NCT05436834

A Study to Evaluate the Safety and Immunogenicity of the mRNA COVID-19 Vaccines in Healthy Children Between 6 Months to Less Than 6 Years of Age

An Open-Label, Phase 3 Study to Evaluate the Safety and Immunogenicity of mRNA Vaccines for SARS-CoV-2 Variants in Participants Aged 6 Months to < 6 Years

• Status: Completed
• Phase: Phase 3
• Study type: Interventional
• Enrollment: 1,807 (actual)
• Sponsor: ModernaTX, Inc. · Industry
• Sex: All
• Age: 6 Months – 5 Years
• Healthy volunteers: Accepted

Summary

This study will evaluate the safety and immunogenicity of the mRNA-1273.214 vaccine for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variant of concerns (VOCs) in participants aged 6 months to \<6 years, when administered as a primary series in SARS-CoV-2 vaccine-naïve participants (Part 1) and a single booster dose (BD) given to participants who previously received 2 doses of the mRNA-1273 vaccine as a primary series (Part 2); and will evaluate the safety and immunogenicity of the mRNA-1273.815 vaccine, when administered as a BD in participants aged 6 months to \<6 years (Part 3) and when administered to SARS-CoV-2 vaccine-naïve participants aged 2 years to \<5 years of age (Part 4).

Detailed description

Part 1 will enroll participants aged 6 months to \<6 years who have not been previously vaccinated against SARS-CoV-2. Participants will receive 2 doses of the mRNA-1273.214 vaccine. Part 2 will enroll participants aged 6 months to \<6 years who have previously been vaccinated with a mRNA-1273 primary series in Study mRNA-1273-P204 (NCT04796896). Participants will receive a single BD of the mRNA-1273.214 vaccine, at least 4 months after completion of the mRNA-1273 primary series. Part 3 will enroll participants aged 6 months to \<6 years who have previously been vaccinated with an authorized/approved COVID-19 vaccine. Participants will receive a BD of the mRNA-1273.815 vaccine at least 4 months after the last receipt of a COVID-19 vaccine. Part 4 will evaluate mRNA-1273.815 vaccine administered as a single dose to SARS-CoV-2 vaccine-naïve participants aged 2 years to \<5 years of age enrolled in Cohort A (Part 4A), compared to 2 doses given to SARS-CoV-2 vaccine-naïve participants aged 6 months to \<2 years enrolled in Cohort B (Part 4B).

Conditions

• SARS-CoV-2

Interventions

Type	Name	Description
BIOLOGICAL	mRNA-1273.214	Sterile liquid for injection
BIOLOGICAL	mRNA-1273.815	Sterile liquid for injection

Timeline

• Start date: 2022-06-21
• Primary completion: 2025-10-20
• Completion: 2025-10-20
• First posted: 2022-06-29
• Last updated: 2025-11-26

Locations

74 sites across 7 countries: United States, Argentina, Chile, Colombia, Dominican Republic, Panama, Puerto Rico

Regulatory

• FDA-regulated drug study