Study of an RSV-hMPV-PIV3 Trivalent Vaccine Candidate VXB-251 in Older Adults
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Phase
Phase 1
Status
Active, not recruiting
Study type
Interventional
Design
Randomized · Double · Prevention
Enrollment
240actual
Sites
6
Country
Australia
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 | 2025-11-17 | actual | When the study began enrolling |
| Primary completion | 2026-04-21 | actual | The date the last participant is measured for the primary outcome — the readout window |
| Study completion | 2027-04-24 | estimated | The whole study's end, after follow-up |
| First posted | 2025-12-19 | actual | When this record first appeared on the registry |
| Results posted | — | When the sponsor posted results to the registry | |
| Record updated | 2026-05-20 | actual | The sponsor's own last edit to this record — every projection above is as current as this date |
What it studies
Conditions
- Lower Respiratory Tract Disease
- Healthy Participants
Interventions
- Biological: trivalent (RSV/hMPV/PIV3) vaccine candidate
- Biological: trivalent (RSV/hMPV/PIV3) vaccine candidate
- Biological: trivalent (RSV/hMPV/PIV3) vaccine candidate
- Biological: bivalent (RSV/hMPV) unlicensed comparator
- Biological: monovalent (RSV) unlicensed comparator
- Biological: Biological/Vaccine: monovalent (hMPV) unlicensed comparator
- Biological: monovalent (PIV3) unlicensed comparator
- Other: Placebo
Primary outcomes
what the primary-completion date above is the date OFProportion of Participants With 1 or More Unsolicited Adverse Events (AEs)
measured 1 month after IMP injection
Proportion of Participants With 1 or More Serious Adverse Events (SAEs), AEs of Special Interest (AESIs), and Premature Discontinuation Associated AEs (PDAEs)
measured 1 month after IMP injection
Proportion of Participants With 1 or More Solicited AEs
measured 7 days after IMP injection
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