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NCT04526574 · ClinicalTrials.gov registry record · Phase 3

Safety and Immunogenicity of 20vPnC Coadministered With SIIV in Adults ≥65 Years of Age

A Phase 3 study, sponsored by Pfizer.

Completed
Registry status
Phase 3
Development phase
1,796
Enrollment target

NCT04526574: Completed Phase 3 study, sponsored by Pfizer.

NCT04526574 is a Phase 3 study that has completed, run by Pfizer. The registered enrollment target is 1,796 participants, above the 772-participant average among 15,282 other Phase 3 trials with a reported enrollment target (133% higher). According to ClinicalTrials.gov, the official US trial registry.

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The verdict

NCT04526574, a Phase 3 study, has completed, sponsored by Pfizer.

COMPLETED
Registry status
Phase 3
Development phase
1,796 participants
Enrollment target

Study Summary

Study of the safety and immunogenicity of 20vPnC and influenza vaccine administered at the same visit or separately

Primary Outcome

Local reactions were collected at the 20vPnC injection sites after Vaccination 1 and Vaccination 2 and were recorded by the participants using an electronic diary (e-diary). Local reactions included redness, swelling and pain at the injection site. Redness and swelling were measured and recorded in measuring device units. 1 measuring device unit =0.5 centimeter (cm). Redness and swelling were graded as mild (greater than \[\>\] 2.0 to 5.0 cm), moderate (\>5.0 to 10.0 cm) and severe (\>10.0 cm).

Interventions

  • OTHER Saline
  • BIOLOGICAL Influenza vaccine
  • BIOLOGICAL Experimental 20-valent pneumococcal conjugate vaccine (20vPnC)

Trial Details

FieldValue
Enrollment Target 1,796 participants
Start Date 2020-09-01
Est. Completion 2021-06-29
Phase Phase 3
Pfizer

1,845 total trials

What the finished NCT04526574 record still lists

NCT04526574 is an interventional study that assigns participants to a tested intervention. Its 1,796 participants enrollment target places it among the larger protocols in the corpus, above the 772-participant average among 15,282 other Phase 3 trials with a reported enrollment target (133% higher).

The record links to 0 conditions, and to 3 interventions - of which Saline is the first listed.

NCT04526574 does not publish any study locations in the registry export this page uses.

Frequently Asked Questions

What is clinical trial NCT04526574 about?

NCT04526574 is a clinical study titled "Safety and Immunogenicity of 20vPnC Coadministered With SIIV in Adults ≥65 Years of Age". Study of the safety and immunogenicity of 20vPnC and influenza vaccine administered at the same visit or separately

What is the current status of trial NCT04526574?

This trial is currently completed. It is a Phase 3 study. The enrollment target is 1,796 participants. The study started on 2020-09-01. Estimated completion is 2021-06-29.

What interventions are being tested in trial NCT04526574?

The interventions under investigation include: Saline (OTHER), Influenza vaccine (BIOLOGICAL), Experimental 20-valent pneumococcal conjugate vaccine (20vPnC) (BIOLOGICAL).

Who is sponsoring clinical trial NCT04526574?

This trial is sponsored by Pfizer, which has 1,845 total clinical trials registered on ClinicalTrials.gov.

How this trial's enrollment target compares

Where NCT04526574's enrollment target sits among peer trials

1,796 125th of 2000 higher than 1,876 of 2,000 other Phase 3 trials

participants (enrollment target), bucketed by value

Each bar is a band; taller bars hold more other Phase 3 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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Source: ClinicalTrials.gov NCT04526574, the US trial registry maintained by the National Library of Medicine. NCT04526574 (large enrollment · none site footprint · completed) retrieved and formatted by PlainTrial, see methodology.