Vaccination with the typhoid oral vaccine Vivotif for blood donors
Collection of Blood Samples for In-Vitro Studies From Healthy Adult Blood Donors Who Have Received Oral Typhoid Vaccine (TY21A)
This study is testing the typhoid oral vaccine Vivotif in blood donors to see how it helps protect against typhoid fever and understand the immune response over time.
Quick facts
| Phase | Phase 4 |
|---|---|
| Study type | Interventional |
| Enrollment | 150 (estimated) |
| Ages | 18 Years and up |
| Sex | All |
| Sponsor | University of Maryland, Baltimore Academic / other |
| Locations | 1 site (Baltimore, Maryland) |
| Trial ID | NCT03971669 on ClinicalTrials.gov |
What this trial studies
This open-label, non-randomized study involves volunteers receiving the typhoid oral vaccine, Vivotif, which is FDA-approved for travelers to developing countries. Participants will provide blood, saliva, and stool specimens over a follow-up period of up to eight years. The collected specimens will help researchers understand the immunological mechanisms that provide protection against typhoid and may be applicable to other enteric pathogens. The study aims to enhance knowledge about risk reduction for typhoid fever.
Who should consider this trial
Good fit: Ideal candidates are healthy adults aged 18 years and older who can provide informed consent.
Not a fit: Patients with a history of significant medical conditions such as heart disease, diabetes, or recurrent infections may not benefit from this study.
Why it matters
Potential benefit: If successful, this study could improve understanding of immune responses to typhoid vaccination, potentially leading to better prevention strategies for enteric diseases.
How similar studies have performed: Other studies have shown success with similar vaccination approaches, but this specific study focuses on a novel application of the Vivotif vaccine.
Eligibility criteria
Show full inclusion / exclusion criteria
Inclusion Criteria: * Age 18 years and older * Good general health as determined by a screening evaluation within 28 days before blood donation * Informed, written consent Exclusion Criteria: * History of any of the following medical illnesses: * Diabetes * Cancer in past 5 years (except for basal cell carcinoma of the skin and cervical carcinoma in situ) * Heart disease (Hospitalization for a heart attack, coronary artery bypass graft, arrhythmia, or syncope, within past 5 years. Current symptoms of heart disease - dyspnea, angina, orthopnea) * Recurrent infections (more than 3 hospitalizations for invasive bacterial infections such as pneumonia or meningitis) * Current drug or alcohol abuse * Active ulcer disease or ongoing intestinal condition * Treatment for anemia in last 6 months * Currently being treated with anti-malarial drugs * Any of the following laboratory abnormalities detected during medical screening: * WBC \<0.81 x LLN or \> 1.09 x ULN * Hemoglobin \<0.91 x LLN or \>1.18 x ULN (women) or \<0.92 x LLN or \>1.18 x ULN (men) * Platelet count \<0.8 x LLN or \> 1.2 x ULN * (For leukopheresis or blood unit donations, the following lab values are exclusionary: * WBC \<3.5 or \>11 x 103/mm3; * Hemoglobin \<12.5 or \>18 g/dl * Platelet count \<150 or \>500 x 103/mm3) * SGOT or SGPT \>1.5 times normal * Positive serology for hepatitis C or HIV antibody or hepatitis B surface antigen * Positive serology for hepatitis B core antibody * Poor peripheral venous access for blood donation * Positive RPR * Other condition that in the opinion of the investigator would jeopardize the safety or rights of a volunteer participating in the trial or interfere with the scientific integrity of study. * Positive urine pregnancy test (HCG) on day of vaccination. Prior to each blood donation -females with menstrual history consistent with pregnancy. Pregnant women will not be enrolled, because immunological changes that occur during pregnancy may interfere with laboratory assays.
Where this trial is running
Baltimore, Maryland
- University of Maryland, Baltimore, Center for Vaccine Development and Global Health — Baltimore, Maryland, United States (Recruiting)
Study contacts
- Study coordinator: Susan Holian, RN
- Email: susan.holian@som.umaryland.edu
- Phone: 410-706-6156
How to participate
- Review the eligibility criteria above with your treating physician.
- Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
- Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.