Inclusion Criteria:

1. Persons aged 18-59 with full capacity for civil conduct;

2. Subjects voluntarily participate in the study, sign informed consent, provide valid
identification, understand and comply with the requirements of the study protocol;

3. Female subjects of reproductive age agree to use effective contraceptive measures
from the beginning of the study to 12 months after full vaccination.

Exclusion Criteria:

1. Suspected or confirmed fever within 72 hours before enrollment, or armpit
temperature ≥37.3℃ on the day of enrollment;

2. Diastolic blood pressure ≥100mmHg and/or systolic blood pressure ≥160mmHg before
screening;

3. people who currently have or have a history of COVID-19;

4. Persons suffering from the following diseases:

① have thrombocytopenia, any coagulation dysfunction or receive anticoagulant
treatment, etc.;

② history of congenital or acquired immune deficiency or autoimmune disease;
Received immunomodulators within 6 months, such as immunosuppressive doses of
glucocorticoids (dose reference: equivalent to prednisone 20mg/ day, over a week);
Or monoclonal antibodies; Or thymosin; Or interferon; However, topical use (such as
ointments, eye drops, inhalants or nasal sprays) is allowed;

③ Cancer patients (except basal cell carcinoma);

④ Patients with active tuberculosis, viral hepatitis and/or HIV antibody positive or
syphilis specific antibody positive;

⑤ Neurological disease or family history (e.g., migraines, epilepsy, stroke,
seizures in the last three years, encephalopathy, focal neurological deficits,
Guillain-Barre syndrome, encephalomyelitis or transverse myelitis); History of
mental illness or family history;

⑥ Functional absence of spleen, and absence of spleen or splenectomy caused by any
reason;

⑦ Serious chronic diseases or diseases in the advanced stage can not be controlled
smoothly, such as diabetes, thyroid diseases;

⑧ Severe liver and kidney diseases; Any current respiratory illness requiring
routine medication (e.g., chronic obstructive pulmonary disease [COPD], asthma) or
any exacerbation of respiratory illness (e.g., exacerbation of asthma) within the
last 5 years; A history of serious cardiovascular disease (e.g., congestive heart
failure, cardiomyopathy, ischemic heart disease, arrhythmia, conduction block,
myocardial infarction, cor pulmonale) or myocarditis or pericarditis.

5. A history of severe allergy to any vaccine, or to any component of the test vaccine,
including aluminum preparations, such as anaphylactic shock, allergic laryngeal
edema, allergic purpura, thrombocytopenic purpura, dyspnea, angiopantic edema, etc.;

6. Subunit vaccine and inactivated vaccine should be administered within 14 days before
the first dose of vaccine, and live attenuated vaccine should be administered within
30 days;

7. Have received blood or blood-related products, including immunoglobulin, within 3
months; Or planned use from the beginning of the study to 1 month after full
vaccination;

8. Those who have participated in or are participating in other CLINICAL trials related
to COVID-19, or who have received COVID-19 vaccines;

9. Lactating women or pregnant women (including women of childbearing age with positive
urine pregnancy test);

10. The Investigator believes that the subject has any disease or condition that may
place the subject at unacceptable risk; Subjects cannot meet the requirements of the
program; Conditions that interfere with the assessment of vaccine response.