A Study to Evaluate MVC-COV1901 Vaccine Against COVID-19 in Adult

Inclusion Criteria:

1. Male or female participant ≥ 20 to < 65 years, or ≥ 65 years of age at randomization.

2. Healthy adults or adults with pre-existing medical conditions who are in stable
condition. A stable medical condition is defined as disease not requiring significant
change in therapy or hospitalization for worsening disease 3 months before enrollment
and expected to remain stable for the duration of the study.

3. Female participant must:

1. Be either of non-childbearing potential, i.e. surgically sterilized (defined as
having undergone hysterectomy and/or bilateral oophorectomy and/or bilateral
salpingectomy; tubal ligation alone is not considered sufficient) or one year
post-menopausal;

2. Or, if of childbearing potential, be abstinent or agree to use medically
effective contraception from 14 days before screening to 30 days following the
last injection of study intervention. Acceptable forms include:

i. Implanted hormonal methods of contraception or placement of an intrauterine device
or intrauterine system ii. Established use of hormonal methods (injectable, pill,
patch or ring) combined with barrier methods of contraception: condom or occlusive cap
(diaphragm or cervical/vault caps) with spermicidal foam/gel/film/cream/suppository c.
Have a negative pregnancy test

4. Participant is willing and able to comply with all required study visits and follow-up
required by this protocol.

5. Participant has not travelled overseas within 14 days of screening and will not have
any oversea travelling throughout the study period.

6. Participant or the participant's legal representative must understand the procedures
of the study and provide written informed consent.

Exclusion Criteria:

1. Pregnant or breast feeding or have plan to become pregnant in 30 days after last
administration of study intervention.

2. Employees at the investigator's site, of the Sponsor or the contract research
organization (CRO) directly involved in the conduct of the study.

3. Currently receiving or received any investigational intervention within 30 days prior
to the first dose of study intervention.

4. Administered any licensed live-attenuated vaccines within 28 days or other licensed
non-live-attenuated vaccines within 7 days prior to the first dose of study
intervention.

5. Administered any blood product or intravenous immunoglobulin administration within 12
weeks prior to the first dose of study intervention.

6. Currently receiving or anticipate to receive concomitant immunosuppressive or
immune-modifying therapy (excluding inhaled, topical skin and/or eye drop-containing
corticosteroids, low-dose methotrexate, or < 2 weeks of daily receipt of prednisone
less than 20 mg or equivalent) within 12 weeks prior to the first dose of study
intervention.

7. Currently receiving or anticipate to receive treatment with tumor necrosis factor
(TNF)-α inhibitors, e.g. infliximab, adalimumab, etanercept within 12 weeks prior to
the first dose of study intervention.

8. Major surgery or any radiation therapy within 12 weeks prior to the first dose of
study intervention Medical Conditions

9. Immunosuppressive illness or immunodeficient state, including hematologic malignancy,
history of solid organ, bone marrow transplantation, or asplenia.

10. A history of autoimmune disease (systemic lupus, rheumatoid arthritis, scleroderma,
polyarthritis, thyroiditis, Guillain-Barré syndrome, etc.).

11. A history of malignancy with potential risk for recurrence after curative treatment,
or current diagnosis of or treatment for cancer (exceptions are squamous and basal
cell carcinomas of the skin and treated uterine cervical carcinoma in situ, at the
discretion of the investigator).

12. Bleeding disorder considered a contraindication to intramuscular injection or
phlebotomy.

13. Human immunodeficiency virus (HIV) antibody positive participants with CD4 count < 350
cells/mm3 or a detectable HIV viral load within the past year (low level variations
from 50-500 viral copies/mL or equivalent which do not lead to changes in
antiretroviral therapy [ART] are permitted).

14. Hepatitis B surface antigen (HBsAg) positive participant with positive hepatitis B e
antigen (HBeAg) or abnormal liver function.

15. Hepatitis C virus (HCV) antibody positive participants with detectable HCV ribonucleic
acid (RNA) viremia in recent 12 weeks.

16. Participant with ongoing acute diseases or serious medical conditions which will
interfere with adherence to study requirements, or the evaluation of any study
endpoint. Acute diseases or serious medical conditions include cardiovascular (e.g.
New York Heart Association Grade III or IV), pulmonary (e.g. chronic obstructive
pulmonary disease stage III or IV), hepatic (e.g. Child-Pugh Class C), neurologic
(e.g. dementia), metabolic (e.g. diabetes mellitus with hemoglobin A1c [HbA1c] > 8%),
renal (Stage 3 or worse chronic kidney disease), psychiatric condition (e.g.
alcoholism, drug abuse), current severe infections, medical history, physical
findings, or laboratory abnormality that in the investigators' opinion are not in
stable condition and participating in the study could adversely affect the safety of
the participant.

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17. Participant with previous known or potential exposure to SARS-CoV-1 or 2 viruses
(EXCEPT for those who have been tested negative and completed the 14-day
self-managements/ home quarantines/ home isolations) or received any other COVID-19
vaccine.

18. Participant with a history of hypersensitivity to any vaccine or a history of allergic
disease or reactions likely to be exacerbated by any component of the MVC-COV1901.

19. Body (oral, rectal, or ear) temperature ≥ 38.0°C or acute illness (not including minor
illnesses such as diarrhea or mild upper respiratory tract infection at the discretion
of the investigator) within 2 days before the first dose of study intervention.