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Dose Escalating Study of a Prototype CS6 Subunit Vaccine With a Modified Heat-labile Enterotoxin From Enterotoxigenic Escherichia Coli (ETEC)

Primary Purpose

Diarrhea

Status
Completed
Phase
Phase 1
Locations
United States
Study Type
Interventional
Intervention
CssBA
dmLT
Sponsored by
PATH
About
Eligibility
Locations
Arms
Outcomes
Full info

About this trial

This is an interventional prevention trial for Diarrhea focused on measuring ETEC, Escherichia coli, enteric

Eligibility Criteria

18 Years - 45 Years (Adult)All SexesAccepts Healthy Volunteers

Inclusion Criteria:

  1. Healthy, adult, male or female, age 18 to 45 years (inclusive) at the time of enrollment.
  2. Completion and review of comprehension test (achieved > 70% accuracy).
  3. Signed informed consent document.
  4. Available for the required follow-up period and scheduled clinic visits.
  5. Women: Negative pregnancy test with understanding (through informed consent process) to not become pregnant during the study or within three (3) months following last vaccination.

Exclusion Criteria:

  1. Health problems (for example, intercurrent febrile illness, chronic medical conditions such as psychiatric conditions, diabetes mellitus, hypertension or any other condition that might place the subject at increased risk of adverse events) - study clinicians, in consultation with the PI, will use clinical judgment on a case-by-case basis to assess safety risks under this criterion. The PI will consult with the Research Monitor as appropriate.
  2. Clinically significant abnormalities on physical examination.
  3. Immunosuppressive drugs (use of systemic corticosteroids or chemotherapeutics that may influence antibody development) or illness (including immunoglobulin A [IgA] deficiency, defined by serum IgA < 7 mg/dL).
  4. Women who are pregnant or planning to become pregnant during the study period plus three (3) months beyond the last received dose and currently nursing women.
  5. Participation in research involving another investigational product (defined as receipt of investigational product or exposure to invasive investigational device) 30 days before planned date of first vaccination or anytime through the last study safety visit.
  6. Positive blood test for Hepatitis B surface antigen (HBsAg), Hepatitis C virus (HCV), human immunodeficiency virus (HIV)-1/2.
  7. Clinically significant abnormalities on basic laboratory screening.
  8. Exclusionary skin disease history/findings that would confound assessment or prevent appropriate local monitoring of adverse events (AEs), or possibly increase the risk of a local AE
  9. History of chronic skin disease (clinician judgement)
  10. Acute skin infection/eruptions on the upper arms including fungal infections, severe acne or active contact dermatitis
  11. Allergies that may increase the risk of AEs
  12. Regular use (weekly or more often) of antidiarrheal, anti-constipation, or antacid therapy
  13. Abnormal stool pattern (fewer than 3 stools per week or more than 3 stools per day) on a regular basis; loose or liquid stools on other than an occasional basis
  14. History of microbiologically confirmed ETEC or cholera infection in the last 3 years
  15. Travel to countries where ETEC or V. cholerae or other enteric infections are endemic (most of the developing world) within 3 years prior to dosing (clinician judgement)
  16. Symptoms consistent with Travelers' Diarrhea or concurrent with travel to countries where ETEC infection is endemic (most of the developing world) within 3 years prior to dosing, OR planned travel to endemic countries during the length of the study
  17. Vaccination for or ingestion of ETEC, cholera, or E. coli heat labile toxin within 3 years prior to dosing
  18. Occupation involving handling of ETEC or V. cholerae currently, or in the past 3 years

Sites / Locations

  • Walter Reed Army Institute of Research Clinical Trial Center

Arms of the Study

Arm 1

Arm 2

Arm 3

Arm 4

Arm 5

Arm 6

Arm Type

Experimental

Experimental

Experimental

Experimental

Experimental

Experimental

Arm Label

Group A1: CssBA 5 ug

Group A2: DmLT 100 ng

Group B: CssBA 5 ug + DmLT 100 ng

Group C: CssBA 5 ug + DmLT 500 ng

Group D: CssBA 15 ug + DmLT 500 ng

Group E: CssBA 45 ug + DmLT 500 ng

Arm Description

Participants received an intramuscular injection of 5 ug CssBA on days 1, 22, and 43.

