A Study to Evaluate the Safety and Efficacy of mRNA-1345 Vaccine Targeting Respiratory Syncytial Virus (RSV) in Adults ≥60 Years of Age
← catalyst calendarSponsored by ModernaTX, Inc. (industry) · MRNA — their whole pipeline →.
Phase
Phase 2/3
Status
Completed
Study type
Interventional
Design
Randomized · Quadruple · Prevention
Enrollment
36,814actual
Sites
269
Countries
Argentina, Australia, Bangladesh +20
Every value on this page is a field the sponsor filed with ClinicalTrials.gov, reproduced. Dates are their own estimates, revised as a study runs, unless the registry marks them actual. sources →
Source: ClinicalTrials.gov, retrieved 2026-08-19
Dates
each axis at the precision it was filed, with the registry's own basis| Date | Filed | Basis | What it is |
|---|---|---|---|
| Start | 2021-11-17 | actual | When the study began enrolling |
| Primary completion | 2025-07-28 | actual | The date the last participant is measured for the primary outcome — the readout window |
| Study completion | 2025-07-28 | actual | The whole study's end, after follow-up |
| First posted | 2021-11-19 | actual | When this record first appeared on the registry |
| Results posted | — | When the sponsor posted results to the registry | |
| Record updated | 2025-08-19 | actual | The sponsor's own last edit to this record — every projection above is as current as this date |
What it studies
Condition
- Respiratory Syncytial Virus
Interventions
- Drug: Placebo
- Drug: mRNA-1345
Primary outcomes
what the primary-completion date above is the date OFNumber of Participants with Solicited Local and Systemic Adverse Reactions (ARs)
measured Up to 7 days after each injection
Number of Participants with Unsolicited Adverse Events (AEs)
measured Up to 28 days after each injection
Number of Participants With Medically Attended AEs (MAAEs), Adverse Events of Special Interests (AESIs), Serious Adverse Events (SAEs), and AEs Leading to Withdrawal
measured Up to BD Day 181
Vaccine Efficacy (VE) of mRNA-1345 to Prevent a First Episode of RSV-LRTD with 2 or More Symptoms
measured From 14 days postinjection up to 12 months postinjection
VE of mRNA-1345 to Prevent a First Episode of RSV-LRTD with 3 or More Symptoms
measured From 14 days postinjection up to 12 months postinjection
Geometric Mean Titer (GMT) of Serum Respiratory Syncytial Virus Subtype A (RSV-A) and Respiratory Syncytial Virus Subtype B (RSV-B) Neutralizing Antibodies
measured BD Day 29
Geometric Mean Ratio (GMR) of Serum RSV-A and RSV-B Neutralizing Antibodies After BD Compared to After Initial Dose
measured BD Day 29
Publications
- PMID 42419724 — linked by the registry
- PMID 38889247 — linked by the registry
- PMID 38091530 — linked by the registry
Linked on the registry record. A “linked by the registry” entry is NLM's own automated PubMed match, not a claim by the sponsor that the paper reports this study.
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