ClinicalTrials.gov record
Active, not recruiting Phase 1Phase 2 Interventional Accepts healthy volunteers

To Understand the Safety and Effects of a C. Difficile Vaccine With New Adds-Ons That Will Be Given to Healthy Adults

ClinicalTrials.gov ID: NCT05805826

Public ClinicalTrials.gov record NCT05805826. Field values are reproduced from the official study page; the official ClinicalTrials.gov record remains the source of truth for eligibility, enrollment, and contact information.

ClinicalTrials.gov public records Last synced May 20, 2026, 12:31 AM EDT

Data is sourced from official ClinicalTrials.gov public API records. Always review the official ClinicalTrials.gov record for the latest information.

Official title

A PHASE 1/2 RANDOMIZED STUDY TO EVALUATE THE SAFETY, TOLERABILITY, IMMUNOGENICITY, AND IMMUNOPERSISTENCE OF A CLOSTRIDIOIDES DIFFICILE VACCINE ADMINISTERED WITH NOVEL ADJUVANTS IN HEALTHY ADULTS

Study identification

NCT ID
NCT05805826
Recruitment status
Active, not recruiting
Study type
Interventional
Phase
Phase 1, Phase 2
Lead sponsor
Pfizer
Industry
Enrollment
936 participants

Conditions and interventions

Interventions

  • C. difficile vaccine (previously studied formulation). Biological
  • C. difficile vaccine formulation 1. Biological
  • C. difficile vaccine formulation 2. Biological
  • C. difficile vaccine formulation 3. Biological
  • Saline Placebo. Other

Biological · Other

Eligibility (public fields only)

Age range
50 Years and older
Sex
All
Healthy volunteers
Accepts healthy volunteers

This page does not interpret eligibility. Detailed inclusion and exclusion criteria are on the official ClinicalTrials.gov record.

Study timeline

Start date
Mar 22, 2023
Primary completion
Jun 18, 2031
Completion
Jun 18, 2031
Last update posted
Apr 28, 2026

2023 – 2031

United States locations

U.S. sites
23
U.S. states
11
U.S. cities
20
Facility City State ZIP Site status
HOPE Research Institute Phoenix Arizona 85032
Anaheim Clinical Trials, LLC Anaheim California 92801
Alliance for Multispecialty Research, LLC Doral Florida 33172
Indago Research & Health Center, Inc Hialeah Florida 33012
Research Centers of America Hollywood Florida 33024
Miami Clinical Research Miami Florida 33155
New Horizon Research Center Miami Florida 33165
Charisma Medical and Research Center Miami Lakes Florida 33014
Private Practice - Dr. Hector Fabregas Pembroke Pines Florida 33026
DBC Research USA Pembroke Pines Florida 33029
BRCR Medical Center Inc. Plantation Florida 33322
Clinical Research Trials of Florida Tampa Florida 33607
Great Lakes Clinical Trials - Ravenswood Chicago Illinois 60640
Alliance for Multispecialty Research, LLC Wichita Kansas 67226
Prism Research LLC dba Nucleus Network Saint Paul Minnesota 55114
Washington University School of Medicine St Louis Missouri 63110
Washington University St Louis Missouri 63130
NYU Langone Health New York New York 10016
Rochester Clinical Research, Inc. Rochester New York 14609
Qcare Site Services Inc. d/b/a Avacare Durham North Carolina 27703
CTI Clinical Research Center Cincinnati Ohio 45212
Benchmark Research Austin Texas 78705
Dynamed Clinical Research, LP d/b/a DM Clinical Research Tomball Texas 77375

Site contact phone numbers, emails, and investigator names are intentionally not displayed here. Open the official ClinicalTrials.gov record for site contact information.

About this trial record page

What this page shows
Public field values for ClinicalTrials.gov record NCT05805826, including study identification, conditions, interventions, eligibility (age, sex, healthy volunteer), timeline, and U.S. site list.
What this page does not do
No medical advice, eligibility judgments, treatment recommendations, study quality scoring, or AI-generated medical summaries. No site contact phone numbers, emails, or investigator names.
Where the data comes from
Sourced from the official ClinicalTrials.gov public API. The official record is the source of truth.
Last refresh
Last update posted Apr 28, 2026 · Synced May 20, 2026

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Open the official record

The complete protocol, eligibility criteria, and contact information for NCT05805826 live on ClinicalTrials.gov.

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