A Study to Investigate the Immunogenicity and Safety of mRNA-1345 Vaccine Targeting Respiratory Syncytial Virus (RSV) in High-risk Adults
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Phase
Phase 3
Status
Active, not recruiting
Study type
Interventional
Design
Randomized · Quadruple · Prevention
Enrollment
1,153actual
Sites
44
Countries
Canada, Puerto Rico, United Kingdom +1
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 | 2023-10-06 | actual | When the study began enrolling |
| Primary completion | 2026-07-30 | estimated | The date the last participant is measured for the primary outcome — the readout window |
| Study completion | 2026-07-30 | estimated | The whole study's end, after follow-up |
| First posted | 2023-10-04 | actual | When this record first appeared on the registry |
| Results posted | — | When the sponsor posted results to the registry | |
| Record updated | 2025-08-08 | 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
Intervention
- Biological: 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 Day 1 through Day 7 (7 days post injection) for Part A and Day 1 through Day 64 (7 days post second injection) for Part B
Number of Participants with Unsolicited Adverse Events (AEs)
measured Day 1 through Day 28 (28 days post injection) for Part A and Day 1 through Day 84 (28 days post second injection) for Part B
Number of Participants With Medically Attended AEs (MAAEs)
measured Day 1 through Month 6 (for Part A) and Day 1 through Month 9 (for Part B)
Number of Participants With Serious Adverse Events (SAEs), Adverse Events of Special Interest (AESIs), and AEs Leading to Discontinuation
measured Day 1 through End of Study (Day 730)
Part A: Geometric Mean Titer (GMT) of Serum Respiratory Syncytial Virus Subtype A (RSV-A) and Respiratory Syncytial Virus Subtype B (RSV-B) Neutralizing Antibodies (Abs) at Day 29
measured Day 29
Part B: GMT of Serum RSV-A and RSV-B Neutralizing Abs at Day 85
measured Day 85
Publications
- PMID 41711453 — linked by the registry
- PMID 40464662 — 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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