Collection of Blood Samples for In-Vitro Studies from Healthy Adult Blood Donors Who Have Received Oral Typhoid Vaccine (TY21A)
试验速览
- 阶段
- 4 期
- 状态
- 招募中
- 入组人数
- 150
- 试验地点
- 1
- 主要终点
- Percentage of Responders
研究概览
简要总结
This is an open-label, non-randomized study. Volunteers will be vaccinated with the typhoid oral vaccine, Vivotif. Vivotif has been licensed by the Food and Drug Administration (FDA) for travelers to developing countries. Volunteers will also be asked to provide blood, saliva, and stool specimens over a follow-up time period of up to eight years. The specimens obtained in this clinical research study will be used to further the investigator's understanding of the protective immunological mechanisms that can be elicited systemically and may be applicable to other enteric pathogens.
研究设计
- 研究类型
- Interventional
- 分配方式
- Na
- 干预模型
- Single Group
- 主要目的
- Basic Science
- 盲法
- None
入排标准
- 年龄范围
- 18 Years 至 —（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- •Age 18 years and older
- •Good general health as determined by a screening evaluation within 28 days before blood donation
- •Informed, written consent
排除标准
- •History of any of the following medical illnesses:
- •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.
研究组 & 干预措施
Vaccination with Oral Typhoid Vaccine (Vivotif)
Volunteers receive immunization with Vivotif oral typhoid vaccine. Blood, saliva, and stool specimens are collected at subsequent visits.
干预措施: Vivotif Typhoid Oral Vaccine (Drug)
结局指标
主要结局
Percentage of Responders
时间窗: 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.
次要结局
未报告次要终点
研究者
Wilbur Chen, MD, MS
Professor
University of Maryland, Baltimore