A Two-stage, Phase 2b, Randomized, Double-blind, Placebo-controlled Safety, and Efficacy Study of ShigETEC, a Live, Attenuated, Oral Combination Vaccine to Prevent Shigella and ETEC Disease Delivered to Healthy Adults Ages 18 to 50 Years Old
试验速览
- 阶段
- 2 期
- 状态
- 招募中
- 入组人数
- 72
- 试验地点
- 1
- 主要终点
- Efficacy of the ShigETEC vaccine in preventing shigellosis caused by the challenge strain
研究概览
简要总结
The purpose of this study is to evaluate the efficacy of the oral, live, attenuated ShigETEC vaccine against challenge with S. flexneri 2457T.
In Stage 1 of this study, ShigETEC vaccine or placebo will be administered orally to healthy participants at a dose of 5x10^10 CFU. This dose was tested in a Phase 1 trial and found to be safe when given 4 times with an interval of 3 days between each dose.
The efficacy of ShigETEC vaccination will be evaluated in Stage 2 of this study, when participants will be challenged with S. flexneri 2457T.
The study population will be healthy adult participants in the age of 18-50 years (inclusive), which are clearly defined in the study protocol.
详细描述
This is a two-stage, randomized, double blind, placebo-controlled Phase 2b study in healthy participants conducted at a single site.
The study will be conducted in two Stages (Stage 1 and Stage 2) and two arms in Stage 1 (Arm 1 and Arm 2).
Stage 1 Stage 1 will be conducted in an outpatient setting and includes the vaccination with the investigational product, ShigETEC, a live, attenuated, oral vaccine (Arm 1) and placebo (Arm 2) and subsequent follow-up.
Stage 2 Stage 2 will include an infectious challenge of selected Stage 1 participants in an inpatient setting (CHIM: Controlled Human Infection Model) in which participants will receive 1 oral dose of Shigella flexneri 2a 2457T and be followed closely for the signs and symptoms of shigellosis.
Stage 2 will start 21 (+5) days after the last dose of vaccine or placebo.
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
- Double (Participant, Investigator)
入排标准
- 年龄范围
- 18 Years 至 50 Years（Adult）
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- 未提供
排除标准
- 未提供
研究组 & 干预措施
ShigETEC, a live, attenuated, oral vaccine
Eligible participants will be randomly assigned in a 1:1 ratio to receive either ShigETEC 5x10^10 colony forming units (CFU) or placebo. Participants will receive their assigned treatment on Days 1, 4, 7, and 10.
干预措施: ShigETEC vaccine (Biological)
Placebo
Eligible participants will be randomly assigned in a 1:1 ratio to receive either ShigETEC 5x10^10 colony forming units (CFU) or placebo. Participants will receive their assigned treatment on Days 1, 4, 7, and 10.
干预措施: Placebo (Other)
结局指标
主要结局
Efficacy of the ShigETEC vaccine in preventing shigellosis caused by the challenge strain
时间窗: Up to study day 60
The proportion of participants with incidence of shigellosis caused by the challenge strain in vaccine vs. placebo recipients until the start of antibiotic administration.
次要结局
- Safety and tolerability of ShigETEC oral vaccine(Up to 12 months after last vaccination)
- Characterization of the challenge strain shedding in stool samples(Up to study day 40)
- Severity of disease following challenge using Shigella disease score(Up to day 40)