A Study to Investigate The Safety, Tolerability, And Immune Response of a Range of Doses of mRNA-1769 Compared With Placebo in Healthy Participants From ≥18 Years of Age to <50 Years of Age
← catalyst calendarSponsored by ModernaTX, Inc. (industry) · MRNA — their whole pipeline →.
Phase
Phase 1/2
Status
Completed
Study type
Interventional
Design
Randomized · Quadruple · Prevention
Enrollment
351actual
Sites
12
Country
United Kingdom
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 | 2023-08-15 | actual | When the study began enrolling |
| Primary completion | 2025-07-08 | actual | The date the last participant is measured for the primary outcome — the readout window |
| Study completion | 2025-07-08 | actual | The whole study's end, after follow-up |
| First posted | 2023-08-16 | actual | When this record first appeared on the registry |
| Results posted | — | When the sponsor posted results to the registry | |
| Record updated | 2025-07-16 | actual | The sponsor's own last edit to this record — every projection above is as current as this date |
What it studies
Conditions
- Smallpox
- Mpox
Interventions
- Biological: mRNA-1769
- Other: Placebo
Primary outcomes
what the primary-completion date above is the date OFNumber of Solicited Local and Systemic Reactogenicity Adverse Reactions (ARs) Through 7 Days After Each Investigational Medicinal Product (IMP)
measured Up to Day 35
Number of Unsolicited Adverse Events (AEs) Through 7 Days After Each IMP
measured Up to Day 57
Number of Participants with Medically-Attended AEs (MAAEs)
measured Day 1 up to Day 395
Number of Participants with Adverse Events of Special Interest (AESIs)
measured Day 1 up to Day 395
Number of Participants with Serious Adverse Events (SAEs)
measured Day 1 up to Day 395
Number of Participants with AEs Leading to Study and/or Treatment Discontinuation
measured Day 1 up to Day 395
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