NCT06097299

A Study of mRNA-1345, an mRNA Vaccine Targeting Respiratory Syncytial Virus, in Children 2 to <18 Years of Age at High Risk of Respiratory Syncytial Virus

A Phase 2, Randomized, Observer-blind Study to Evaluate the Safety, Reactogenicity, and Immunogenicity of mRNA-1345, an mRNA Vaccine Targeting Respiratory Syncytial Virus, in Children 2 to <18 Years of Age at High Risk of Respiratory Syncytial Virus Disease

• Status: Completed
• Phase: Phase 2
• Study type: Interventional
• Enrollment: 346 (actual)
• Sponsor: ModernaTX, Inc. · Industry
• Sex: All
• Age: 2 Years – 17 Years
• Healthy volunteers: Accepted

Summary

Part A: The purpose is to evaluate the safety, reactogenicity, and immunogenicity of mRNA-1345 in children aged 2 to \<5 years (Cohort 1) and in children at high risk of respiratory syncytial virus (RSV) disease 5 to \<18 years of age (Cohort 2) to inform the dose level selection for the next phase of development (Phase 3). Part B: The purpose is to provide surveillance for RSV disease for the next RSV season (6 months after re-enrollment) and safety follow-up for Cohort 1 participants that were enrolled and dosed in Part A.

Conditions

• Respiratory Syncytial Virus

Interventions

Type	Name	Description
BIOLOGICAL	mRNA-1345	Sterile liquid for injection
BIOLOGICAL	Placebo	0.9% sodium chloride (normal saline) injection

Timeline

• Start date: 2023-10-24
• Primary completion: 2025-06-27
• Completion: 2025-06-27
• First posted: 2023-10-24
• Last updated: 2025-07-10

Locations

50 sites across 2 countries: United States, Panama

Regulatory

• FDA-regulated drug study