A Phase 1 interventional study of OSP:rTTHc Cholera Conjugate Vaccine Cohort A and OSP:rTTHc Cholera Conjugate Vaccine with Aluminum phosphate adjuvant Cohort A in Cholera Vaccination Reaction, sponsored by International Vaccine Institute. Completed at 3 sites in Korea, Republic of. Open to participants aged 19 Years to 45 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2025-03-25.
Sponsored by International Vaccine Institute · Phase 1, Interventional, and Prevention
This Phase I, first-in-human study is intended to primarily determine the safety of the dose range with or without Aluminum phosphate adjuvant expected to be needed for later clinical studies, to determine the nature of adverse reactions (i.e., safety profile) and to secondly assess the Aluminum phosphate humoral immune responses in non-endemic population to guide future dose selection.
A total of 150 eligible participants will be recruited in 3 sequential dose cohorts: low-dose 5 µg, medium-dose 10 µg, and high-dose 25 µg. In each dose cohorts, the participants will be randomized in a blinded manner into three arms (vaccine antigen with aluminum phosphate, vaccine antigen without Aluminum phosphate or placebo) in 2:2:1 ratio. All the participants will receive two intramuscular injections of 0.5 mL of the designated study vaccine or placebo on deltoid muscle, on Days 0 and 28.
The DSMB will review the safety data and approve dose escalation before investigational product injection of the next cohort is initiated.
The study primary objective is to evaluate the safety of the O Specific Polysaccharide recombinant Tetanus Toxoid Heavy Chain Fragment (OSP:rTTHc) cholera conjugate vaccine (CCV) after each dose vaccination.
The secondary objectives are:
The exploratory objectives are:
83 studies on the registry are indexed under Cholera; 16 are open to participants now.
This study's enrollment of 150 is below the median of 262 across 72 interventional studies indexed under Cholera.
Browse Cholera studies →International Vaccine Institute is the lead sponsor of 47 studies on the registry; 12 are open to participants now.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).
Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
The other ingredients in a medicine besides the active drug, such as fillers, colours or preservatives.
The human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.
A weakened immune system. It can come from an illness, such as HIV or some blood cancers, or from medicines that turn the immune system down, for example after an organ transplant or for an autoimmune disease; steroids at higher doses count.
Read whether the line is about a condition or about medicines, and which medicines and doses it means.
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Childbearing potential
Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).
Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraception
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Investigational drug or device
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Excipients
The other ingredients in a medicine besides the active drug, such as fillers, colours or preservatives.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
HIV
The human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Corticosteroids (steroids)
Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Immunosuppression
A weakened immune system. It can come from an illness, such as HIV or some blood cancers, or from medicines that turn the immune system down, for example after an organ transplant or for an autoimmune disease; steroids at higher doses count.
Read whether the line is about a condition or about medicines, and which medicines and doses it means.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraindication
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
BMI (body mass index)
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
2 doses @0.5 mL of test vaccine administered intramuscularly in deltoid region at 4 weeks apart
Biological: OSP:rTTHc Cholera Conjugate Vaccine Cohort A · Biological: OSP:rTTHc Cholera Conjugate Vaccine Cohort B · Biological: OSP:rTTHc Cholera Conjugate Vaccine Cohort C
2 doses @0.5 mL of test vaccine administered intramuscularly in deltoid region at 4 weeks apart
Biological: OSP:rTTHc Cholera Conjugate Vaccine with Aluminum phosphate adjuvant Cohort A · Biological: OSP:rTTHc Cholera Conjugate Vaccine with Aluminum phosphate adjuvant Cohort B · Biological: OSP:rTTHc Cholera Conjugate Vaccine with Aluminum phosphate adjuvant Cohort C
2 doses @0.5 mL of Sterile 0.9% sodium chloride administered intramuscularly in deltoid region at 4 weeks apart
Other: Placebo Cohort A · Other: Placebo Cohort B · Other: Placebo Cohort C
OSP:rTTHc Cholera Conjugate Vaccine without Aluminum phosphate with dose formulation 5 µg of OSP:rTTHc
OSP:rTTHc Cholera Conjugate Vaccine with Aluminum phosphate with dose formulation 5 µg of OSP:rTTHc
Sterile 0.9% sodium chloride
OSP:rTTHc Cholera Conjugate Vaccine without Aluminum phosphate with dose formulation 10 µg of OSP:rTTHc
OSP:rTTHc Cholera Conjugate Vaccine with Aluminum phosphate with dose formulation 10 µg of OSP:rTTHc
Sterile 0.9% sodium chloride
OSP:rTTHc Cholera Conjugate Vaccine without Aluminum phosphate with dose formulation 25 µg of OSP:rTTHc
OSP:rTTHc Cholera Conjugate Vaccine with Aluminum phosphate with dose formulation 25 µg of OSP:rTTHc
Sterile 0.9% sodium chloride
Serious adverse events (SAEs) and adverse events of special interest (AESIs)
Occurrence of any SAEs/AESIs from the time of the first dose of study vaccine
Time frame: Entire study participation period (approximately 7 months)
Immediate adverse events
Occurrence of immediate adverse events within 30 minutes from the time of each study vaccination.
