Trial Outcomes & Findings for Immunologic Responses to a Live Attenuated Oral Cholera Vaccine (NCT NCT03251495)

NCT ID: NCT03251495

Last Updated: 2026-02-13

Results Overview

Antibody response is evaluated as the level of antibody titers in serum. Higher vibriocidal antibody titers indicate greater protection against cholera.

Recruitment status

COMPLETED

Study phase

PHASE2

Target enrollment

34 participants

Primary outcome timeframe

Day 1 (pre-vaccination), Day 29

Results posted on

2026-02-13

Participant Flow

Participants were recruited at The Hope Clinic of Emory University in Atlanta, Georgia, USA. Participant enrollment began August 29, 2017 and follow up for the Day 29 study visit concluded on December 10, 2024.

Participant milestones

Participant milestones
Measure
Vaxchora Vaccination
Healthy participants receive a single dose of oral live cholera vaccine. Vaxchora is a live attenuated cholera vaccine that provides immunity against V. cholerae serogroup O1. Participants receive one single oral dose of 100 mL.
Overall Study
STARTED
34
Overall Study
COMPLETED
28
Overall Study
NOT COMPLETED
6

Reasons for withdrawal

Reasons for withdrawal
Measure
Vaxchora Vaccination
Healthy participants receive a single dose of oral live cholera vaccine. Vaxchora is a live attenuated cholera vaccine that provides immunity against V. cholerae serogroup O1. Participants receive one single oral dose of 100 mL.
Overall Study
Lost to Follow-up
4
Overall Study
Withdrawal by Subject
2

Baseline Characteristics

Immunologic Responses to a Live Attenuated Oral Cholera Vaccine

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure
Vaxchora Vaccination
n=34 Participants
Healthy participants receive a single dose of oral live cholera vaccine. Vaxchora is a live attenuated cholera vaccine that provides immunity against V. cholerae serogroup O1. Participants receive one single oral dose of 100 mL.
Age, Categorical
<=18 years
0 Participants
n=41 Participants
Age, Categorical
Between 18 and 65 years
34 Participants
n=41 Participants
Age, Categorical
>=65 years
0 Participants
n=41 Participants
Age, Continuous
33.9 years
STANDARD_DEVIATION 8.5 • n=41 Participants
Sex/Gender, Customized
Female
17 Participants
n=41 Participants
Sex/Gender, Customized
Male
13 Participants
n=41 Participants
Sex/Gender, Customized
Unknown/Not reported
4 Participants
n=41 Participants
Ethnicity (NIH/OMB)
Hispanic or Latino
1 Participants
n=41 Participants
Ethnicity (NIH/OMB)
Not Hispanic or Latino
33 Participants
n=41 Participants
Ethnicity (NIH/OMB)
Unknown or Not Reported
0 Participants
n=41 Participants
Race (NIH/OMB)
American Indian or Alaska Native
1 Participants
n=41 Participants
Race (NIH/OMB)
Asian
1 Participants
n=41 Participants
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
0 Participants
n=41 Participants
Race (NIH/OMB)
Black or African American
11 Participants
n=41 Participants
Race (NIH/OMB)
White
20 Participants
n=41 Participants
Race (NIH/OMB)
More than one race
1 Participants
n=41 Participants
Race (NIH/OMB)
Unknown or Not Reported
0 Participants
n=41 Participants
Region of Enrollment
United States
34 Participants
n=41 Participants

PRIMARY outcome

Timeframe: Day 1 (pre-vaccination), Day 29

Population: This analysis includes participants who provided samples resulting in usable laboratory data for both the Baseline and Day 29 visit.

Antibody response is evaluated as the level of antibody titers in serum. Higher vibriocidal antibody titers indicate greater protection against cholera.

Outcome measures

Outcome measures
Measure
Vaxchora Vaccination
n=26 Participants
Healthy participants receive a single dose of oral live cholera vaccine. Vaxchora is a live attenuated cholera vaccine that provides immunity against V. cholerae serogroup O1. Participants receive one single oral dose of 100 mL.
Level of Antibody Titers in Serum
Day 29
2671 Vibriocidal antibody titer
Standard Deviation 2552.8
Level of Antibody Titers in Serum
Day 1, pre-vaccination
76 Vibriocidal antibody titer
Standard Deviation 80.9

SECONDARY outcome

Timeframe: Day 1 (pre-vaccination), Day 8, Day 29

Population: This analysis includes participants who provided samples resulting in usable laboratory data for both the Baseline and Day 29 visit.

Plasmablasts are collected via blood draw and isolated and assessed for counts by the study team.