Participants received an intramuscular injection of 100 ng DmLT on days 1, 22, and 43.

Participants received an intramuscular injection of 5 ug CssBA + 100 ng dmLT on days 1, 22, and 43.

Participants received an intramuscular injection of 5 ug CssBA + 500 ng dmLT on days 1, 22, and 43.

Participants received an intramuscular injection of 15 ug CssBA + 500 ng dmLT on days 1, 22, and 43.

Participants received an intramuscular injection of 45 ug CssBA + 500 ng dmLT on days 1, 22, and 43.

Outcomes

Primary Outcome Measures

Number of Participants With Solicited Adverse Events
Solicited adverse events included vaccine site pain, vaccine site pruritus, vaccine site rash/eruption, vaccine site swelling, vaccine site tenderness, fever, headache, diarrhea, arthralgia, myalgia, malaise, nausea, and vomiting. Adverse events were assessed for severity by the investigator according to the following: Mild (Grade 1): Does not interfere with routine activities, minimal level of discomfort Moderate (Grade 2): Interferes with routine activities, moderate level of discomfort Severe (Grade 3): Unable to perform routine activities, significant level of discomfort Potentially life-threatening (Grade 4): Hospitalization or emergency room (ER) visit for potentially life-threatening event
Number of Participants With Unsolicited Adverse Events
Adverse events were assessed for severity by the investigator according to the following: Mild (Grade 1): Does not interfere with routine activities Minimal level of discomfort Moderate (Grade 2): Interferes with routine activities Moderate level of discomfort Severe (Grade 3): Unable to perform routine activities Significant level of discomfort Potentially life-threatening (Grade 4): Hospitalization or emergency room (ER) visit for potentially life-threatening event

Secondary Outcome Measures

Percentage of Participants With a Serum Immunologic Response to Coli Surface Antigen 6 (CS6)
Serum samples were assayed for immunoglobulin G (IgG) and immunoglobulin A (IgA) antibody titers against CS6 using an enzyme-linked Immunosorbent assay (ELISA). Immunologic response was defined as a ≥ 4-fold increase in reciprocal endpoint titer between Baseline and any post-vaccination sample.
Percentage of Participants With a Serum Immunologic Response to Labile Toxin
Serum samples were assayed for immunoglobulin G (IgG) and immunoglobulin A (IgA) antibody titers against labile toxin using an enzyme-linked Immunosorbent assay (ELISA). Immunologic response was defined as a ≥ 4-fold increase in reciprocal endpoint titer between Baseline and any post-vaccination sample.
Percentage of Participants With a Mucosal Immunologic Response to Coli Surface Antigen 6 (CS6)
Peripheral blood mononuclear cells (PBMCs) were collected to determine antibody responses from lymphocyte supernatant against CS6 at Baseline and 7 days after each vaccination. Antibody in lymphocyte supernatant (ALS) is an indirect quantification of antibody secreting cells (ASC) activated in the mucosa that circulate in the peripheral blood about seven days post-mucosal immunization/infection. After incubation, lymphocyte supernatant was assayed for antigen-specific IgG and IgA antibodies using ELISA. A positive ALS response was defined as a four-fold rise in antibody titers between Baseline and any post vaccination sample.
Percentage of Participants With a Mucosal Immunologic Response to Labile Toxin
Peripheral blood mononuclear cells (PBMCs) were collected to determine antibody responses from lymphocyte supernatant against labile toxin at Baseline and 7 days after each vaccination. Antibody in lymphocyte supernatant (ALS) is an indirect quantification of antibody secreting cells (ASC) activated in the mucosa that circulate in the peripheral blood about seven days post-mucosal immunization/infection. After incubation, lymphocyte supernatant was assayed for antigen-specific IgG and IgA antibodies using ELISA. A positive ALS response was defined as a four-fold rise in antibody titers between Baseline and any post vaccination sample.
Geometric Mean Titer of Serum Anti-CS6 Immunoglobulin G Antibodies
Serum samples were assayed for IgG antibody titers against CS6 using an enzyme-linked Immunosorbent assay (ELISA).
Geometric Mean Titer of Serum Anti-CS6 Immunoglobulin A Antibodies
Serum samples were assayed for IgA antibody titers against CS6 using an enzyme-linked Immunosorbent assay (ELISA).
Geometric Mean Titer of Serum Anti-LT Immunoglobulin G Antibodies
Serum samples were assayed for IgG antibody titers against labile toxin using an enzyme-linked Immunosorbent assay (ELISA).
Geometric Mean Titer of Serum Anti-LT Immunoglobulin A Antibodies
Serum samples were assayed for IgA antibody titers against labile toxin using an enzyme-linked Immunosorbent assay (ELISA).
Geometric Mean Titer of Antibody Lymphocyte Supernatant Anti-CS6 Immunoglobulin G Antibodies
Lymphocyte supernatant was assayed for IgG antibody titers against CS6 using ELISA.
Geometric Mean Titer of Antibody Lymphocyte Supernatant Anti-CS6 Immunoglobulin A Antibodies
Lymphocyte supernatant was assayed for IgA antibody titers against CS6 using ELISA.
Geometric Mean Titer of Antibody Lymphocyte Supernatant Anti-LT Immunoglobulin G Antibodies
Lymphocyte supernatant was assayed for IgG antibody titers against labile toxin using ELISA.
Geometric Mean Titer of Antibody Lymphocyte Supernatant Anti-LT Immunoglobulin A Antibodies
Lymphocyte supernatant was assayed for IgA antibody titers against labile toxin using ELISA.

