temperature under armpit <37.3 .
• Body mass index (BMI) at 18-28kg / m (inclusive).
• Female and male subjects of childbearing age took effective contraception during the study.

Exclusion Criteria:

• The vital signs, physical examination and laboratory test indicators of the population specified in the plan are abnormal and have clinical significance as determined by the clinician;
• Have a history of severe allergies to any component of the research vaccine, including aluminum preparations, such as: anaphylactic shock, allergic laryngeal edema, allergic purpura, thrombocytopenic purpura, local allergic necrosis (Arthus reaction); or any previous History of serious side effects of vaccines or drugs, such as allergies, urticaria, skin eczema, dyspnea, angioedema, etc .
• Those with a history of SARS and COVID-19, meet any of the following:
  1. previous history of SARS-CoV and SARS-CoV-2 infection or morbidity;
  2. during the current SARS-CoV-2 epidemic, there is a diagnosis with the new crown Patient / suspected patient contact history;
  3. positive for SARS-CoV-2 IgM and / or IgG antibodies;
  4. positive for real-time fluorescent RT-PCR nucleic acid.
• Have taken antipyretics or painkillers within 24 hours before the first dose of vaccine.
• Inoculate subunit vaccine and inactivated vaccine within 14 days before the first dose of vaccination, and inoculate live attenuated vaccine within 30 days.
• People with the following diseases:
  1. Acute febrile illness;
  2. Digestive system diseases (eg, diarrhea, abdominal pain, vomiting, etc.) in the past 7 days;
  3. Congenital malformations or developmental disorders, genetic defects, severe malnutrition, etc .;
  4. Congenital or acquired immunodeficiency or autoimmune disease history or within 6 months of receiving immunomodulator treatment, such as hormones; or monoclonal antibodies; or thymosin; or interferon, etc .; but local medications (such as ointment are allowed , Eye drops, inhalation or nasal spray), local administration should not exceed the dosage recommended in the instructions or have any signs of systemic exposure;
  5. The chest imaging examination is clinically significant if the investigator judges that the abnormality is clinically positive, or any positive of hepatitis B surface antigen, hepatitis C virus antibody, human immunodeficiency virus HIV antibody or syphilis specific antibody;
  6. Neurological diseases or neurodevelopmental disorders (eg, migraine, epilepsy, stroke, seizures in the last three years, encephalopathy, focal neurological deficit, Guillain-Barr syndrome, encephalomyelitis or transverse myelitis ); History of mental illness or family history;
  7. Functional spleenlessness, and spleenlessness or splenectomy for any reason;
  8. There are serious chronic diseases or conditions that cannot be controlled smoothly in the advanced stage, such as diabetes and thyroid disease;
  9. Severe liver and kidney diseases; respiratory diseases that currently require daily medication (eg, chronic obstructive pulmonary disease [COPD], asthma) or any treatment that exacerbates respiratory diseases (eg, exacerbated asthma) within the last 5 years; suffers History of severe cardiovascular disease (such as congestive heart failure, cardiomyopathy, ischemic heart disease, arrhythmia, conduction block, myocardial infarction, pulmonary heart disease) or myocarditis or pericarditis;
  10. have thrombocytopenia, any coagulopathy, or receive anticoagulant treatment, etc .;
  11. Cancer patients;
  12. Have received blood or blood-related products, including immunoglobulin within 3 months; or plan to use it during the study.
• Lactating women or pregnant women (including blood or urine pregnancy test positive).
• Any research or unregistered product (medicine, vaccine, biological product or device) other than the research product was used within 3 months before the application of the test drug / vaccine, or planned to be used during the study.
• People with halo and halo needles.
• The investigator believes that the presence of any disease or condition in the subject may put the subject at an unacceptable risk; the subject cannot meet the protocol requirements; and interfere with the assessment of vaccine response.