Persistence and Long-Term Protection of Vi Antibodies Induced by Vi-DT Conjugate Vaccines in Indonesian

Study Overview
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Brief Summary
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Vi-DT Typhoid vaccine is a novel vaccine. This study will be done to know the long-term protection and persistent antibody by measured the antibody titer after 2,3,4 and 5 years after immunization.

Detailed Description
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This study will be done to know the long-term protection and persistent antibody, by measured the antibody titer after 2,3,4 and 5 years after immunization.

Official Title
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Persistence and Long-Term Protection of Vi Antibodies Induced by Vi-DT Conjugate Vaccines in Indonesian Adults, Adolescent, Children and Infants

Conditions
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Vaccine

Intervention / Treatment
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* Drug: Vi-DT Typhoid Conjugate Vaccine


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Healthy. Subject who completed the phase II Vi-DT study (Typhoid 0218) Subjects/Parents have been informed properly regarding the study and signed the informed consent form. Subject/parents/legal guardians will commit to comply with the instructions of the investigator and the schedule of the trial. Exclusion Criteria: Subject concomitantly enrolled or scheduled to be enrolled in another trial. Evolving mild, moderate or severe illness, especially infectious diseases or fever (axillary temperature ≥ 37.5oC). Known history of allergy to any component of the vaccines. History of uncontrolled coagulopathy or blood disorders contraindicating intramuscular injection. Any abnormality or chronic disease which according to the investigator might be compromised by the vaccination and/or interfere with the assessment of the trial objectives.

Ages Eligible for Study
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Minimum Age: 6 Months
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
Intervention Model: Single Group Assignment
Interventional Model Description: One dose Vi-DT vaccine in clinical trial subjects which is received primary dose at 6-23 months old.
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Vi-DT Typhoid Conjugate Vaccine<br>Participants receive 1 dose (0.5ml) Vi-DT Typhoid Conjugate Vaccine, intramuscularly. | Drug: Vi-DT Typhoid Conjugate Vaccine<br>* Typhoid Conjugate Vaccine<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| To evaluate antibody persistence 2 years after vaccination with one dose of Vi-DT in adults, adolescent, children and infants | Percentage of adults, adolescent, children and infants with seroconversion defined as >= 4 fold in antibody titer of anti Vi IgG 2 years after vaccination compared to baseline. | 2 years + 2 months after primary dose | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| To evaluate immunogenicity one month after booster dose of Vi-DT in subject aged 6-23 months when receiving the primary dose. | Percentage of subject aged 6-23 months old at primary dose with seroconversion defined as >= 4 fold in antibody titer 28 days after booster dose compared to pre booster dose. | 28 days (-4/+14D) | 
| To assess the safety following booster vaccination in subject aged 6-23 months when receiving the primary dose. | Percentage of subject with at least one adverse event, solicited or unsolicited, within 30 minutes, 72hours, 7 days and 28 days after booster dose. | 28 days (-4/+14D) | 
| To evaluate antibody persistence 3, 4 and 5 years after vaccination with one dose of Vi-DT in adults, adolescents, and children groups. | Percentage of adults, adolescents and children with seroconversion defined as ≥ 4-fold in antibody titer of anti-Vi IgG 3,4 and 5 years after vaccination compared to baseline. | 5 years | 
| To evaluate antibody persistence 1, 2 and 3 years after booster vaccination in subject aged 6-23 months when receiving the primary dose. | Percentage of adults, adolescents and children with seroconversion defined as ≥ 4-fold in antibody titer of anti-Vi IgG 3,4 and 5 years after vaccination compared to before booster. | 3 years | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Vi-DT Typhoid Conjugate Vaccine