Clinical Research Directory

CVD 37000: Immunity and Microbiome Studies at Intestinal and Systemic Sites in Ty21a Vaccinated Adults

This is an open-label, non-randomized study. The purpose of this study is to better understand how vaccines against typhoid fever affect the normal immune system and bacteria in the intestine. Patients having standard-of-care colonoscopies will be divided into 3 groups: Group 1: Vivotif typhoid vaccination then colonoscopy; Group 2: Colonoscopy, then Vivotif typhoid vaccination, then follow-up colonoscopy; Group 3: Colonoscopy without vaccination. The Vivotif typhoid vaccine used in this study is licensed by the Food and Drug Administration (FDA) for travelers to developing countries. Volunteers will be asked to donate tissue, blood, saliva and stool samples for studying how the body responds to the typhoid vaccine.

ZyVac-TCV Bangladesh Study

This is a prospective closed cohort, open-label, phase III effectiveness study using a test-negative design of a typhoid conjugate vaccine, ZyVac® TCV (purified Vi capsular polysaccharide of Salmonella Typhi conjugated to tetanus toxoid as carrier protein), manufactured by Zydus Lifesciences Limited. The study will be conducted in a closed cohort population among children aged 6 months to 15 years residing in wards 5, 6, 7, 48, 49, 50, 63, 71, and 72 of Dhaka South City Corporation (DSCC). The targeted number of age-eligible children in the study area is \~92,000 among them \~60,000 will be vaccinated. A subset of the first 600 consenting participants will be selected by age strata (6 months to \<2 years, 2-4 years, 5-15 years) for enrollment in the immunogenicity study with an additional three follow-up visits. Diary cards will be used to collect adverse events (AEs) following immunization (AEFI) data up to day 7 for a subset of active follow-up of the first 600 vaccinated participants. Participants not in this subset will be encouraged to go to the 'Adverse Event Monitoring Cell' at the Maniknagar field office. Data on serious adverse events (SAEs) will be reported for six months after vaccination. All study updates including AEs and SAEs will be reported to the data safety and monitoring board (DSMB) and sponsor. Passive surveillance for typhoid fever will be carried out in the Maniknagar field office and Mugda Medical College and Hospital in the catchment area among the age-eligible children.