Time frame: Within 30 minutes post each dose
Solicited adverse events
Occurrence of solicited injection site and solicited systemic adverse events from the time of each study vaccination through 7 days after each study vaccination
Time frame: Within 7 days post each dose
Unsolicited adverse events
Occurrence of unsolicited adverse events from the time of each study vaccination through 28 days after each study vaccination.
Time frame: Within 28 days post each dose
Clinical safety laboratory parameters
Occurrence of clinically significant changes in clinical safety laboratory parameters from the time of each vaccination through 28 days after each study vaccination.
Time frame: Within 28 days post each dose
Seroconversion rates of IgG antibody responses to OSP
Proportion of participants achieving seroconversion (defined as a 4-fold increase of serum anti-OSP IgG antibody titer at approximately 28 days after the first and second dose of investigational product compared to baseline
Time frame: Baseline and at 28 days post the first and second dose
Geometric Mean Titers (GMTs) of serum anti-OSP IgG
GMTs of serum anti-OSP IgG antibodies at 28 days after the first and second dose of investigational product compared to baseline
Time frame: Baseline and at 28 days post the first and second dose
Geometric Mean Fold Rise (GMFR) of serum anti-OSP IgG
GMFR of serum anti-OSP IgG antibodies at 28 days after the first and second dose of investigational product
Time frame: At 28 days post the first and second dose
Seroconversion rates of serum vibriocidal antibody titers
Proportion of participants with a 4-fold or greater rises in serum vibriocidal antibody titers against V. cholerae O1 Inaba and V. cholerae O1 Ogawa, relative to baseline, 28 days after the first and second dose of investigational product compared to baseline
Time frame: Baseline and at 28 days post the first and second dose
GMT of serum vibriocidal antibody titers
Geometric Mean Titers (GMT) of serum vibriocidal antibody titers against V. cholerae O1 Inaba and V. cholerae O1 Ogawa at 28 days after the first and second dose of investigational product compared to baseline .
Time frame: Baseline and at 28 days post the first and second dose
GMFR of serum vibriocidal antibody titers
GMFR of serum vibriocidal antibody titers against V. cholerae O1 Inaba and V. cholerae O1 Ogawa at 28 days after the first and second dose of investigational product
Time frame: At 28 days post the first and second dose
Seroconversion of serum anti-TT antibody titer
Proportion of participants achieving seroconversion (defined as at least 4-fold increase) of serum anti-TT antibody titer at 28 days after first and second dose vaccination compared to baseline
Time frame: Baseline and at 28 days post the first and second dose
Memory B Cell responses
Memory B Cell responses measured by Elispot assay at 28 days after the first dose vaccination and 6 months after second dose vaccination compared to baseline.
Time frame: Baseline, 28 days, and 6 months
Plan to share: No
No publications or documents are linked to this record.
Ran from Dec 2022 to primary completion in Sep 2023, 9 months.
How these figures are worked out, and which studies are left out of them.
This study is completed, as verified in Mar 2025. You cannot join it, but the record below documents what was studied.
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