Outcome measures

Outcome measures
Measure
Vaxchora Vaccination
n=26 Participants
Healthy participants receive a single dose of oral live cholera vaccine. Vaxchora is a live attenuated cholera vaccine that provides immunity against V. cholerae serogroup O1. Participants receive one single oral dose of 100 mL.
Plasmablast Levels
Day 1, pre-vaccination
2.0 percent of CD19+ lymphocytes
Standard Deviation 1.9
Plasmablast Levels
Day 8
5.3 percent of CD19+ lymphocytes
Standard Deviation 5.5
Plasmablast Levels
Day 29
1.2 percent of CD19+ lymphocytes
Standard Deviation 0.81

SECONDARY outcome

Timeframe: Day 1 (pre-vaccination), Day 8, Day 29

Population: This analysis includes participants who provided samples resulting in usable laboratory data for both the Baseline and Day 29 visit.

Activated B cells are collected via blood draw and isolated and assessed for counts by the study team.

Outcome measures

Outcome measures
Measure
Vaxchora Vaccination
n=26 Participants
Healthy participants receive a single dose of oral live cholera vaccine. Vaxchora is a live attenuated cholera vaccine that provides immunity against V. cholerae serogroup O1. Participants receive one single oral dose of 100 mL.
Activated B Cell Levels
Day 8
0.7 percent of CD19+ lymphocytes
Standard Deviation 0.5
Activated B Cell Levels
Day 29
0.7 percent of CD19+ lymphocytes
Standard Deviation 0.6
Activated B Cell Levels
Day 1, pre-vaccination
0.8 percent of CD19+ lymphocytes
Standard Deviation 0.6

SECONDARY outcome

Timeframe: Day 1 (pre-vaccination), Day 29

Population: This analysis includes participants who provided samples resulting in usable laboratory data for both the Baseline and Day 29 visit.

Memory B cells are collected via blood draw and isolated and assessed for counts by the study team. The level of memory B cells is evaluated as the percentage of antigen specific immunoglobulin (Ig) secreting cells divided by the total Ig secreting cells.

Outcome measures

Outcome measures
Measure
Vaxchora Vaccination
n=26 Participants
Healthy participants receive a single dose of oral live cholera vaccine. Vaxchora is a live attenuated cholera vaccine that provides immunity against V. cholerae serogroup O1. Participants receive one single oral dose of 100 mL.
Memory B Cell Levels
Day 1, pre-vaccination
NA % antigen specific cells/total cells
Standard Deviation NA
undetectable level
Memory B Cell Levels
Day 29
NA % antigen specific cells/total cells
Standard Deviation NA
undetectable level

SECONDARY outcome

Timeframe: Day 8

Population: This analysis includes a subset of participants.

The number of antigen-specific monoclonal antibodies (mAbs) was assessed in a subset of participants on Day 8 post-vaccination. Peripheral blood mononuclear cells (PBMCs) were isolated, and antigen-specific plasmablasts were single-cell sorted using fluorescently labeled V. cholerae antigens (e.g., CTB and LPS). Paired immunoglobulin heavy and light chain variable regions were amplified by RT-PCR, cloned into expression vectors, and expressed in mammalian cells. The number of unique antigen-specific monoclonal antibodies was determined by binding assays (e.g., ELISA).

Outcome measures

Outcome measures
Measure
Vaxchora Vaccination
n=149 Total monoclonals
Healthy participants receive a single dose of oral live cholera vaccine. Vaxchora is a live attenuated cholera vaccine that provides immunity against V. cholerae serogroup O1. Participants receive one single oral dose of 100 mL.
Number of Monoclonal Antibodies Produced Per Participant
24.83 monoclonal antibodies (mAbs)
Standard Deviation 6.80

SECONDARY outcome

Timeframe: Day 8

Population: This analysis includes a subset of participants.

The monoclonal antibodies obtained were characterized as cholera toxin B (CTB) specific monoclonals and lipopolysaccharide (LPS) specific monoclonals. The characterization of monoclonal antibodies against V. cholerae is assessed in a subset of participants.

Outcome measures

Outcome measures
Measure
Vaxchora Vaccination
n=65 Total CTB specific monoclonals
Healthy participants receive a single dose of oral live cholera vaccine. Vaxchora is a live attenuated cholera vaccine that provides immunity against V. cholerae serogroup O1. Participants receive one single oral dose of 100 mL.
Number of Cholera Toxin B (CTB) Specific Monoclonals and Lipopolysaccharide (LPS) Specific Monoclonal Antibodies Per Participant
Cholera Toxin B (CTB) specific monoclonals
1.67 monoclonal antibodies (mAbs)
Standard Deviation 2.34
Number of Cholera Toxin B (CTB) Specific Monoclonals and Lipopolysaccharide (LPS) Specific Monoclonal Antibodies Per Participant
Lipopolysaccharide (LPS) specific monoclonals
9.17 monoclonal antibodies (mAbs)
Standard Deviation 7.73

SECONDARY outcome

Timeframe: Up to Day 8, Up to Day 29

The number of solicited and unsolicited adverse events were collected.

