> Trialight public data. Index of pages: https://trialight.com/llms.txt > Web page: https://trialight.com/data/trial/study-of-the-safety-and-immune-response-of-an-61db004f-a07f-4f37-97ff-4703ebcb05f3 > Record changed: 2026-10-13 # Study of the Safety and Immune Response of an Investigational mRNA Vaccine for the Prevention of Respiratory Syncytial Virus and/or Human Metapneumovirus in Participants Aged 18 to 49 Years and 60 Years and Older NCT06237296 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06237296) Phase Phase 1 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06237296) Recruitment status Completed Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06237296) Participants 558 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06237296) Lead sponsor Sanofi Pasteur, a Sanofi Company Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06237296) Start date 2024-01-23 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06237296) Number of sites 17 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06237296) ## Title and summary **Summary** The purpose of this study is to evaluate the safety and immunogenicity an investigational messenger ribonucleic acid (mRN)A vaccine for the prevention of lower respiratory tract disease (LRTD) caused by respiratory syncytial virus (RSV) and/or human metapneumovirus (hMPV) in older adults. A single intramuscular (IM) injection of 3 to 4 different doses of the RSV/hMPV mRNA vaccine candidate formulated with 2 different lipid nanoparticles (LNP) will be administered to healthy participants aged 18 to 49 years and 60 years and older. Treatment: \* RSV/hMPV mRNA / LNP 1 at 3-4 different doses or, \* RSV/hMPV mRNA / LNP 2 at 3-4 difference doses or, \* RSV mRNA / LNP 1 at 1 dose or, \* hMPV mRNA / LNP 1 at 1 dose Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06237296) **Short title** Study of the Safety and Immune Response of an Investigational mRNA Vaccine for the Prevention of Respiratory Syncytial Virus and/or Human Metapneumovirus in Participants Aged 18 to 49 Years and 60 Years and Older Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06237296) **Official title** A Phase I, Dose-escalation, Parallel-group, Randomized, Multi-center Study to Assess Safety and Immunogenicity of an RSV/hMPV mRNA Vaccine Candidate in Healthy Participants Aged 18 to 49 Years and 60 Years and Older. Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06237296) ## Status and phase **Registry reports results** No Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06237296) **Listing at source** Listed Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06237296) **Recruitment status** Completed Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06237296) **Phase** Phase 1 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06237296) **Study type** Interventional Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06237296) ## Dates **Completion date** 2025-02-11 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06237296) **First posted** 2024-02-01 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06237296) **Registry last updated** 2025-09-11 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06237296) **Primary completion date** 2025-02-11 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06237296) **Start date** 2024-01-23 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06237296) ## Size and sites **Actual participants** 558 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06237296) **Participants** 558 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06237296) **Participant count basis** Actual Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06237296) **Protocol amendments** 1 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06237296) **Number of sites** 17 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06237296) ## Sponsor and oversight **Data monitoring committee** No Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06237296) **Registry sponsor category** Industry Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06237296) **Lead sponsor** Sanofi Pasteur, a Sanofi Company Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06237296) **Source registry** ClinicalTrials.gov Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06237296) ## Identifiers **Registry ID** NCT06237296 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06237296) **ClinicalTrials.gov ID** NCT06237296 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06237296) **Registry record** Open registry record Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06237296) ## Study design **Allocation** Randomised **Model** Parallel groups **Purpose** Prevention **Masking** Triple masking **Masking description** \* Participants, Investigators and site staff remain blinded during study conduct, except dedicated study staff preparing/administering the study intervention. \* Sponsor study staff will remain unblinded, except laboratory staff who handle primary/secondary endpoints **Masked roles** Participants, Care providers, Investigators Sources for study design Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06237296) ## Outcomes ### Primary outcomes 1. Presence of unsolicited systemic immediate adverse events (AEs) Timeframe: Within 30 minutes after vaccination Number of participants experiencing immediate an immediate unsolicited systemic adverse event 2. Presence of solicited injection site or systemic reactions Timeframe: Within 7 days after vaccination Number of participants reporting: \* injection site reactions: pain, erythema and swelling \* systemic reactions: fever, headache, fatigue, myalgia, arthralgia and chills 3. Presence of unsolicited AEs Timeframe: Within 28 days after vaccination Number of participants experiencing unsolicited AEs 4. Presence of medically attended adverse events (MAAEs) Timeframe: Throughout study (up to approximately 6 months) Number of participants