Recruiting

Vivotif & Vaxchora

Sponsor:

University of Maryland, Baltimore

Code:

NCT03705585

Conditions

Typhoid and/or Cholera Vaccination

Eligibility Criteria

Sex: All

Age: 18+

Healthy Volunteers: Accepted

Interventions

Vivotif Typhoid Oral Vaccine

Vaxchora

Study Details

Brief summary:

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

Group 1: Vivotif typhoid vaccination and/or Vaxchora cholera vaccination then endoscopy Group 2: Endoscopy, then Vivotif typhoid vaccination and/or Vaxchora cholera vaccination, then follow-up endoscopy Group 3: Endoscopy without vaccination.

Both vaccines used in this study are 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 and/or cholera vaccine.

Conditions

Typhoid and/or Cholera Vaccination

Study ID

NCT03705585

Start date

Nov 5, 2018

Status verified date

Sep, 2026

Completion date

May 31, 2029

Anticipated

Primary completion date

May 31, 2029

Anticipated

Eligibility Criteria

Eligibility Criteria

Sex: All

Age: 18+

Healthy Volunteers: Accepted

Inclusion Criteria:

  • 1\. Age 18 years and older
  • 2\. Already scheduled to undergo an EGD or colonoscopy for screening, surveillance, or a medically-indicated work-up at the University of Maryland Medical Center (main campus or Midtown)
  • 3\. Able to provide written informed consent prior to initiation of any study procedures
  • 4\. Healthy, as defined by considered fit to undergo outpatient elective EGD/colonoscopy by the evaluating health care provider

Exclusion Criteria:

  • 1\. Pregnancy or nursing mother
  • 2\. Known coagulopathy or bleeding disorder preventing mucosal biopsy
  • 3\. History of Crohn's disease or ulcerative colitis
  • 4\. For Subjects undergoing lower endoscopy (colonoscopy) only: Surgical removal of the ileocecal valve or any part of the small or large intestine (non-complicated appendectomy will be considered eligible)
  • 5\. Allergic reaction to oral typhoid or cholera vaccine in the past
  • 6\. Immunosuppression from illness or treatment, including

1. immune-deficiency disorders such as Human Immunodeficiency Virus (HIV) or Acquired Immunodeficiency Syndrome (AIDS)
2. leukemia, lymphoma, or cancers (localized non-melanoma skin cancers which are deemed inactive should be considered eligible)
  • 7\. Receipt of any other vaccine two weeks prior to receipt of Ty21a or CVD 103-HgR
  • 8\. Positive urine pregnancy test (HCG) prior to colonoscopy or vaccination

Study Design

Enrollment

240 participants

Anticipated

Allocation

Non randomized

Intervention Model

Parallel Assignment

Primary purpose

Basic Science

Interventions and Outcome Measures

Arms

experimental: Vaccination, Endoscopy

Individuals receive immunization with Vivotif typhoid vaccine and/or Vaxchora cholera vaccine prior to routine endoscopic examination. During endoscopy, small bowel biopsies will be obtained to examine immune responses and microbiota at the mucosal level; brushings might also be obtained.

experimental: Endoscopy, Vaccination, Endoscopy

Individuals receive immunization with Vivotif typhoid vaccine and/or Vaxchora cholera vaccine after initial endoscopic exam and specimen collection and prior to a routine follow up endoscopic examination during which additional specimens will be collected.

no intervention: Endoscopy Without Vaccination

Individuals do not receive immunization but consent to collection of specimens during endoscopy. The specimens to be collected in all three groups include stool, saliva, and small bowel biopsies (terminal ileum if colonoscopy performed, duodenum if EGD performed).

Interventions

Vivotif Typhoid Oral Vaccine

The 4 doses (1 capsule each) will be administered on alternate days, e.g., days 0, 2, 4, and 7 (± 1 day) under the supervision of the study coordinator(s).

Vaxchora

One dose. Approximately 100 mL of cool or room temperature purified bottled water is placed into a clean disposable cup. The contents of the buffer sachet are added to the water and stirred. Then the contents of the active (lyophilized vaccine) sachet are added to the water and stirred for approximately 30 seconds. The reconstituted mixture should be completely ingested within 15 minutes.

Primary outcome measure

  • Percentage of Responders [ Time Frame: approximately 5 years ]

Central Contacts and Locations

Central contacts

Rosary Zara Necesario, RN

410-706-6156rnecesario@som.umaryland.edu

Locations

University of Maryland, Baltimore, Center for Vaccine Development and Global Health

Recruiting

Baltimore, Maryland, United States, 21201

Contacts

Susan Holian, RN

susan.holian@som.umaryland.edu

More Information

Sponsor

University of Maryland, Baltimore

Last update posted

Sep 4, 2026

Last verified

Sep, 2026

Trial information was received from ClinicalTrials.gov and was last updated on 2026-09-10. This information was provided to ClinicalTrials.gov by University of Maryland, Baltimore on 2026-09-04.