Full Information

First Posted
January 10, 2018
Last Updated
December 10, 2020
Sponsor
PATH
Collaborators
Naval Medical Research Center, Walter Reed Army Institute of Research Clinical Trials Center
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1. Study Identification

Unique Protocol Identification Number
NCT03404674
Brief Title
Dose Escalating Study of a Prototype CS6 Subunit Vaccine With a Modified Heat-labile Enterotoxin From Enterotoxigenic Escherichia Coli (ETEC)
Official Title
A Phase 1 Dose Escalating Study of a Prototype CS6 Subunit Vaccine With a Modified Heat-labile Enterotoxin From Enterotoxigenic Escherichia Coli (ETEC)
Study Type
Interventional

2. Study Status

Record Verification Date
November 2020
Overall Recruitment Status
Completed
Study Start Date
January 16, 2018 (Actual)
Primary Completion Date
March 26, 2019 (Actual)
Study Completion Date
March 26, 2019 (Actual)

3. Sponsor/Collaborators

Responsible Party, by Official Title
Sponsor
Name of the Sponsor
PATH
Collaborators
Naval Medical Research Center, Walter Reed Army Institute of Research Clinical Trials Center

4. Oversight

Studies a U.S. FDA-regulated Drug Product
Yes
Studies a U.S. FDA-regulated Device Product
No
Data Monitoring Committee
Yes

5. Study Description

Brief Summary
This study will evaluate the safety of a prototype Coli surface antigen 6 (CS6) subunit vaccine (CssBA) alone or in combination with Escherichia coli double mutant heat labile toxin (dmLT) given by intramuscular (IM) injection.
Detailed Description
This is an open-label clinical trial in which a total of 50 participants will receive three injections of either CssBA alone, dmLT alone or CssBA + dmLT. The vaccine will be administered via IM injection to alternating deltoid regions on days 1, 22, and 43. Each participant will receive the same dose at each vaccination dependent upon group assignment. Group A is considered a pilot group in which all 3 doses will be administered and participants monitored for safety 7 days after the third vaccination, prior to the enrollment of participants in Group B.