Outcome measures

Outcome measures
Measure
Vaxchora Vaccination
n=34 Participants
Healthy participants receive a single dose of oral live cholera vaccine. Vaxchora is a live attenuated cholera vaccine that provides immunity against V. cholerae serogroup O1. Participants receive one single oral dose of 100 mL.
Number of Adverse Events
Days 1 - 8
77 count of events
Number of Adverse Events
Days 9 - 29
1 count of events

SECONDARY outcome

Timeframe: Up to Day 365

The number of serious adverse events were collected during the duration of the study.

Outcome measures

Outcome measures
Measure
Vaxchora Vaccination
n=34 Participants
Healthy participants receive a single dose of oral live cholera vaccine. Vaxchora is a live attenuated cholera vaccine that provides immunity against V. cholerae serogroup O1. Participants receive one single oral dose of 100 mL.
Number of Serious Adverse Events
Up to Day 29
0 count of events
Number of Serious Adverse Events
Day 30 to Day 365
1 count of events

Adverse Events

Vaxchora Vaccination

Serious events: 1 serious events
Other events: 19 other events
Deaths: 0 deaths

Serious adverse events

Serious adverse events
Measure
Vaxchora Vaccination
n=34 participants at risk
Healthy participants receive a single dose of oral live cholera vaccine. Vaxchora is a live attenuated cholera vaccine that provides immunity against V. cholerae serogroup O1. Participants receive one single oral dose of 100 mL.
Cardiac disorders
Hypertension urgency
2.9%
1/34 • Information on adverse events was collected beginning at the baseline assessment and continued through Day 29 (for a total of 29 days). Information on serious adverse events was collected up to Day 365 (for a total of 365 days).

Other adverse events

Other adverse events
Measure
Vaxchora Vaccination
n=34 participants at risk
Healthy participants receive a single dose of oral live cholera vaccine. Vaxchora is a live attenuated cholera vaccine that provides immunity against V. cholerae serogroup O1. Participants receive one single oral dose of 100 mL.
Gastrointestinal disorders
Diarrhea
26.5%
9/34 • Information on adverse events was collected beginning at the baseline assessment and continued through Day 29 (for a total of 29 days). Information on serious adverse events was collected up to Day 365 (for a total of 365 days).
General disorders
Headache
32.4%
11/34 • Information on adverse events was collected beginning at the baseline assessment and continued through Day 29 (for a total of 29 days). Information on serious adverse events was collected up to Day 365 (for a total of 365 days).
General disorders
Fatigue
23.5%
8/34 • Information on adverse events was collected beginning at the baseline assessment and continued through Day 29 (for a total of 29 days). Information on serious adverse events was collected up to Day 365 (for a total of 365 days).
Gastrointestinal disorders
Abdominal pain
17.6%
6/34 • Information on adverse events was collected beginning at the baseline assessment and continued through Day 29 (for a total of 29 days). Information on serious adverse events was collected up to Day 365 (for a total of 365 days).
General disorders
Lack of appetite
5.9%
2/34 • Information on adverse events was collected beginning at the baseline assessment and continued through Day 29 (for a total of 29 days). Information on serious adverse events was collected up to Day 365 (for a total of 365 days).
Cardiac disorders
Tachycardia
2.9%
1/34 • Information on adverse events was collected beginning at the baseline assessment and continued through Day 29 (for a total of 29 days). Information on serious adverse events was collected up to Day 365 (for a total of 365 days).
Skin and subcutaneous tissue disorders
Bruise
2.9%
1/34 • Information on adverse events was collected beginning at the baseline assessment and continued through Day 29 (for a total of 29 days). Information on serious adverse events was collected up to Day 365 (for a total of 365 days).
Gastrointestinal disorders
Gastritis
2.9%
1/34 • Information on adverse events was collected beginning at the baseline assessment and continued through Day 29 (for a total of 29 days). Information on serious adverse events was collected up to Day 365 (for a total of 365 days).
Gastrointestinal disorders
Nausea/vomiting
17.6%
6/34 • Information on adverse events was collected beginning at the baseline assessment and continued through Day 29 (for a total of 29 days). Information on serious adverse events was collected up to Day 365 (for a total of 365 days).

Additional Information

Nadine Rouphael, MD

Emory University

Phone: 404-712-1370

Results disclosure agreements

  • Principal investigator is a sponsor employee
  • Publication restrictions are in place