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NCT02561195 · ClinicalTrials.gov registry record · Phase 2

A Study To Investigate Two 3-dose Schedules Of A Clostridium Difficile Vaccine In Healthy Adults Aged 65 to 85 Years

A Phase 2 study, sponsored by Pfizer.

Completed
Registry status
Phase 2
Development phase
300
Enrollment target

NCT02561195: Completed Phase 2 study, sponsored by Pfizer.

NCT02561195 is a Phase 2 study that has completed, run by Pfizer. The registered enrollment target is 300 participants, above the 133-participant average among 30,622 other Phase 2 trials with a reported enrollment target (126% higher). According to ClinicalTrials.gov, the official US trial registry.

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The verdict

NCT02561195, a Phase 2 study, has completed, sponsored by Pfizer.

COMPLETED
Registry status
Phase 2
Development phase
300 participants
Enrollment target

Study Summary

This study will investigate a Clostridium difficile vaccine in healthy adults aged 65-85 years. Each subject will initially receive 3 doses of vaccine on 1 of 2 vaccination schedules. The study will assess the safety and tolerability of the vaccine as well as the subjects' immune response to the vaccine. One year after the third dose subjects that did not receive placebo will be randomized to receive a fourth dose. Subjects will be followed for up to 4 years after their third vaccination.

Primary Outcome

Toxin A antibodies (threshold \>= 219 neutralization units/mL) were measured using neutralization assay.

Interventions

  • BIOLOGICAL Placebo
  • BIOLOGICAL Clostridium difficile Vaccine

Trial Details

FieldValue
Enrollment Target 300 participants
Start Date 2015-07-16
Est. Completion 2020-02-13
Phase Phase 2
Pfizer

1,845 total trials

What the finished NCT02561195 record still lists

NCT02561195 is an interventional study that assigns participants to a tested intervention. The registered 300 participants enrollment target is mid-sized for trials with a published cap, above the 133-participant average among 30,622 other Phase 2 trials with a reported enrollment target (126% higher).

The record links to 0 conditions, and to 2 interventions - of which Placebo is the first listed.

NCT02561195 does not publish any study locations in the registry export this page uses.

Frequently Asked Questions

What is clinical trial NCT02561195 about?

NCT02561195 is a clinical study titled "A Study To Investigate Two 3-dose Schedules Of A Clostridium Difficile Vaccine In Healthy Adults Aged 65 to 85 Years". This study will investigate a Clostridium difficile vaccine in healthy adults aged 65-85 years. Each subject will initially receive 3 doses of vaccine on 1 of 2 vaccination schedules. The study will assess the safety and tolerability of the vaccine as well as the subjects' immune response to the vac...

What is the current status of trial NCT02561195?

This trial is currently completed. It is a Phase 2 study. The enrollment target is 300 participants. The study started on 2015-07-16. Estimated completion is 2020-02-13.

What interventions are being tested in trial NCT02561195?

The interventions under investigation include: Placebo (BIOLOGICAL), Clostridium difficile Vaccine (BIOLOGICAL).

Who is sponsoring clinical trial NCT02561195?

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 NCT02561195's enrollment target sits among peer trials

300 167th of 2000 higher than 1,813 of 2,000 other Phase 2 trials

participants (enrollment target), bucketed by value

Each bar is a band; taller bars hold more other Phase 2 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 NCT02561195, the US trial registry maintained by the National Library of Medicine. NCT02561195 (mid enrollment · none site footprint · completed) retrieved and formatted by PlainTrial, see methodology.