6. Conditions and Keywords

Primary Disease or Condition Being Studied in the Trial, or the Focus of the Study
Diarrhea
Keywords
ETEC, Escherichia coli, enteric

7. Study Design

Primary Purpose
Prevention
Study Phase
Phase 1
Interventional Study Model
Sequential Assignment
Masking
None (Open Label)
Allocation
Non-Randomized
Enrollment
50 (Actual)

8. Arms, Groups, and Interventions

Arm Title
Group A1: CssBA 5 ug
Arm Type
Experimental
Arm Description
Participants received an intramuscular injection of 5 ug CssBA on days 1, 22, and 43.
Arm Title
Group A2: DmLT 100 ng
Arm Type
Experimental
Arm Description
Participants received an intramuscular injection of 100 ng DmLT on days 1, 22, and 43.
Arm Title
Group B: CssBA 5 ug + DmLT 100 ng
Arm Type
Experimental
Arm Description
Participants received an intramuscular injection of 5 ug CssBA + 100 ng dmLT on days 1, 22, and 43.
Arm Title
Group C: CssBA 5 ug + DmLT 500 ng
Arm Type
Experimental
Arm Description
Participants received an intramuscular injection of 5 ug CssBA + 500 ng dmLT on days 1, 22, and 43.
Arm Title
Group D: CssBA 15 ug + DmLT 500 ng
Arm Type
Experimental
Arm Description
Participants received an intramuscular injection of 15 ug CssBA + 500 ng dmLT on days 1, 22, and 43.
Arm Title
Group E: CssBA 45 ug + DmLT 500 ng
Arm Type
Experimental
Arm Description
Participants received an intramuscular injection of 45 ug CssBA + 500 ng dmLT on days 1, 22, and 43.
Intervention Type
Biological
Intervention Name(s)
CssBA
Other Intervention Name(s)
spd_dsc16Bntd14CssBAB7A[His]₆
Intervention Description
Recombinant enterotoxigenic Escherichia coli (ETEC) surface antigen 6 containing modified structural subunits A and B
Intervention Type
Biological
Intervention Name(s)
dmLT
Intervention Description
Escherichia coli double mutant heat-labile toxin with mutations at amino acids 192 and 211
Primary Outcome Measure Information:
Title
Number of Participants With Solicited Adverse Events
Description
Solicited adverse events included vaccine site pain, vaccine site pruritus, vaccine site rash/eruption, vaccine site swelling, vaccine site tenderness, fever, headache, diarrhea, arthralgia, myalgia, malaise, nausea, and vomiting. Adverse events were assessed for severity by the investigator according to the following: Mild (Grade 1): Does not interfere with routine activities, minimal level of discomfort Moderate (Grade 2): Interferes with routine activities, moderate level of discomfort Severe (Grade 3): Unable to perform routine activities, significant level of discomfort Potentially life-threatening (Grade 4): Hospitalization or emergency room (ER) visit for potentially life-threatening event
Time Frame
From first vaccination to 28 days after the third vaccination, 71 days.
Title
Number of Participants With Unsolicited Adverse Events
Description
Adverse events were assessed for severity by the investigator according to the following: Mild (Grade 1): Does not interfere with routine activities Minimal level of discomfort Moderate (Grade 2): Interferes with routine activities Moderate level of discomfort Severe (Grade 3): Unable to perform routine activities Significant level of discomfort Potentially life-threatening (Grade 4): Hospitalization or emergency room (ER) visit for potentially life-threatening event
Time Frame
From first vaccination to 28 days after the third vaccination, 71 days.
Secondary Outcome Measure Information:
Title
Percentage of Participants With a Serum Immunologic Response to Coli Surface Antigen 6 (CS6)
Description
Serum samples were assayed for immunoglobulin G (IgG) and immunoglobulin A (IgA) antibody titers against CS6 using an enzyme-linked Immunosorbent assay (ELISA). Immunologic response was defined as a ≥ 4-fold increase in reciprocal endpoint titer between Baseline and any post-vaccination sample.
Time Frame
Baseline (Day 1 predose), Days 22 and 43 predose, and Day 70
Title
Percentage of Participants With a Serum Immunologic Response to Labile Toxin
