Key Inclusion Criteria:

- Children 5 through 11 years of age at their first appointment.

- Children with at least 1 underlying stable medical condition that increases their
risk of severe COVID-19, as listed in the protocol.

Key Exclusion Criteria:

- Children who have had confirmed COVID-19 within the last 5 months (150 days).

- Children who have received a COVID-19 vaccine, either as part of a research study or
an approved vaccine, within the last 5 months (150 days).

- Children who have received a 2025-2026 seasonal COVID-19 vaccination.

- Children with a history of myocarditis or pericarditis.

- Children with a previous or current diagnosis of Multisystem Inflammatory Syndrome
in Children (MIS-C)

- Children with a medical condition wherein they would be considered for a second dose
of COVID-19 vaccine to protect against risk of severe COVID-19 based on standard of
care.

Refer to the study contact for further eligibility details.