Safety, Tolerability, and Immunogenicity of VAX-31 in Adults ≥50 Years With Prior Pneumococcal Vaccination
← catalyst calendarNCT07425392 · readout ≤ 224 d
Sponsored by Vaxcyte, Inc. (industry) · PCVX — their whole pipeline →.
Phase
Phase 3
Status
Active, not recruiting
Study type
Interventional
Design
Randomized · Quadruple · Prevention
Enrollment
752actual
Sites
30
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 | 2026-02-09 | actual | When the study began enrolling |
| Primary completion | Mar 2027 | estimated | The date the last participant is measured for the primary outcome — the readout window |
| Study completion | Mar 2027 | estimated | The whole study's end, after follow-up |
| First posted | 2026-02-20 | actual | When this record first appeared on the registry |
| Results posted | — | When the sponsor posted results to the registry | |
| Record updated | 2026-06-30 | actual | The sponsor's own last edit to this record — every projection above is as current as this date |
What it studies
Condition
- Pneumococcal Vaccines
Interventions
- Biological: 31-valent pneumococcal conjugate vaccine
- Biological: PCV20
Primary outcomes
what the primary-completion date above is the date OFSerotype-specific OPA geometric mean titers (GMT)
measured 1 month after VAX-31 vaccination
Serotype-specific OPA geometric mean fold rise (GMFR) from baseline
measured 1 month after VAX-31 vaccination
Percentage of subjects reporting solicited local adverse events (AE) (redness, swelling, and pain at injection site)
measured up to 7 days after vaccination
Percentage of subjects reporting solicited systemic AE (fever, headache, fatigue, muscle pain, and joint pain)
measured up to 7 days after vaccination
Percentage of subjects reporting unsolicited AE
measured up to 31 days after vaccination
Percentage of subjects reporting new onset of chronic illness (NOCI), medically attended AE (MAAE), and serious adverse events (SAE)
measured up to 6 months after vaccination
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