Typhoid Vaccine for Gut Health

Overseen By Yuriko Adkins, PhD

Age: 18 - 65

Sex: Female

Trial Phase: Phase < 1

Sponsor: USDA, Western Human Nutrition Research Center

Must not be taking: Blood thinners, NSAIDs, Antibiotics, Immunosuppressants

Disqualifiers: HIV/AIDS, Cancer, Hypertension, Pregnancy, others

No Placebo Group All trial participants will receive the active study treatment (no placebo)

Approved in 2 Jurisdictions This treatment is already approved in other countries

Compensation: Varies

Number of Visits: 26

Duration: 4 weeks

What You Need to Know Before You Apply

What is the purpose of this trial?

This trial explores how an oral typhoid vaccine affects the gut and immune system. Researchers aim to determine if the vaccine can protect the intestinal barrier and measure changes in the body's immune response. All participants will receive the Vivotif Typhoid Oral Vaccine along with aspirin to assess these effects. Individuals with a BMI between 18.5 and 29.9 who have not had recent vaccines, typhoid exposure, or chronic conditions affecting their immune or digestive systems may be suitable candidates for this trial. As an Early Phase 1 trial, this research focuses on understanding how the treatment works in people, offering participants a chance to contribute to groundbreaking medical research.

Will I have to stop taking my current medications?

Yes, you may need to stop taking certain medications. The trial excludes people using blood thinners, anti-inflammatory drugs, antibiotics, anti-hypertensive drugs, anti-malaria drugs, and drugs that affect the immune system. If you're on any of these, you might need to stop them to participate.

Is there any evidence suggesting that this trial's treatments are likely to be safe?

Research shows that the Vivotif Typhoid Oral Vaccine is generally safe. In past studies, most participants did not experience serious side effects. The most common issues were mild, such as stomach pain, nausea, and headache, and these usually resolved on their own.

The FDA has approved the vaccine to prevent typhoid fever, confirming its safety for this purpose. Although it doesn't offer complete protection against typhoid, its safety is well-documented. While mild discomfort may occur, serious problems are rare. ^{1 2 3 4 5}

Why do researchers think this study treatment might be promising?

Unlike the standard typhoid vaccines, which are typically injected, the Vivotif Typhoid Oral Vaccine is taken by mouth. This oral delivery method makes it easier and more convenient for people to take, especially for those who might be uneasy about needles. Additionally, Vivotif is a live attenuated vaccine, which means it uses a weakened form of the typhoid bacteria to stimulate immunity. Researchers are excited about this approach because it could enhance gut health by directly targeting the gut, where the typhoid bacteria primarily cause infection.

What evidence suggests that the Vivotif Typhoid Oral Vaccine might be an effective treatment for gut health?

Research shows that the Vivotif Typhoid Oral Vaccine can protect adults and children over six from typhoid fever. Studies have found that the vaccine's effectiveness varies, with some studies showing protection for up to 78% of people. The vaccine might also affect the gut by altering immune responses, but this is still under investigation. This suggests the vaccine could do more than just prevent typhoid fever; it might also impact gut health and immune function. However, it is important to remember that while the vaccine is effective, it does not provide complete protection against typhoid fever. ^{1 3 6 7 8}

Who Is on the Research Team?

Danielle Lemay, PhD

Principal Investigator

USDA, ARS, Western Human Nutrition Research Center

Are You a Good Fit for This Trial?

This trial is for healthy adults with a BMI of 18.5-29.9 who haven't used antibiotics or been hospitalized recently, and don't have immune system diseases like HIV/AIDS, cancer, high blood pressure, or chronic illnesses. Pregnant women and those unwilling to use birth control or take an HIV test are excluded.

Inclusion Criteria

Your body mass index (BMI) is within the healthy range, which means you are not too underweight or overweight.

Exclusion Criteria

I take blood thinners every day.

I am currently undergoing cancer treatment with radiation or medication.

