Efficacy and Safety of an H.Pylori Vaccine in H.Pylori-Negative Adults

Study Overview
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Brief Summary
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To study the safety, immunogenicity and efficacy of an investigational H. pylori vaccine, compared with placebo.

Official Title
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Phase I/II, Randomized, Observer-blind, Placebo-controlled, Single-Center Study of the Tolerability, Immunogenicity, and Efficacy of an Novartis' Investigational H. Pylori Vaccine in H. Pylori-Negative Adults

Conditions
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Helicobacter Pylori Infection

Intervention / Treatment
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* Biological: H.pylori vaccines
* Biological: Placebo Vaccine


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: adults 18 - 40 years of age in good health HP uninfected not pregnant and agree to use birth control throughout the study (females who can become pregnant) Exclusion Criteria: remote or current HP infection

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 40 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Prevention
Allocation: Randomized
Intervention Model: Single Group Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: 1<br> | Biological: H.pylori vaccines<br>* 1 dose of H.pylori vaccine at 0, 1, and 2 months<br>|
| Placebo Comparator: 2<br> | Biological: Placebo Vaccine<br>* Placebo Vaccine at 0, 1, and 2 months<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The Efficacy (Defined as Prevention of Infection) of the HP Vaccine Compared to Placebo. | The efficacy of the investigational vaccine to prevent infection following H.pylori challenge in healthy adults was determined in terms of percentage of subjects with positive HP infections in the vaccinated and unvaccinated groups(Placebo). Infection rates was assessed by invasive Upper Gastrointestinal Endoscopy (UGE)tests that included HP histopathology, HP culture and rapid urease test (RUT), and non-invasive HP tests which included urea breath test (UBT) and fecal antigen test (FAT). | 12 weeks post HP challenge | 
| Number of Subjects Reporting Solicited Local* and Systemic Adverse Events Following Vaccination | To assess the tolerability of an HP vaccine versus placebo in terms of number of subjects reporting solicited local* and systemic adverse events. | Day 1-7 post vaccination | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The Time Course of HP Infection Following HP Challenge in Vaccinated and Placebo Groups | The time course of HP infection following HP challenge in subjects of the HP vaccine and placebo groups, were assessed by non-invasive HP tests. | 12 months | 
| The Geometric Mean Concentrations After HP Vaccination. | The geometric mean concentration of IgG antibody responses to each of the HP vaccine antigens (VacA, CagA and NAP)after HP vaccination as compared to placebo are reported. | upto 1 month after 3rd vaccination | 
| Geometric Mean Concentrations Against Vaccine Antigens After HP Challenge. | The geometric mean concentration of IgG antibody responses to each of the HP vaccine antigens (VacA, CagA and NAP) after HP challenge were compared between vaccinated and placebo groups. | 12 months | 
| Response on Activated Regulatory T Cell Subset Following HP Vaccination and HP Challenge | The response to 3 doses of HP vaccine and the oral HP challenge was assessed with respect their ability to induce differentiation and changes in the phenotype of a subset of regulatory T-cells CD4+CD25+Foxp3+ that expresses Treg Markers PD-1 and/or HLA-DR. | 12 weeks post HP challenge | 
| Proliferative Response Against the Pooled H. Pylori Vaccine Antigens by Stimulation Index (SI) | The proliferation of H. pylori-specific Peripheral blood mononuclear cells (PBMCs) following HP antigen stimulation was assessed to measure the magnitude of the cell mediated immune response. | 12 weeks post HP challenge | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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helicobacter pylori infection, vaccination, adults