A Study to Learn About the Safety and Immune Response of a New Pneumococcal Vaccine in Adults
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Phase
Phase 1/2
Status
Completed
Study type
Interventional
Design
Randomized · Triple · Prevention
Enrollment
1,363actual
Sites
20
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 | 2023-12-20 | actual | When the study began enrolling |
| Primary completion | 2026-05-12 | actual | The date the last participant is measured for the primary outcome — the readout window |
| Study completion | 2026-05-12 | actual | The whole study's end, after follow-up |
| First posted | 2023-12-26 | actual | When this record first appeared on the registry |
| Results posted | — | When the sponsor posted results to the registry | |
| Record updated | 2026-06-10 | actual | The sponsor's own last edit to this record — every projection above is as current as this date |
What it studies
Condition
- Pneumococcal Disease
Interventions
- Biological: Multivalent Pneumococcal Vaccine - Formulation 1
- Biological: Multivalent Pneumococcal Vaccine - Formulation 2
- Biological: 20-valent pneumococcal conjugate vaccine (20vPnC) — also filed as Prevnar 20
- Biological: Licensed pneumococcal comparator vaccine
- Biological: Multivalent Pneumococcal Vaccine - Formulation 3
- Biological: Multivalent Pneumococcal Vaccine - Formulation 4
Primary outcomes
what the primary-completion date above is the date OFPercentage of participants reporting prespecified local reactions within 7 days after vaccination
measured 7 days
Percentage of participants reporting prespecified systemic events within 7 days after vaccination
measured 7 days
Percentage of participants reporting Adverse Events (AEs) within 1 month after vaccination
measured 1 month
Percentage of participants reporting Serious Adverse Events (SAEs) within 6 months after vaccination
measured 6 months
Phase 2 (Stage 2) Only: Percentage of participants reporting related Serious Adverse Events (SAEs) through 12 months after vaccination
measured 12 months
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