Safety, Tolerability, and Immunogenicity of a 24-Valent Pneumococcal Conjugate Vaccine (VAX-24) in Healthy Infants
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Phase
Phase 2
Status
Completed
Study type
Interventional
Design
Randomized · Quadruple · Prevention
Enrollment
802actual
Sites
32
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 | 2023-03-29 | actual | When the study began enrolling |
| Primary completion | 2025-08-25 | actual | The date the last participant is measured for the primary outcome — the readout window |
| Study completion | 2025-08-25 | actual | The whole study's end, after follow-up |
| First posted | 2023-05-06 | actual | When this record first appeared on the registry |
| Results posted | — | When the sponsor posted results to the registry | |
| Record updated | 2025-09-11 | 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: 0.5 ml dose of 1.1 mcg VAX-24
- Biological: 0.5 ml dose of PCV20
- Biological: 0.5 ml dose of 2.2 mcg VAX-24
- Biological: 0.5 ml dose of 2.2/4.4 mcg VAX-24
Primary outcomes
what the primary-completion date above is the date OFPercentage of participants with any solicited local injection site Adverse Events (AE) within 7 days after each vaccination
measured 7 days after each vaccination
Percentage of participants with any solicited systemic AE within 7 days after each vaccination
measured 7 days after each vaccination
Percentage of participants with any related Serious Adverse Events (SAE) within 6 months after last vaccination
measured 6 months after last vaccination
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