The purpose of this study is to learn about the safety, tolerability, and immunogenicity of an updated vaccine against COVID-19, called BNT162b2 (2025/2026 formulation). This study is seeking participants 5 through 11 years of age who: * have at least 1 underlying condition that puts them at high risk for severe outcomes from COVID-19, * and are medically stable. All participants in this study will receive 1 vaccine dose given in the muscle of their arm of a BNT162b2 (2025/2026 formulation) vaccine which targets the COVID-19 virus, specifically the strain selected for the 2025-2026 COVID-19 viral respiratory season. Participants will take part in this study for about 6 months and will need to visit the clinical study site at least 2 times.
See this in plain English?
AI-rewrites the medical criteria so a patient or caregiver can understand them. Always confirm with the trial site.
Percentage of participants reporting local reactions
Timeframe: For up to 7 days after vaccination
Percentage of participants reporting systemic events
Timeframe: For up to 7 days after vaccination
Percentage of participants reporting adverse events
Timeframe: Through 1 month after vaccination
Percentage of participants reporting serious adverse events
Timeframe: Through 6 months after vaccination
Geometric Mean Fold Rises (GMFRs)
Timeframe: From before vaccination to 1 month after vaccination