Cross-reactive Immunity Elicited by Oral and Parenteral Typhoid Vaccines Against Non-typhoid Salmonellae
试验速览
- 阶段
- 4 期
- 入组人数
- 100
- 试验地点
- 6
- 主要终点
- Number of circulating plasmablasts specific to various Salmonella strains
研究概览
简要总结
In a recent controlled study, the investigators explored cross-reactive immune responses against different Salmonella spp. in healthy volunteers immunized with either the oral (Vivotif® ) or parenteral (Typherix®) typhoid vaccines (ISRCTN68125331). In the present study immune responses will be studied in a group receiving both of these vaccines and in the previously immunized volunteers after booster immunization (same groups receive same vaccines 2-4 years after primary immunization).
详细描述
Many Salmonella spp causing gastroenteritis share O antigen serotypes with Salmonella enteritidis subsp. enterica serovar Typhi (S.typhi) and could therefore be in 'reach' of the protective efficacy of the oral live typhoid fever vaccine Vivotif®. Some of these Salmonellae are common causes of diarrhoea in travellers (0-30% of travellers diarrhea depending on the area). In a recent controlled study, the investigators showed that a cross-reactive immune response is elicited against different Salmonella spp. in healthy volunteers immunized with either the oral (Vivotif® ) or parenteral (Typherix®) typhoid vaccines (ISRCTN68125331).
In the present study immune responses will be studied in a group receiving both of these vaccines and in previously immunized volunteers after booster immunization (same groups receive same vaccines 2-4 years after primary immunization; groups: Vivotif / Typherix / Vivotif + Typherix). The results are compared to those obtained after primary immunization.
研究设计
- 研究类型
- Interventional
- 分配方式
- Non Randomized
- 干预模型
- Parallel
- 主要目的
- Prevention
- 盲法
- None
入排标准
- 年龄范围
- 18 Years 至 64 Years（Adult）
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- •Male or female subjects aged ≥18 to ≤65 years
- •General good health as established by medical history and physical examination
- •Written informed consent
- •Females of childbearing potential must agree to use an efficacious hormonal or barrier method of birth control during the study. Abstinence is acceptable.
- •Available for all visits scheduled in this study.
排除标准
- •Primary groups: Vaccination against typhoid fever within 5 years before dosing.
- •History of clinical typhoid fever, clinical paratyphoid A or B fever.
- •Immunization with any other vaccine (oral or parenteral) within 4 weeks prior to study start or planned vaccination during the study
- •Current intake of antibiotics or end of antibiotic therapy <8 days before first IMP administration
- •Chronic (longer than 14 days) administration of immunosuppressants or other immune-modifying drugs within 6 months before the first dose of investigational vaccine; oral corticosteroids in dosages of ≥0.5 mg/kg/d prednisolone or equivalent are excluded; inhaled or topical steroids are allowed
- •Acute or chronic clinically significant gastrointestinal disease
结局指标
主要结局
Number of circulating plasmablasts specific to various Salmonella strains
时间窗: 7 days
To study whether cross-reactive immune response is similar * if the two vaccines are given simultaneously * after booster immunization than after primary immunization
次要结局
- Level of serum antibodies specific to various Salmonella strains(28 days)
研究者
Anu Kantele
Associate professor
Helsinki University Central Hospital