Description
Serum samples were assayed for immunoglobulin G (IgG) and immunoglobulin A (IgA) antibody titers against labile toxin using an enzyme-linked Immunosorbent assay (ELISA). Immunologic response was defined as a ≥ 4-fold increase in reciprocal endpoint titer between Baseline and any post-vaccination sample.
Time Frame
Baseline (Day 1 predose), Days 22 and 43 predose, and Day 70
Title
Percentage of Participants With a Mucosal Immunologic Response to Coli Surface Antigen 6 (CS6)
Description
Peripheral blood mononuclear cells (PBMCs) were collected to determine antibody responses from lymphocyte supernatant against CS6 at Baseline and 7 days after each vaccination. Antibody in lymphocyte supernatant (ALS) is an indirect quantification of antibody secreting cells (ASC) activated in the mucosa that circulate in the peripheral blood about seven days post-mucosal immunization/infection. After incubation, lymphocyte supernatant was assayed for antigen-specific IgG and IgA antibodies using ELISA. A positive ALS response was defined as a four-fold rise in antibody titers between Baseline and any post vaccination sample.
Time Frame
Baseline (Day 1 pre-dose), Days 8 and 29 predose, and Day 50
Title
Percentage of Participants With a Mucosal Immunologic Response to Labile Toxin
Description
Peripheral blood mononuclear cells (PBMCs) were collected to determine antibody responses from lymphocyte supernatant against labile toxin at Baseline and 7 days after each vaccination. Antibody in lymphocyte supernatant (ALS) is an indirect quantification of antibody secreting cells (ASC) activated in the mucosa that circulate in the peripheral blood about seven days post-mucosal immunization/infection. After incubation, lymphocyte supernatant was assayed for antigen-specific IgG and IgA antibodies using ELISA. A positive ALS response was defined as a four-fold rise in antibody titers between Baseline and any post vaccination sample.
Time Frame
Baseline (Day 1 pre-dose), Days 8 and 29 predose, and Day 50
Title
Geometric Mean Titer of Serum Anti-CS6 Immunoglobulin G Antibodies
Description
Serum samples were assayed for IgG antibody titers against CS6 using an enzyme-linked Immunosorbent assay (ELISA).
Time Frame
Days 1, 22, and 43 pre-vaccination, and Day 70
Title
Geometric Mean Titer of Serum Anti-CS6 Immunoglobulin A Antibodies
Description
Serum samples were assayed for IgA antibody titers against CS6 using an enzyme-linked Immunosorbent assay (ELISA).
Time Frame
Days 1, 22, and 43 pre-vaccination, and Day 70
Title
Geometric Mean Titer of Serum Anti-LT Immunoglobulin G Antibodies
Description
Serum samples were assayed for IgG antibody titers against labile toxin using an enzyme-linked Immunosorbent assay (ELISA).
Time Frame
Days 1, 22, and 43 pre-vaccination, and Day 70
Title
Geometric Mean Titer of Serum Anti-LT Immunoglobulin A Antibodies
Description
Serum samples were assayed for IgA antibody titers against labile toxin using an enzyme-linked Immunosorbent assay (ELISA).
Time Frame
Days 1, 22, and 43 pre-vaccination, and Day 70
Title
Geometric Mean Titer of Antibody Lymphocyte Supernatant Anti-CS6 Immunoglobulin G Antibodies
Description
Lymphocyte supernatant was assayed for IgG antibody titers against CS6 using ELISA.
Time Frame
Days 1, 8, 29 and 50
Title
Geometric Mean Titer of Antibody Lymphocyte Supernatant Anti-CS6 Immunoglobulin A Antibodies
Description
Lymphocyte supernatant was assayed for IgA antibody titers against CS6 using ELISA.
Time Frame
Days 1, 8, 29, and 50
Title
Geometric Mean Titer of Antibody Lymphocyte Supernatant Anti-LT Immunoglobulin G Antibodies
Description
Lymphocyte supernatant was assayed for IgG antibody titers against labile toxin using ELISA.
Time Frame
Days 1, 8, 29, and 50
Title
Geometric Mean Titer of Antibody Lymphocyte Supernatant Anti-LT Immunoglobulin A Antibodies
Description
Lymphocyte supernatant was assayed for IgA antibody titers against labile toxin using ELISA.
Time Frame
Days 1, 8, 29, and 50

