NCT05330975

A Study of mRNA-1345 Vaccine Targeting Respiratory Syncytial Virus (RSV) in Adults ≥50 Years of Age

A Phase 3 Randomized, Observer-Blind, Study to Evaluate Safety, Tolerability, and Immunogenicity of mRNA-1345, an mRNA Vaccine Targeting Respiratory Syncytial Virus (RSV), When Given Alone or Coadministered With a Seasonal Influenza Vaccine or SARS-CoV-2 Vaccine and When Given as an Open-label Boost at 1 Year Following a Primary Dose in Adults ≥ 50 Years of Age

• Status: Completed
• Phase: Phase 3
• Study type: Interventional
• Enrollment: 3,317 (actual)
• Sponsor: ModernaTX, Inc. · Industry
• Sex: All
• Age: 50 Years
• Healthy volunteers: Accepted

Summary

The main purposes of Part A of this study are to evaluate the safety, tolerability, and immunogenicity of mRNA-1345 coadministered with a seasonal influenza vaccine (Afluria® Quadrivalent); to evaluate the impact of coadministered influenza vaccine on the immune response to RSV-A; and to evaluate the impact of coadministered RSV vaccine on the immune response to influenza. The main purposes of Part B of this study are to evaluate the safety, tolerability, and immunogenicity of mRNA-1345 coadministered with mRNA-1273.214; to evaluate the effect of coadministered mRNA-1273.214 on the immune response to RSV-A; and to evaluate the effect of coadministered RSV vaccine on the immune response to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The main purposes of Part C (single arm, open-label) of this study are to evaluate the safety and tolerability of a booster dose (BD) of mRNA-1345 administered at 1 Year following a primary dose; to evaluate the immune response to RSV-A of a BD of mRNA 1345 administered at 1 Year following a primary dose; and to evaluate the immune response to RSV-B of a BD of mRNA-1345 administered at 1 Year following a primary dose.

Conditions

• Respiratory Syncytial Virus

Interventions

Type	Name	Description
BIOLOGICAL	Placebo	0.9% sodium chloride (normal saline) injection
BIOLOGICAL	mRNA-1345	Sterile liquid for injection
BIOLOGICAL	Afluria® Quadrivalent	single-dose, pre-filled syringe for injection
BIOLOGICAL	mRNA-1273.214	Sterile liquid for injection

Timeline

• Start date: 2022-04-01
• Primary completion: 2024-11-08
• Completion: 2024-11-08
• First posted: 2022-04-15
• Last updated: 2025-12-30
• Results posted: 2025-12-30

Locations

62 sites across 1 country: United States

Regulatory

• FDA-regulated drug study