Enterotoxigenic Escherichia Coli (ETEC) ETVAX Vaccine Trial in Bangladesh
Condition: Escherichia Coli Diarrhea
MeSH terms: Escherichia coli Infections; Diarrhea
Study type: Interventional
Phase: Phase 1/Phase 2

Summary: 
      The purpose of this study is to determine if the ETEC vaccine ETVAX with and without dmLT
      adjuvant is safe and immunogenic in adults, children, toddlers and infants in Bangladesh.
    

Detailed description: 
      This Phase I/II trial will serve to assess whether ETVAX is safe and provides mucosal as well
      as systemic immune responses against the key protective antigens when tested in different
      age-groups in Bangladesh. This study provides an opportunity to test the safety profile of a
      mucosal adjuvant, double-mutant LT (dmLT), in adults and children, as well as provide the
      opportunity to potentially assess the ability of dmLT to further enhance the mucosal and
      systemic antibody responses to key antigens in the ETVAX vaccine among age groups in
      developing country sites, like Bangladesh, that have proved refractory to oral immunization
      with enteric vaccines. In addition, this study also allows for the evaluation of the
      potential dose-sparing effect of dmLT when combined with a lower dose of vaccine. Finally,
      this clinical trial is considered an essential study along the critical path of the overall
      clinical development plan before determining whether the vaccine can be tested for protective
      efficacy in children in developing countries.
    

Intervention name(s): ETVAX; dmLT; Bicarbonate Buffer
Intervention type(s): Biological; Biological; Other
Intervention description(s): Varying dosages of liquid ETVAX vaccine (Batch BX1003574). A full dose consisted of:
Hybrid protein between the B-subunit of the E. coli heat-labile enterotoxin and the B-subunit of the cholera toxin (LCTBA): 1 mg
E. coli ETEX 21 formalin inactivated: 1.3 mg colonization factor 1 (CFA/I)
E. coli ETEX 22 formalin inactivated: 6.4 mg coli surface antigen 3 (CS3)
E. coli ETEX 23 formalin inactivated: 1.1 mg coli surface antigen 5 (CS5)
E. coli ETEX 24 phenol inactivated: 0.5 mg coli surface antigen 6 (CS6)
The vaccine was given together with sodium bicarbonate effervescent granules (Recip), which was dissolved in water and mixed with the vaccine suspension prior to oral administration. The buffer was used to prevent degradation of LCTBA hybrid protein by the gastric acid.; Varying dosages of dmLT, a derivative of wild-type enterotoxigenic Escherichia coli LT that has been genetically modified by replacing the arginine at amino acid position 192 with glycine and the leucine at amino acid position 211 with alanine. These two amino acid substitutions take place in proteolytic cleavage sites which are critical for activation of the secreted toxin molecules.; Sodium bicarbonate buffer dissolved in 150 ml of potable water
Other intervention name(s): double mutant heat labile toxin, LT(R192G/L211A)
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
Primary purpose: Prevention
Keywords: ETEC diarrhea; Escherichia Coli (ETEC)