Phase 3 Randomized, Modified Double-blind, Active-controlled Safety Study on vYF in Adults
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Phase
Phase 3
Status
Completed
Study type
Interventional
Design
Randomized · Quadruple · Prevention
Enrollment
640actual
Sites
7
Country
United States
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 | 2025-05-22 | actual | When the study began enrolling |
| Primary completion | 2026-01-20 | actual | The date the last participant is measured for the primary outcome — the readout window |
| Study completion | 2026-01-20 | actual | The whole study's end, after follow-up |
| First posted | 2025-06-03 | actual | When this record first appeared on the registry |
| Results posted | — | When the sponsor posted results to the registry | |
| Record updated | 2026-02-02 | actual | The sponsor's own last edit to this record — every projection above is as current as this date |
What it studies
Condition
- Yellow Fever Immunization
Interventions
- Biological: Yellow fever vaccine (live) — also filed as vYF vaccine
- Biological: YF vaccine (live) — also filed as YF-VAX vaccine, YF-VAX
Primary outcomes
what the primary-completion date above is the date OFNumber of participants with immediate adverse events
measured Within 30 minutes after vaccination
Number of participants with solicited injection site reactions
measured Up to 7 days after vaccination
Number of participants with solicited systemic reactions
measured Up to 14 days after vaccination
Number of participants with unsolicited adverse events (AEs)
measured Up to 28 days after vaccination
Number of participants with medical attended adverse events (MAAEs)
measured Up to 28 days after vaccination
Number of participants with adverse events of special interest (AESIs)
measured Up to 6 months after vaccination
Number of participants with serious adverse events (SAEs)
measured Up to 6 months after vaccination
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