NCT06686654

Study of a Human Metapneumovirus/Respiratory Syncytial Virus mRNA Vaccine Candidate Encapsulated in a Lipid Nanoparticle-based Formulation in Adults Aged 60 Years and Older

A Phase 1/2, Randomized, Observer-blind, Placebo-controlled Multi-arm Study to Evaluate the Safety and Immunogenicity of an hMPV/RSV mRNA Vaccine Candidate in Adult Participants Aged 60 Years and Older

• Status: Active Not Recruiting
• Phase: Phase 1 / Phase 2
• Study type: Interventional
• Enrollment: 1,530 (actual)
• Sponsor: Sanofi Pasteur, a Sanofi Company · Industry
• Sex: All
• Age: 60 Years
• Healthy volunteers: Accepted

Summary

The aim of this study is to evaluate the safety and immunogenicity of a human metapneumovirus (hMPV) / respiratory syncytial virus (RSV) mRNA vaccine candidate encapsulated in a lipid nanoparticle (LNP) based formulation (hereafter referred to as hMPV/RSV vaccine) for the prevention of lower respiratory tract disease (LRTD) caused by hMPV and/or RSV among adults aged 60 years and older. The study will also evaluate the safety and immunogenicity of a booster vaccination using a bivalent hMPV/RSV mRNA vaccine candidate (hereafter referred to as RSV+hMPV mRNA vaccine candidate). Overall, the study is designed to address the following goals: * Assess the safety profile of the candidate formulations. * Describe the immunogenicity profile of the candidate formulations. * Select the vaccine formulations (dose) for future development. * Assess the safety and immunogenicity of a booster vaccination with the RSV + hMPV mRNA vaccine candidate administered 12 months after primary vaccination with a licensed RSV vaccine. The study duration is as follows: -Six months each for the Sentinel and Main Cohorts; up to 12 months for the Expansion Cohort, and 6 additional months for the Booster Cohort Treatment duration: * Stage 1 Sentinel Cohort: 1 intra-muscular (IM) injection. Participants will be followed for 6 months post vaccination * Stage 1 Main Cohort: 1 IM injection. Participants will be followed for 6 months post vaccination * Stage 2 Expansion Cohort: 1 IM injection. Participants in the licensed RSV vaccine arm will be followed for 12 months post-vaccination; the remainder of the participants will be followed up to 8 months post-vaccination * Stage 2 Booster Cohort: 1 IM injection 12 months post-primary vaccination. Participants will be followed for 6 months post-booster vaccination

Conditions

• Human Metapneumovirus Immunization
• Respiratory Syncytial Virus Immunization

Interventions

Type	Name	Description
BIOLOGICAL	Investigational hMPV/RSV vaccine	Investigational hMPV/RSV vaccine administered intramuscularly
BIOLOGICAL	Investigational hMPV vaccine (monovalent)	Investigational hMPV vaccine (monovalent) administered intramuscularly
BIOLOGICAL	Investigational RSV vaccine (monovalent)	Investigational RSV vaccine (monovalent) administered intramuscularly
BIOLOGICAL	Licensed RSV Vaccine	Licensed RSV vaccine administered intramuscularly
BIOLOGICAL	Placebo	Placebo administered intramuscularly
BIOLOGICAL	Investigational RSV+hMPV vaccine	Investigational RSV+hMPV vaccine administered intramuscularly

Timeline

• Start date: 2024-11-11
• Primary completion: 2027-01-18
• Completion: 2027-01-18
• First posted: 2024-11-13
• Last updated: 2025-12-11

Locations

24 sites across 1 country: United States

Regulatory

• FDA-regulated drug study