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NCT03835975 · ClinicalTrials.gov registry record · Phase 3
Trial to Evaluate the Safety and Immunogenicity of a 20-Valent Pneumococcal Vaccine in Adults 65 Years of Age or Older With Prior Pneumococcal Vaccination
A Phase 3 study, sponsored by Pfizer.
- Completed
- Registry status
- Phase 3
- Development phase
- 875
- Enrollment target
NCT03835975: Completed Phase 3 study, sponsored by Pfizer.
NCT03835975 is a Phase 3 study that has completed, run by Pfizer. The registered enrollment target is 875 participants, above the 772-participant average among 15,282 other Phase 3 trials with a reported enrollment target (13% higher). According to ClinicalTrials.gov, the official US trial registry.
The verdict
NCT03835975, a Phase 3 study, has completed, sponsored by Pfizer.
- COMPLETED
- Registry status
- Phase 3
- Development phase
- 875 participants
- Enrollment target
Study Summary
This Phase 3 will describe the safety and immunogenicity of a 20-valent pneumococcal conjugate vaccine formulation in adults 65 years of age or older with prior pneumococcal vaccination
Primary Outcome
Local reactions were recorded 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). Pain at injection site was graded as mild (did not interfere with activity), moderate (interfered with acti
Interventions
- BIOLOGICAL 13vPnC
- BIOLOGICAL PPSV23
- BIOLOGICAL 20vPnC
Trial Details
| Field | Value |
|---|---|
| Enrollment Target | 875 participants |
| Start Date | 2019-02-12 |
| Est. Completion | 2020-02-12 |
| Phase | Phase 3 |
What the finished NCT03835975 record still lists
NCT03835975 is an interventional study that assigns participants to a tested intervention. The registered 875 participants enrollment target is mid-sized for trials with a published cap, above the 772-participant average among 15,282 other Phase 3 trials with a reported enrollment target (13% higher).
The record links to 0 conditions, and to 3 interventions - of which 13vPnC is the first listed.
NCT03835975 does not publish any study locations in the registry export this page uses.
Frequently Asked Questions
What is clinical trial NCT03835975 about?
NCT03835975 is a clinical study titled "Trial to Evaluate the Safety and Immunogenicity of a 20-Valent Pneumococcal Vaccine in Adults 65 Years of Age or Older With Prior Pneumococcal Vaccination". This Phase 3 will describe the safety and immunogenicity of a 20-valent pneumococcal conjugate vaccine formulation in adults 65 years of age or older with prior pneumococcal vaccination
What is the current status of trial NCT03835975?
This trial is currently completed. It is a Phase 3 study. The enrollment target is 875 participants. The study started on 2019-02-12. Estimated completion is 2020-02-12.
What interventions are being tested in trial NCT03835975?
The interventions under investigation include: 13vPnC (BIOLOGICAL), PPSV23 (BIOLOGICAL), 20vPnC (BIOLOGICAL).
Who is sponsoring clinical trial NCT03835975?
This trial is sponsored by Pfizer, which has 1,845 total clinical trials registered on ClinicalTrials.gov.
Learn More About Clinical Trials
How this trial's enrollment target compares
Where NCT03835975's enrollment target sits among peer trials
875 372nd of 2000 higher than 1,629 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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