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NCT05266456 · ClinicalTrials.gov registry record · Phase 1
Safety, Tolerability, and Immunogenicity Study of a 24-Valent Pneumococcal Conjugate Vaccine (VAX-24) in Adults
A Phase 1 study, sponsored by Vaxcyte.
- Completed
- Registry status
- Phase 1
- Development phase
- 835
- Enrollment target
NCT05266456: Completed Phase 1 study, sponsored by Vaxcyte.
NCT05266456 is a Phase 1 study that has completed, run by Vaxcyte. The registered enrollment target is 835 participants, above the 60-participant average among 29,502 other Phase 1 trials with a reported enrollment target (1292% higher). According to ClinicalTrials.gov, the official US trial registry.
The verdict
NCT05266456, a Phase 1 study, has completed, sponsored by Vaxcyte.
- COMPLETED
- Registry status
- Phase 1
- Development phase
- 835 participants
- Enrollment target
Study Summary
The objective of the study is to evaluate the safety and tolerability of a single injection of VAX-24 at 3 dose levels compared to Prevnar 20™ (PCV20) in adults 18 to 49 years of age in Phase 1. The Phase 2 will evaluate the safety, tolerability, and immunogenicity of a single injection of VAX-24 at 3 dose levels compared to PCV20 in adults aged 50 to 64 years of age in Phase 2.
Primary Outcome
Solicited local reactions include redness/erythema, swelling/induration, and pain at injection site within 7 days after vaccination in each age group
Interventions
- BIOLOGICAL 20 valent pneumococcal conjugate vaccine
- BIOLOGICAL 24 valent pneumococcal conjugate vaccine
Trial Details
| Field | Value |
|---|---|
| Enrollment Target | 835 participants |
| Start Date | 2022-02-22 |
| Est. Completion | 2023-01-10 |
| Phase | Phase 1 |
What the finished NCT05266456 record still lists
NCT05266456 is an interventional study that assigns participants to a tested intervention. The registered 835 participants enrollment target is mid-sized for trials with a published cap, above the 60-participant average among 29,502 other Phase 1 trials with a reported enrollment target (1292% higher).
The record links to 0 conditions, and to 2 interventions - of which 20 valent pneumococcal conjugate vaccine is the first listed.
NCT05266456 does not publish any study locations in the registry export this page uses.
Frequently Asked Questions
What is clinical trial NCT05266456 about?
NCT05266456 is a clinical study titled "Safety, Tolerability, and Immunogenicity Study of a 24-Valent Pneumococcal Conjugate Vaccine (VAX-24) in Adults". The objective of the study is to evaluate the safety and tolerability of a single injection of VAX-24 at 3 dose levels compared to Prevnar 20™ (PCV20) in adults 18 to 49 years of age in Phase 1. The Phase 2 will evaluate the safety, tolerability, and immunogenicity of a single injection of VAX-24 at...
What is the current status of trial NCT05266456?
This trial is currently completed. It is a Phase 1 study. The enrollment target is 835 participants. The study started on 2022-02-22. Estimated completion is 2023-01-10.
What interventions are being tested in trial NCT05266456?
The interventions under investigation include: 20 valent pneumococcal conjugate vaccine (BIOLOGICAL), 24 valent pneumococcal conjugate vaccine (BIOLOGICAL).
Who is sponsoring clinical trial NCT05266456?
This trial is sponsored by Vaxcyte, which has 8 total clinical trials registered on ClinicalTrials.gov.
Learn More About Clinical Trials
How this trial's enrollment target compares
Where NCT05266456's enrollment target sits among peer trials
835 12th of 2000 higher than 1,989 of 2,000 other Phase 1 trials
participants (enrollment target), bucketed by value
Each bar is a band; taller bars hold more other Phase 1 trials. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count and share, and where it sits relative to this entry.
Source ClinicalTrials.gov registry export · 2026-08-08
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