I am currently taking or have recently taken anti-malaria medication.

Timeline for a Trial Participant

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Baseline Measurement

Baseline gut permeability and immune response measurements are taken before vaccination

1 week

1 visit (in-person)

Treatment

Participants receive the Ty21a oral typhoid vaccine and aspirin, with gut permeability and immune response measured after each dose

4 weeks

Multiple visits on Day 1, 3, 16, 18, and 22

Follow-up

Participants are monitored for immune response and changes in gut permeability after the final vaccine dose

1 week

Visits on Day 24 and 29

What Are the Treatments Tested in This Trial?

Interventions

• Aspirin
• Vivotif Typhoid Oral Vaccine

Trial Overview

The study tests the impact of an oral typhoid vaccine on gut barrier function and immune response. Participants will undergo intestinal and whole-body assessments before and after receiving the vaccine compared to aspirin as a positive control.

How Is the Trial Designed?

Group I: Single group Experimental Treatment 2 Interventions

All participants will receive the vaccine and aspirin.

Vivotif Typhoid Oral Vaccine is already approved in United States for the following indications:

Approved in United States as Vivotif for:

• Immunization against disease caused by Salmonella typhi for travelers to areas where there is a recognized risk of exposure to S. typhi, persons with intimate exposure to an S. typhi carrier, and microbiology laboratorians who work frequently with S. typhi

Who Is Running the Clinical Trial?

USDA, Western Human Nutrition Research Center

Lead Sponsor

Trials

64

Recruited

19,100+

Citations

1.

fda.gov

fda.gov/media/75988/download

Vivotif® Typhoid Vaccine Live Oral Ty21a

Results from clinical studies indicate that adults and children greater than 6 years of age may be protected against typhoid fever following the oral ingestion ...

2.

vivotif.com

vivotif.com/

Vivotif: Live Typhoid Vaccine Administered Orally

Established Efficacy​​ Results from clinical studies indicate that adults and children greater than 6 years of age may be protected against typhoid fever ...

3.

pmc.ncbi.nlm.nih.gov

pmc.ncbi.nlm.nih.gov/articles/PMC3634757/

Impact of Oral Typhoid Vaccination on the Human Gut ...

The licensed oral live-attenuated typhoid vaccine Ty21a was administered in a clinical study to investigate whether oral immunization resulted in alterations ...

4.

pmc.ncbi.nlm.nih.gov

pmc.ncbi.nlm.nih.gov/articles/PMC5432773/

Overview of the impact of Typhoid and Paratyphoid fever. ...

Concerning the Ty21a vaccine (3-dose regimen), efficacy was 49% (95% CI: 16-70%), 60% (95% CI: 44-71%), 59% (95% CI: 32-75%), 78% (95% CI: 35-93%) and 47% (95% ...

5.

mayoclinic.org

mayoclinic.org/drugs-supplements/typhoid-vaccine-live-oral-route/description/drg-20066578

Typhoid vaccine, live (oral route) - Side effects & dosage

Typhoid vaccine taken by mouth helps prevent typhoid fever, but does not provide 100% protection.

6.

vivotif.com

vivotif.com/consumer/

Consumer & Patient Information | Vivotif® Oral Typhoid Vaccine

VIVOTIF is a prescription vaccine you take by mouth to help protect you from typhoid fever. 1 VIVOTIF is for adults and children greater than 6 years of age.

7.

vivotif.com

vivotif.com/faq/

Typhoid Fever and Vivotif® Frequently Asked Questions

Use and Important Safety Information for VIVOTIF® (vee-voh-TEEF). It is also known as Typhoid Vaccine, Live, Oral Ty21a. What is VIVOTIF used for?

8.

emergentbiosolutions.com

emergentbiosolutions.com/wp-content/uploads/2022/03/LBL040090.pdf

Vivotif®

Adverse drug reaction information from clinical trials is useful for identifying drug- related adverse events and for approximating rates.