Study of Recombinant Protein Vaccine Formulations Against COVID-19 in Healthy Adults 18 Years of Age and Older

Inclusion Criteria:

- Aged 18 years of age or older on the day of inclusion.

- Informed consent form had been signed and dated.

- Able to attend all scheduled visits and complied with all study procedures.

Exclusion Criteria:

- Participant was pregnant, or lactating, or of childbearing potential and not used an
effective method of contraception or abstinence from at least 4 weeks prior to the
first vaccination until at least 12 weeks after the last vaccination. To be considered
of non-childbearing potential, a female was post-menopausal for at least 1 year or
surgically sterile.

- Receipt of any vaccine in the 30 days preceding the first study vaccination or planned
receipt of any vaccine in the 30 days following the last study vaccination except for
influenza vaccination, which might be received at least 2 weeks before and a minimum
of 2 weeks after study vaccines.

- Prior administration of a coronavirus vaccine SARS-CoV-2, SARS-CoV, Middle East
Respiratory Syndrome).

- Known or suspected congenital or acquired immunodeficiency; or receipt of
immunosuppressive therapy, such as anti-cancer chemotherapy or radiation therapy,
within the preceding 6 months; or long-term systemic corticosteroid therapy
(prednisone or equivalent for more than 2 consecutive weeks within the past 3 months).

- History of SARS-CoV-2 infection, confirmed either clinically, serologically, or
microbiologically

- Chronic illness or condition considered to potentially increase the risk for severe
COVID illness or that, in the opinion of the Investigator, was at a stage where it
might interfere with study conduct or completion.

- Receipt of any therapy known to had in-vitro antiviral activity against SARS-CoV-2
within 72 hours prior to the first blood drew.

- Health care workers provided direct participant care for COVID-19 participants.

The above information was not intended to contain all considerations relevant to a
participant's potential participation in a clinical trial.