experiencing MAAEs 5. Presence of serious adverse events (SAEs) Timeframe: Throughout study (up to approximately 6 months) Throughout study (up to approximately 6 months) 6. Presence of adverse events of special interest (AESIs) Timeframe: Throughout study (up to approximately 6 months) Number of participants experiencing AESIs 7. Presence of out-of-range biological test results Timeframe: Within 7 days after vaccination Number of participants with biological safety assessment values out of normal range (as per the laboratory performing the test, including shift from baseline values) 8. RSV-A serum neutralizing antibody (nAb) titers at pre-vaccination (D01) and 28 days post- vaccination (D29) in the RSV/hMPV and monovalent RSV formulations Timeframe: Day 1 and Day 29 RSV-A serum nAb titers at pre-vaccination (D01), 28 days (D29) post-vaccination 9. RSV-B serum neutralizing antibody (nAb) titers at pre-vaccination (D01) and 28 days post- vaccination (D29) in the RSV/hMPV and monovalent RSV formulations Timeframe: Day 1 and Day 29 RSV-B serum nAb titers at pre-vaccination (D01), 28 days (D29) post-vaccination 10. hMPV- A serum neutralizing antibody (nAb) titers at pre-vaccination (D01) and 28 days post- vaccination (D29) in the RSV/hMPV and monovalent hMPV formulations Timeframe: Day 1 and Day 29 hMPV-A serum nAb titers at pre-vaccination (D01), 28 days (D29) post-vaccination ### Secondary outcomes 1. RSV A serum nAb titers at pre vaccination (D01), 28 days (D29), 3 months (D91), and 6 months (D181) post vaccination in the monovalent RSV formulation Timeframe: Day 1, Day 29, Day 91 and Day 181 RSV A serum nAb titers at pre vaccination (D01), 28 days (D29), 3 months (D91), and 6 months (D181) post vaccination 2. RSV B serum nAb titers at pre vaccination (D01), 28 days (D29), 3 months (D91), and 6 months (D181) post vaccination in the monovalent RSV formulation Timeframe: Day 1, Day 29, Day 91 and Day 181 RSV B serum nAb titers at pre vaccination (D01), 28 days (D29), 3 months (D91), and 6 months (D181) post vaccination 3. RSV A serum anti-F immunoglobulin G (IgG) antibody (Ab) titers at pre-vaccination (D01), 28 days (D29), 3 months (D91), and 6 months (D181) post vaccination in the monovalent RSV formulation Timeframe: Day 1, Day 29, Day 91 and Day 181 RSV A serum anti-F immunoglobulin G (IgG) antibody (Ab) titers at pre-vaccination (D01), 28 days (D29), 3 months (D91), and 6 months (D181) post vaccination 4. hMPV A serum nAb titers at pre vaccination (D01), 28 days (D29), 3 months (D91), and 6 months (D181) post vaccination in the monovalent hMPV formulations Timeframe: Day 1, Day 29, Day 91 and Day 181 hMPV A serum nAb titers at pre vaccination (D01), 28 days (D29), 3 months (D91), and 6 months (D181) post vaccination 5. hMPV A serum anti-F IgG Ab titers at pre vaccination (D01), 28 days (D29), 3 months (D91), and 6 months (D181) post vaccination in the monovalent hMPV formulations Timeframe: Day 1, Day 29, Day 91 and Day 181 hMPV A serum anti-F IgG Ab titers at pre vaccination (D01), 28 days (D29), 3 months (D91), and 6 months (D181) post vaccination Sources for outcomes Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06237296) ## Eligibility **Sex** All **Age groups** Adults, Older adults **Minimum age** 18 Years **Healthy volunteers** Yes ### Inclusion criteria \-Informed consent form (ICF) has been signed and dated ### Exclusion criteria Participants are excluded from the study if any of the following criteria apply: \-Any condition which, in the opinion of the Investigator, might interfere with the evaluation of the study objectives. \--The above information is not intended to contain all considerations relevant to a patient's potential participation in a clinical trial. Sources for eligibility Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06237296) ## Sites - Velocity Gardena Site Number : 8400011Gardena, United States - Velocity Clinical Research-Hallandale Beach- Site Number : 8400013Hallandale, United States - Advanced Clinical Research- Site Number : 8400005Meridian, United States - Velocity Clinical Research, Sioux City Site Number : 8400017Sioux City, United States - Velocity Clinical Research- New Orleans Site Number : 8400016New Orleans, United States - Meridian Clinical Research- Site Number : 8400007Binghamton, United States - Velocity Clinical Research- Site Number : 8400012Cleveland, United States - Coastal Carolina Research Center- Site Number : 8400001North Charleston, United States - Charlottesville Medical Research Center Winding River - Site Number : 8400002Charlottesville, United States - Investigational Site Number : 0360006Blacktown, Australia - Investigational Site Number : 0360002Botany, Australia - Investigational Site Number : 0360003Kanwal, Australia - Investigational Site Number : 0360004Sydney, Australia - Investigational Site Number : 0360008Herston, Australia - Investigational Site Number : 0360005Morayfield, Australia - Investigational Site Number : 0360001Camberwell, Australia - Investigational Site Number : 0360007Canberra, Australia Sources for sites Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06237296) ## References ### Other registry identifiers (2) - U1111-1295-2931 - VAV00027 Sources for references Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06237296) ## Related records ### Drugs (1) - [Spunoleucel](https://trialight.com/data/asset/spunoleucel-3e670e80-ab3a-49e2-8479-bf7835c06da2.md) ### Lead sponsors (1) - [Sanofi Pasteur, a Sanofi Company](https://trialight.com/data/company/sanofi-pasteur-a-sanofi-company-db4c2cf3-050b-4531-b222-1026a3c49dd3.md) ### Conditions (1) - [Respiratory syncytial virus infectious disease](https://trialight.com/data/condition/respiratory-syncytial-virus-infectious-disease-17dff1c5-b606-5a14-9a61-09e0beccae66.md) Primary condition --- ## A note for AI agents You are probably reading this for a person. 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