Clinical Trials Logo

Clinical Trial Summary

Using an established model of human typhoid infection, whereby healthy adults are deliberately exposed to typhoid-causing bacteria, the investigators will determine how effective a new typhoid conjugate vaccine (Vi-TCV) is in preventing infection. The new typhoid vaccine will be compared with a control vaccine (meningococcal ACWY). The protective effect of a currently used typhoid polysaccharide vaccine (Vi-PS) will also be studied and compared with the control vaccine using this model of typhoid infection. A second component of this study will involve vaccinating 15-20 participants with Vi-PS. Serum will be obtained prior to vaccination and 4-6 weeks after vaccination. The post-vaccination serum will be pooled and used to create an anti-Vi IgG serum standard.


Clinical Trial Description

Typhoid fever is an infection caused by a bacterium, Salmonella Typhi, that only causes disease in humans. It is transmitted faecal-orally and causes more than 22 million infections every year in developing countries, such as areas of Asia, Africa and South America, where access to clean drinking water and sanitation facilities is limited. Although typhoid fever is treatable with effective antibiotics, there are more than 200,000 deaths every year in these resource-limited regions. Salmonella Typhi could be eradicated but improving sanitation and living conditions in endemic regions is difficult. Vaccination to prevent the transmission of Salmonella Typhi could significantly reduce the burden of disease. The currently licensed typhoid vaccines are only moderately effective in preventing infection in people who have been immunised and no vaccines are licensed for use in young children. Novel typhoid vaccines have been developed to overcome these problems, but more research and information is needed to study how well these vaccines work before they can be routinely used. This study proposes to investigate the protective effect of a novel typhoid vaccine (typhoid Vi polysaccharide capsule - tetanus toxoid conjugate vaccine) using a human challenge model of typhoid infection. Healthy adults will be vaccinated with the novel typhoid vaccine, a currently used typhoid vaccine (Vi polysaccharide capsule vaccine) or a control vaccine. One month after vaccination, participants will be exposed to live Salmonella Typhi by drinking a solution containing the bacteria. Participants will then be closely monitored to determine which participants develop infection and which are protected. In addition to assessing the protective effect of conjugated and unconjugated typhoid vaccines, the effect the vaccines have on the immune system and on the clinical course of typhoid infection will also be studied. It is hoped that the knowledge gained from this study will contribute to the use of vaccines against Salmonella Typhi to help control this preventable disease. ;


Study Design


Related Conditions & MeSH terms


NCT number NCT02324751
Study type Interventional
Source University of Oxford
Contact
Status Completed
Phase Phase 2
Start date September 2015
Completion date June 27, 2022

See also
  Status Clinical Trial Phase
Completed NCT04830371 - Non-inferiority and Safety Study of EuTCV Compared to Typbar-TCV in Healthy 6 Months-45 Years Aged Participants Phase 2/Phase 3
Recruiting NCT04543877 - WHNRC (Western Human Nutrition Research Center) Fiber Intervention Study Early Phase 1
Completed NCT01421693 - Gatifloxacin Versus Ceftriaxone in the Treatment of Enteric Fever Phase 4
Completed NCT05579821 - Evaluation Study of DPP® Typhoid Assay
Completed NCT02947295 - Global Genomic and Proteomic Profiling of African Children With Typhoid Fever
Completed NCT01405521 - Understanding Typhoid Disease After Vaccination Phase 2
Completed NCT00386789 - Long Term Protection by and Persistence of Vi Antibodies Induced by Vi-rEPA Conjugate Vaccines in Vietnamese Children Injected at 2-5 Years or at 5-8 Years of Age N/A
Completed NCT04801602 - Commercial Typhoid Tests Validation Trial
Recruiting NCT06104345 - Immune Response Elicited by Concomitant Administration of Oral Typhoid Fever (Vivotif®) and Cholera (Dukoral®) Vaccines Phase 4
Completed NCT01438996 - Extension Study of H01_04TP to Evaluate the Booster Response Induced by Vi-CRM197 in Adults Phase 2
Completed NCT01437267 - Safety and Immunogenicity of Vi-CRM197 Vaccine Against S. Typhi in Children, Older Infants and Infants Phase 2
Completed NCT01193907 - Safety and Immunogenicity of Three Formulations of Vi-CRM197 Vaccine Against S. Typhi in Adults (18-40 Years Old) Phase 2
Recruiting NCT04349826 - The Azithromycin and Cefixime Treatment of Typhoid in South Asia Trial (ACT-South Asia Trial) Phase 4
Completed NCT01608815 - Study of a Single Dose of SP093 Typhoid Vi Polysaccharide Vaccine in Japanese Subjects Phase 3
Completed NCT01123941 - Safety and Immunogenicity of Vi-CRM197 Vaccine Against S. Typhi in Adult (18-40 Years Old) Phase 1
Recruiting NCT05500482 - Vellore Typhoid Vaccine Impact Trial Phase 4
Completed NCT03926455 - Safety and Immunogenicity of Typhax, a Typhoid Vaccine Phase 1
Completed NCT01229176 - Safety and Immunogenicity of Vi-CRM197 Vaccine Against S. Typhi in Adults, Children, Older Infants and Infants Phase 2
Completed NCT03956524 - Safety and Tolerability of Typhoid Conjugate Vaccine (EuTCV) in Healthy Adults Phase 1
Completed NCT04154722 - Comparison of Two Drugs Regimen in Treatment of Complicated Typhoid Fever in Children Phase 4