CVD 37000: Immunity and Microbiome Studies At Intestinal and Systemic Sites in Ty21a Vaccinated Adults

Phase 4

Active, not recruiting

• Conditions: Typhoid Vaccination
• Interventions: Drug: Vivotif Typhoid Oral Vaccine

• Registration Number: NCT03970304
• Lead Sponsor: University of Maryland, Baltimore

Brief Summary

This is an open-label, non-randomized study. The purpose of this study is to better understand how vaccines against typhoid fever affect the normal immune system and bacteria in the intestine. Patients having standard-of-care colonoscopies will be divided into 3 groups:

Group 1: Vivotif typhoid vaccination then colonoscopy; Group 2: Colonoscopy, then Vivotif typhoid vaccination, then follow-up colonoscopy; Group 3: Colonoscopy without vaccination.

The Vivotif typhoid vaccine used in this study is licensed by the Food and Drug Administration (FDA) for travelers to developing countries. Volunteers will be asked to donate tissue, blood, saliva and stool samples for studying how the body responds to the typhoid vaccine.

Detailed Description

Not available

Study Timeline

• Study Start: 2013-10-24
• Study First Submitted: 2019-05-29
• Study First Submitted QC: 2019-05-29
• Study First Posted: 2019-05-31
• Status Verified: 2024-12
• Last Update Submitted: 2024-12-03
• Last Update Posted: 2024-12-06
• Primary Completion: 2027-08-01
• Study Completion: 2027-08-01

Recruitment & Eligibility

• Status: ACTIVE_NOT_RECRUITING
• Sex: All
• Target Recruitment: 87

Inclusion Criteria

• Age 18 years and older
• Undergoing colonoscopy for screening or surveillance for colorectal cancer at the University of Maryland
• Provide written informed consent prior to initiation of any study procedures
• Healthy, as defined by considered fit to undergo outpatient elective colonoscopy by the referring health care provider

Exclusion Criteria

• Pregnancy or nursing mother

• Known coagulopathy or bleeding disorder preventing mucosal biopsy

• History of Crohn's disease or ulcerative colitis

• Surgical removal of the ileocecal valve or any part of the small or large intestine

• Allergic reaction to oral typhoid vaccine in the past

• Immunosuppression from illness or treatment, including

  • immune-deficiency disorders such as Human Immunodeficiency Virus (HIV) or Acquired Immunodeficiency Syndrome (AIDS)
  • leukemia, lymphoma, or cancers
  • immune suppressive medications or treatments, such as corticosteroids or radiation

• Receipt of any other vaccine two weeks prior to receipt of Ty21a

• Positive urine pregnancy test (HCG) prior to colonoscopy or vaccination

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Vaccination, Colonoscopy	Vivotif Typhoid Oral Vaccine	Individuals receive immunization with Vivotif typhoid vaccine prior to routine colonoscopy examination. During colonoscopy, small bowel biopsies will be obtained to examine immune responses and microbiota at the mucosal level; brushings will also be obtained.
Colonoscopy, Vacciniation, Colonoscopy	Vivotif Typhoid Oral Vaccine	Individuals receive immunization with Vivotif typhoid vaccine after initial colonoscopy exam and specimen collection and prior to a routine follow up colonoscopy examination during which additional specimens will be collected.

Primary Outcome Measures

Name	Time	Method
Percentage of Responders	approximately 5 years	Percentage of responders by cytokine production (Interferon-gamma (IFN-gamma) or Tumor Necrosis Factor-alpha (TNF-α)) by mass cytometry or flow cytometry. Responders will be defined as those volunteers showing increases post-immunization of \>0.1% of positive CD8+ cells for IFN-gamma or TNF-α over baseline (pre-immunization) values.) or Tumor Necrosis Factor-alpha (TNF-α)) by mass cytometry or flow cytometry.

Trial Locations

Locations (1)

Universtiy of Maryland, Baltimore, Center for Vaccine Development and Global Health; 🇺🇸 Baltimore, Maryland, United States