Study Confirming A Human Challenge Model and Investigating The Safety Of VLA1701
Condition: Enterotoxigenic Escherichia Coli Infection; Diarrhea
MeSH terms: Escherichia coli Infections; Diarrhea
Intervention: VLA1701; Placebo; Challenge Strain
Intervention description: VLA1701 is an investigational oral vaccine against LT-ETEC (Labile Toxin-Enterotoxigenic E coli); buffer component of VLA1701; LSN03-016011/A
Phase: Phase 2
Study type: Interventional
Primary purpose: Prevention
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Double (Participant, Investigator)
Masking description: Double (Participant, Investigator)
Enrollment: 34.0
Sex: All
Minimum age: 18 Years
Maximum age: 49 Years
Healthy volunteers: Accepts Healthy Volunteers

Summary:

      This is a single-center, double-blind, placebo-controlled, Phase II vaccination and challenge
      study designed to confirm a human challenge model with E. coli strain LSN03-016011/A.
    

Eligibility criteria:

        Inclusion Criteria:

          1. Healthy male and non-pregnant female subjects aged 18 to <50 years;

          2. BMI of 19.0 to 35.0 kg/m2

          3. Willingness to participate after informed consent has been obtained from the subject
             prior to any study related procedures.

          4. Completion of a training session and demonstration of comprehension of the protocol
             procedures and knowledge of ETEC-associated illness by passing a written examination.

          5. If subject is of childbearing potential:

               1. Negative pregnancy test at screening with understanding to not become pregnant
                  within 28 days after challenge;

               2. Subject has practiced an effective method of contraception during the 30 days
                  before screening (Visit 0);

               3. Subject agrees to employ adequate birth control measures for the duration of the
                  study.

        Exclusion Criteria

          1. Participated in research involving investigational product within 30 days before
             planned date of first vaccination or planned use through Day 44;

          2. Any prior exposure to ETEC (including LSN03-016011/A) or cholera occupationally or
             received LT (Or any mutant forms of LT (e.g., LTR192G, LTR192GL211A), ETEC, or cholera
             vaccine);

          3. Subjects with known abnormal stooling patterns (fewer than 3 per week or more than 3
             per day);

          4. Known allergies to any component of the vaccine;

          5. Subjects with known allergies to more than 1 planned antibiotics:

          6. History of diarrhea while traveling in a developing country within the last 3 years;

          7. Subjects whose occupation involves handling of ETEC or cholera bacteria;

          8. Women who are pregnant or breastfeeding;

          9. Significant medical conditions including chronic, immunosuppressive, malignant, or
             gastrointestinal diseases (e.g. History of Irritable Bowel Syndrome (as defined by the
             Rome III criteria or medical diagnosis) or gastric ulcer disease) or enteric,
             pulmonary, cardiac, liver or renal disease. Some medical conditions which are
             adequately treated and stable may be acceptable in the study (e.g. hypertension);

         10. Significant abnormalities in screening lab hematology or serum chemistries;

         11. Use of any medication known to effect the immune system (e.g. systemic
             corticosteroids) within 30 days of vaccination or planned use during active study
             period (excluding inhaled steroids);

         12. Evidence of confirmed infection with HIV, Hepatitis B or Hepatitis C;

         13. Subjects with IgA (Immunoglobulin A) deficiency (serum IgA < 7 mg/dl or limit of
             detection of assay);

         14. Regular use of antacids, antidiarrheal, loperamide, bismuth subsalicylate,
             diphenoxylate or similar medication less than 2 weeks prior to enrolling in the study
             and through the inpatient portion of the study;

         15. Known or suspected alcohol abuse or illicit drug use within the last year, positive
             urine toxicology for drugs of abuse;

         16. Persons who are committed to an institution (by virtue of an order issued either by
             the judicial or the administrative authorities);

         17. Persons who are in a dependent relationship with the sponsor, an investigator or other
             study team members, or the study center.

         18. Any other criteria which, in the investigator's opinion, would compromise the ability
             of the subject to participate in the study, the safety of the study, or the results of
             the study.