10. Eligibility

Sex
All
Minimum Age & Unit of Time
18 Years
Maximum Age & Unit of Time
45 Years
Accepts Healthy Volunteers
Accepts Healthy Volunteers
Eligibility Criteria
Inclusion Criteria: Healthy, adult, male or female, age 18 to 45 years (inclusive) at the time of enrollment. Completion and review of comprehension test (achieved > 70% accuracy). Signed informed consent document. Available for the required follow-up period and scheduled clinic visits. Women: Negative pregnancy test with understanding (through informed consent process) to not become pregnant during the study or within three (3) months following last vaccination. Exclusion Criteria: Health problems (for example, intercurrent febrile illness, chronic medical conditions such as psychiatric conditions, diabetes mellitus, hypertension or any other condition that might place the subject at increased risk of adverse events) - study clinicians, in consultation with the PI, will use clinical judgment on a case-by-case basis to assess safety risks under this criterion. The PI will consult with the Research Monitor as appropriate. Clinically significant abnormalities on physical examination. Immunosuppressive drugs (use of systemic corticosteroids or chemotherapeutics that may influence antibody development) or illness (including immunoglobulin A [IgA] deficiency, defined by serum IgA < 7 mg/dL). Women who are pregnant or planning to become pregnant during the study period plus three (3) months beyond the last received dose and currently nursing women. Participation in research involving another investigational product (defined as receipt of investigational product or exposure to invasive investigational device) 30 days before planned date of first vaccination or anytime through the last study safety visit. Positive blood test for Hepatitis B surface antigen (HBsAg), Hepatitis C virus (HCV), human immunodeficiency virus (HIV)-1/2. Clinically significant abnormalities on basic laboratory screening. Exclusionary skin disease history/findings that would confound assessment or prevent appropriate local monitoring of adverse events (AEs), or possibly increase the risk of a local AE History of chronic skin disease (clinician judgement) Acute skin infection/eruptions on the upper arms including fungal infections, severe acne or active contact dermatitis Allergies that may increase the risk of AEs Regular use (weekly or more often) of antidiarrheal, anti-constipation, or antacid therapy Abnormal stool pattern (fewer than 3 stools per week or more than 3 stools per day) on a regular basis; loose or liquid stools on other than an occasional basis History of microbiologically confirmed ETEC or cholera infection in the last 3 years Travel to countries where ETEC or V. cholerae or other enteric infections are endemic (most of the developing world) within 3 years prior to dosing (clinician judgement) Symptoms consistent with Travelers' Diarrhea or concurrent with travel to countries where ETEC infection is endemic (most of the developing world) within 3 years prior to dosing, OR planned travel to endemic countries during the length of the study Vaccination for or ingestion of ETEC, cholera, or E. coli heat labile toxin within 3 years prior to dosing Occupation involving handling of ETEC or V. cholerae currently, or in the past 3 years
Overall Study Officials:
First Name & Middle Initial & Last Name & Degree
Tida K Lee, MD, PhD
Organizational Affiliation
Naval Medical Research Center
Official's Role
Principal Investigator
Facility Information:
Facility Name
Walter Reed Army Institute of Research Clinical Trial Center
City
Silver Spring
State/Province
Maryland
ZIP/Postal Code
20910
Country
United States

12. IPD Sharing Statement

Learn more about this trial

Dose Escalating Study of a Prototype CS6 Subunit Vaccine With a Modified Heat-labile Enterotoxin From Enterotoxigenic Escherichia Coli (ETEC)

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