NCT05639894

Study of a Respiratory Syncytial Virus Candidate Encapsulated in a Lipid Nanoparticle Based Formulation in Adults Aged 18 to 50 Years and 60 Years and Older

A Phase I/IIa, Randomized, Placebo-controlled Multi-arm Dose-finding Study to Evaluate the Safety and Immunogenicity of a RSV Vaccine Candidate in Adult Participants 18 to 50 Years of Age in Phase I, and 60 Years and Older in Phase IIa

• Status: Completed
• Phase: Phase 1 / Phase 2
• Study type: Interventional
• Enrollment: 865 (actual)
• Sponsor: Sanofi Pasteur, a Sanofi Company · Industry
• Sex: All
• Age: 18 Years
• Healthy volunteers: Accepted

Summary

Brief Summary of Stage 1: The purpose Stage 1 (Phase I/IIa) is to assess the safety and immunogenicity of a single intramuscular (IM) injection of 3 dose-levels of an Respiratory Syncytial Virus (RSV) vaccine candidate formulated with 2 different lipid nanoparticles (LNPs) in healthy adult participants aged between 18 to 50 years, and 60 years and older. The primary objectives of this stage are to assess the safety and immunogenicity profiles across the dose-level groups (low, medium, and high doses) with 2 LNPs. This stage will evaluate the safety and immunogenicity of a booster vaccination administered 12 months after the primary vaccination in a subset of the study population. Brief Summary of Stage 2: The study also also incorporates a Stage 2 (Phase IIa, dose-ranging design) that includes adults aged 60 years and older to assess the safety and immunogenicity of different doses of RSV vaccine encapsulated in one of the LNPs. In the Phase IIa dose-ranging stage, eligible participants will be randomly assigned in a 1:1:1 ratio to receive a single IM administration of RSV vaccine candidate doses, or placebo. Multiple safety analyses will be performed, minimally at D07 and D28. Additional analyses may be performed as data are available.

Detailed description

Stage 1: The duration of each participant's participation is 12 months for the Sentinel and Main Cohorts, 24 months overall for the subset of participants enrolled in the Booster Cohort. Treatment Duration: * Sentinel Cohort: 1 intra-muscular (IM) injection. Participants will be followed for 12 months post-vaccination. * Main Cohort: 1 IM injection. Participants will be followed for 12 months post-vaccination. * Booster Cohort: 1 IM injection 12 months after the primary vaccination. Participants will be followed for 12 months after administration of the booster dose. Stage 2: The duration of each participant's participation is approximately 6 months. Treatment Duration: 1 IM injection. Participants will be followed for approximately 6 months post vaccination

Conditions

• Respiratory Syncytial Virus Immunization

Interventions

Type	Name	Description
BIOLOGICAL	RSV vaccine candiate formulation 1	Pharmaceutical Form: Liquid frozen solution in a vial Route of Administration: Intramuscular injection
BIOLOGICAL	RSV vaccine candidate formulation 2	Pharmaceutical Form: Liquid frozen solution in a vial Route of Administration: Intramuscular injection
OTHER	Placebo	Pharmaceutical Form: Liquid Route of Administration: Intramuscular injection

Timeline

• Start date: 2022-11-17
• Primary completion: 2025-05-02
• Completion: 2025-05-02
• First posted: 2022-12-07
• Last updated: 2025-05-31

Locations

33 sites across 3 countries: United States, Australia, Puerto Rico

Regulatory

• FDA-regulated drug study