Active — Not RecruitingPhase 1/2

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

United States1,530 participantsStarted 2024-11-11

Plain-language 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

Who can participate

Age range

60 Years

Sex

ALL

See this in plain English?

AI-rewrites the medical criteria so a patient or caregiver can understand them. Always confirm with the trial site.

Inclusion Criteria: * Aged 60 years or older on the day of inclusion * A female participant is eligible to participate if she is not pregnant or breastfeeding and is of non-childbearing potential. To be considered of non-childbearing potential, a female must be postmenopausal for at least 1 year or surgically sterile Exclusion Criteria: * Any screening laboratory parameter with laboratory abnormality \> Grade 1 deemed clinically significant by the investigator * Known or suspected congenital or acquired immunodeficiency; or receipt of immunosuppressive therapy, such as anti-cancer chemotherapy or radiation therapy, within the preceding 6 months; or long-term systemic corticosteroid therapy (prednisone or equivalent for more than 2 consecutive weeks within the past 3 months). Of note, persons living with stable human immunodeficiency virus (HIV) are not excluded * Known systemic hypersensitivity to any of the study intervention components (eg, polyethylene glycol, polysorbate); history of a life-threatening reaction to the study interventions used in the study or to a product containing any of the same substances; any allergic reaction (eg, anaphylaxis) after administration of an mRNA vaccine * History of RSV and/or hMPV-associated illness, diagnosed serologically or microbiologically in the last 12 months * Previous history of myocarditis, pericarditis, and/or myopericarditis * Screening electrocardiogram that is consistent with possible myocarditis, pericarditis, and/or m…

Questions worth asking your doctor

Bring these to your next appointment. They're a starting point for a shared conversation — not a sign you qualify or a recommendation to enrol.

1Based on my diagnosis and history, is this trial worth exploring for me — or is there a standard treatment we should try first?
2What does this trial's phase tell us about how much is already known about its safety and benefit?
3What would taking part actually involve for me — visits, tests, time, and travel?
4What are the known and possible risks or side effects I should weigh, and how would they be monitored?
5If this trial isn't the right fit, what other options or trials would you suggest I look into?

Generated to help you prepare — always confirm anything about your own eligibility and care with the study team and your doctor.

Questions for the trial coordinator

The trial coordinator is the person who runs the study day to day. These cover the practical side — logistics, costs, and what taking part would actually mean for your life. The study team confirms whether you meet the criteria; these are questions to ask, not a sign you qualify.

1What does taking part actually involve week to week — how many visits, where, and how long does each one take?
2What costs are covered by the study, and what might I have to pay for myself, including travel, parking, or time off work?
3What happens during screening, and what happens if the study team confirms I don't meet the criteria after those tests?
4Who pays for the scans, blood work, and other tests the trial requires — the study, my insurance, or me?
5How will being in the trial affect my regular care, and will my own doctor stay informed and involved?
6Can I leave the trial at any point if I change my mind, and what would happen to my care if I do?

A starting point for the conversation — always confirm anything about your own eligibility, costs, and care with the study team and your doctor.

What they're measuring

Presence of unsolicited immediate systemic adverse events (AEs) (Stage 1 and Stage 2 Expansion and Booster Cohorts)

Timeframe: Within 30 minutes after primary and booster vaccinations

Presence of solicited injection site and systemic reactions (Stage 1 and Stage 2 Expansion and Booster Cohorts)

Timeframe: Up to 7 days after primary and booster vaccinations

Presence of unsolicited AEs (Stage 1 and Stage 2 Expansion and Booster Cohorts)

Timeframe: Up to 28 days after primary and booster vaccinations

Presence of medically attended AEs (MAAEs) (Stage 1 and Stage 2 Expansion and Booster Cohorts)

Timeframe: Up to 6 months after primary and booster vaccinations

Presence of serious AEs (SAEs) and AEs of special interest (AESIs) (Stage 1 and Stage 2 Expansion and Booster Cohorts)

Timeframe: Up to 6 months after primary and booster vaccinations

Presence of related SAEs, related AESIs, and fatal SAEs (regardless of causality) (Stage 1 and Stage 2 Expansion and Booster Cohorts)

Timeframe: Throughout the duration of the study (up to approximately 24 months)

Trial details

NCT IDNCT06686654

SponsorSanofi Pasteur, a Sanofi Company

Sponsor typeINDUSTRY

Study typeINTERVENTIONAL

Primary completion2027-01-18

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