A Cluster-randomised Controlled Phase IV Trial Assessing the Impact of a Vi-Polysaccharide Conjugate Vaccine in Preventing Typhoid Infection in Asante Akim, Ghana (TyVEGHA)
试验速览
- 阶段
- 4 期
- 状态
- 招募中
- 入组人数
- 23,000
- 试验地点
- 2
- 主要终点
- Total Protection
研究概览
简要总结
A cluster-randomised controlled Phase IV trial (cRCT) assessing the impact of a Vi-Polysaccharide conjugate vaccine in preventing typhoid infection in Asante Akim, Ghana (TyVEGHA) with a primary endpoint of determining the total protection conferred by single-dose vaccination with Vi-TT against blood culture-confirmed symptomatic S. Typhi infection in the intervention vaccine clusters, compared with the control vaccine clusters.
详细描述
Typhoid fever remains a significant health problem in sub-Saharan Africa, with incidence rates >100 cases per 100,000 person-years of observation. Despite the prequalification of safe and effective typhoid conjugate vaccines (TCV), the uptake of these vaccines in African countries has remained low. Real-life effectiveness data, which inform public health programs on the impact of TCVs in reducing typhoid-related mortality and morbidity, are critical to enhancing the introduction of TCVs in high-burden settings. Here we describe a cluster-randomized trial to investigate population-level protection of TCV against blood culture-confirmed typhoid fever. A total of 80 geographically distinct clusters have been delineated within the Agogo district of the Asante Akim region in Ghana. Clusters will be randomized to the intervention arm receiving TCV or a control arm receiving the meningococcal A conjugate vaccine. The primary study endpoint is the overall protection of TCV against blood culture-confirmed typhoid fever. Total, direct, and indirect protection will be measured as secondary outcomes. Blood culture-based enhanced surveillance will enable the estimation of incidence rates in the intervention and control clusters. Evaluation of the real-world impact of TCVs will improve uptake of prequalified/licensed safe and effective typhoid vaccines in public health programs of high burden settings.
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Parallel
- 主要目的
- Prevention
- 盲法
- Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
入排标准
- 年龄范围
- 9 Months 至 15 Years（Child）
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- •In order to be eligible to participate in this study, an individual must meet the following criteria:
- •Healthy participants aged 9 months to <16 years (i.e., ≤15 years and 364 days) of age at the time of vaccination
- •Participants/Parents/legally authorized representative (LAR) who have voluntarily given informed assent (sought from participants aged 12 years to <16 years) and informed consent
- •Participants/Parents/LAR living within study target area at the time of vaccination and willing to follow the study procedures and be available for the entire duration of the study
排除标准
- •An individual who meets any of the following criteria will be excluded from participation in this study:
- •Known allergy to any vaccine component
- •Self-reported ongoing acute and/or chronic illness
- •Any self-reported coagulopathies
- •Any medical or social compelling reasons in the judgment of a clinical physician
- •Self-reported pregnancy/Positive urine pregnancy test or lactating
- •Previous typhoid vaccination in the last 5 years (proven by the presentation of a vaccine card or self-reporting).
- •Temporary exclusion criteria
- •Self-reported fever (elevated tympanic (≥38°C) or axillary temperature (≥37.5°C)) within 24 hours of vaccination
- •Self-reported use of antipyretics within 4hours prior to vaccination
- •Any other vaccination during the last 4 weeks (proven by the presentation of a vaccine card or self-reporting)
- •Girls ≥11 years of age with self-reported irregular menstruation or who do not know their last menstruation date
研究组 & 干预措施
MCV-A arm
A single dose of MCV-A vaccine to the comparator group.
干预措施: MCV-A vaccine (Biological)
结局指标
主要结局
Total Protection
时间窗: 3 years
The incidence of blood culture-confirmed symptomatic TF in all vaccine recipients of the intervention clusters, compared with control clusters.
次要结局
- Seroconversion rates(3 years)
- Overall protection against clinical typhoid.(3 years)
- Overall protection(3 years)
- Total protection against severe typhoid.(3 years)
- Total protection against clinical typhoid.(3 years)
- Indirect Protection aganist Blood Culture Confirmed Typhoid.(3 years)
- Geometric mean titers(3 years)
- Safety Assessment(3 years)