Study to Evaluate Safety and Immunogenicity of COVID-19 Vaccine in Children 6 Months to < 12 Years

Inclusion Criteria:

To be included in this study, each individual must satisfy all of the following criteria:

1. Pediatric participants 6 months to < 12 years of age at randomization, determined tobe healthy or medically stable by the investigator (based on review of healthstatus, vital signs [to include body temperature], medical history, and targetedphysical examination [to include body weight]). Vital signs must be within thenormal range prior to the first vaccination, according to the child's age, sex,weight, and height/length.

2. For children from 6 months to < 12 months of age: born at full-term (≥ 37 weeksgestation) with a minimum birth weight of 2.5 kilograms (kg).

3. Participant and parent(s)/caregiver(s) or legally acceptable representative willingand able to give informed consent and assent, as required, prior to study enrollmentand to comply with study procedures.

4. Participants of childbearing potential (defined as any participant who hasexperienced menarche and who is NOT surgically sterile [ie, hysterectomy, bilateraltubal ligation, or bilateral oophorectomy]) must agree to be heterosexually inactivefrom at least 28 days prior to enrollment and through 3 months after the lastvaccination OR agree to consistently use a highly effective contraception methodfrom at least 28 days prior to enrollment and through 3 months after the lastvaccination.

5. Agree not to participate in another SARS-CoV-2 prevention trial for the duration ofthe study.

Exclusion Criteria:

If an individual meets any of the following criteria, he or she is ineligible for this study:

1. Any acute illness/infection (according to investigator judgment) on the day ofvaccination or febrile illness (temperature ≥ 100.4°F [≥ 38.0°C]). A prospectivesubject should not be included in the study until the condition has resolved or thefebrile event has subsided.

2. Unstable acute or chronic illness. Criteria for unstable medical conditions include:

3. Substantive changes in chronic prescribed medication (change in class orsignificant change in dose) in the past 2 months.

4. Currently undergoing workup of undiagnosed illness that could lead to adiagnosis of a new condition. NOTE: Well-controlled human immunodeficiency virus [HIV] infection with undetectableHIV ribonucleic acid [RNA < 50 copies/mL] and CD4 count > 200 cells/µL for at least 1 year, documented within the last 6 months, is NOT considered an unstable chronicillness. Participant's or parent's/caregiver's verbal report will suffice asdocumentation.

5. Participation in research involving an investigational product (drug/biologic/device) administered within 45 days prior to the first studyvaccination.

6. History of a previous laboratory-confirmed diagnosis of SARS-CoV-2 infection orCOVID-19.

7. Prior administration of an investigational, authorized, or approved Coronavirusvaccine (ie, against either SARS-CoV, SARS-CoV-2, or MERS CoV) or expected receiptduring the period of study follow-up.

8. Previous or current diagnosis of MIS-C.

9. Receipt of medications intended to prevent or treat COVID-19.

10. Received any vaccine within 14 days prior to first study vaccination or plannedreceipt of any vaccine before Day 49 (ie, 28 days after the second vaccination),except for influenza vaccination, which may be received > 14 days prior to or > 14days after any study vaccination.

11. Known or suspected congenital or acquired immunodeficiency or autoimmunedisease/condition; or receipt of immunosuppressive therapy, such as anti-cancerchemotherapy or radiation therapy; or long-term systemic corticosteroid therapy (prednisone or equivalent for > 14 continuous days) within 90 days prior to firststudy vaccination. NOTE: An immunosuppressant dose of glucocorticoid is defined as asystemic dose ≥ 20 mg of prednisone per day or equivalent. The use of topical,inhaled, and nasal glucocorticoids is permitted. Topical tacrolimus and ocularcyclosporin are permitted. Stable autoimmune endocrine disorders (eg, thyroiditis,pancreatitis), including stable diabetes mellitus type 1, or participants with ahistory of Kawasaki disease are NOT excluded.

12. Received immunoglobulin or blood-derived products within 90 days prior to firststudy vaccination.

13. Active cancer (malignancy) on chemotherapy within 1 year prior to first studyvaccination (with the exception of malignancy cured via excision, at the discretionof the investigator).

14. Any known allergies to products contained in the investigational product.

15. Participants who are breastfeeding a child, pregnant or who plan to become pregnantwithin 3 months following the last study vaccination.

16. Any other condition that, in the opinion of the investigator, would pose a healthrisk to the participant if enrolled or could interfere with the evaluation of thetrial vaccine or interpretation of study results.

17. Study team member or first-degree relative of any study team member (inclusive ofSponsor, and study site personnel involved in the study).

18. Current participation in any other COVID-19 prevention clinical trial.

19. Participants with a history of myocarditis or pericarditis.