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Immune Non-inferiority and Safety of a Vi-DT Typhoid Conjugate Vaccine

Phase 3
Conditions
Typhoid
Interventions
Biological: Test Vaccine Vi-DT Typhoid conjugate
Biological: Control Vaccine Typbar TCV®
Registration Number
NCT03933098
Lead Sponsor
International Vaccine Institute
Brief Summary

This is a Multicenter, observer-blinded, randomized, Active controlled, Phase 3 study in healthy 6 months to 45 years aged Nepalese at the time of the first vaccine dose.

The study objectives are:

I. Demonstrate non-inferiority of Vi-DT compared to Typbar TCV® as measured by seroconversion rates of anti-Vi IgG ELISA antibody titers, 4 weeks after single dose (pooled immunogenicity of three lots of Vi-DT)

II. Demonstrate the equivalence of immunogenicity as measured by anti-Vi IgG GMT of three lots of Vi-DT vaccine 4 weeks after single dose.

Detailed Description

Subjects will be stratified according to age. The study procedure is as follows:

Visit 1 (day-1 to -7): Screen participants by medical/medications history, physical examination, Vital signs, Urine pregnancy test (UPT)

Visit 2 (day 0): Enroll, randomize and administer vaccine to eligible participants and assess participant safety by physical examination and Vital signs, Collect blood for immunogenicity assessments.

Visit 3 (day 7): Check solicited adverse reaction 7 days post vaccination and Assess participant safety by physical examination and Vital signs

Visit 4 (day 28): Assess participant safety by physical examination and Vital signs, Collect blood for immunogenicity assessments

Visit 5 (day 84): Assess participant safety by physical examination and Vital signs

Visit 6 (day 168): Assess participant safety by physical examination and Vital signs, Collect blood for immunogenicity assessments, and fill in study completion form in the absence of any safety concern.

This study is observer-blind: vaccine administrator and vaccine safety evaluator will be two distinct persons to avoid bias of safety assessment. Trial staff other than the vaccine administrator.

For retention: After vaccination, field health worker/designee will contact participant every day till Day 7 by physical visit or by phone call. Follow-up reminder calls will be done very frequently as per discretion of study staff until 24 weeks for all participant to assess participant safety.

Recruitment & Eligibility

Status
UNKNOWN
Sex
All
Target Recruitment
1800
Inclusion Criteria
  1. Healthy participants 6 months to 45 years of age at enrollment
  2. Participants/Parents/LAR who have voluntarily given informed consent/assent
  3. Participants/Parents/LAR willing to follow the study procedures of the study and available for the entire duration of the study
Exclusion Criteria
  1. Child with a congenital abnormality

  2. Subject concomitantly enrolled or scheduled to be enrolled in another trial

  3. Known history of immune function disorders including immunodeficiency diseases (Known HIV infection or other immune function disorders)

  4. Chronic use of systemic steroids (>2 mg/kg/day or >20 mg/day prednisone equivalent for periods exceeding 10 days), cytotoxic or other immunosuppressive drugs

  5. Receipt of blood or blood-derived products in the past 3 months

  6. Subject with a previously ascertained or suspected disease caused by S. Typhi

  7. Subject who have had household contact with/and or intimate exposure to an individual with laboratory-confirmed S. Typhi

  8. Individual who has previously received a typhoid vaccine

  9. Subject who has received or is expected to receive other vaccines from 1 month prior to IP vaccination to Visit 4 (approx.1 month post IP) except PVC booster as per EPI schedule

  10. Known history or allergy to vaccines or other medications

  11. History of uncontrolled coagulopathy or blood disorders

  12. Any abnormality or chronic disease which in the opinion of the investigator might be detrimental for the safety of the subject and interfere with the assessment of the study objectives

  13. Any female participant who is lactating, pregnant* or planning for pregnancy during the course of study period

  14. Participants/Parents/LAR planning to move from the study area before the end of study period

  15. As per Investigator's medical judgement individuals could be excluded from the study inspite of meeting all inclusion/exclusion criteria mentioned above

    Temporary Contraindication

  16. Acute illness, in particular infectious disease or fever (axillary temperature ≥37.5°C), within three days prior to enrolment and vaccination.

    • Urine pregnancy test (UPT) will be performed in all married females prior to injection

Study & Design

Study Type
INTERVENTIONAL
Study Design
PARALLEL
Arm && Interventions
GroupInterventionDescription
Test group A: Lot 1 Vi-DT (typhoid conjugate vaccine)Test Vaccine Vi-DT Typhoid conjugateOne dose of Vi-DT (typhoid conjugate vaccine) Lot 1 will be administrated intramuscularly at Enrollment visit (Day 0). MR for age group at 9-15 months.
Test group B: Lot 2 Vi-DT (typhoid conjugate vaccine)Test Vaccine Vi-DT Typhoid conjugateOne dose of Vi-DT (typhoid conjugate vaccine) Lot 2 will be administrated intramuscularly at Enrollment visit (Day 0). MR for age group at 9-15 months.
Test group C: Lot 3 Vi-DT (typhoid conjugate vaccine)Test Vaccine Vi-DT Typhoid conjugateOne dose of Vi-DT (typhoid conjugate vaccine) Lot 3 will be administrated intramuscularly at Enrollment visit (Day 0). MR for age group at 9-15 months.
Test group D: Typbar TCVControl Vaccine Typbar TCV®One dose of Typbar TCV will be administrated intramuscularly at Enrollment visit (Day 0). MR for age group at 9-15 months.
Primary Outcome Measures
NameTimeMethod
Seroconversion rate14 weeks (28 days) after vaccination of Vi-DT(pooled)/ Typbar TCV® compared to baseline (D0)

Defined as a 4-fold increase of serum anti-Vi IgG antibody titer

Geometric Mean Titers (GMT)14 weeks after vaccination of Vi-DT

Measurement of the Geometric Mean Titers (GMT) following 4 weeks after vaccination of three lots of Vi-DT

Secondary Outcome Measures
NameTimeMethod
Geometric Mean Titers (GMT) 24 weeks and 24 weeks after vaccination of Vi-DT(pooled)/ Typbar TCV®

Measurement of the Geometric Mean Titers (GMT) following 4 weeks (28 days) and 24 weeks(168 days) after vaccination of Vi-DT (pooled)/ Typbar TCV®

Seroconversion rate 224 weeks (168 days) after vaccination of Vi-DT(pooled)/ Typbar TCV® compared to baseline (D0).

Defined as a 4-fold increase of serum anti-Vi IgG antibody titer

Seroconversion rate 34 weeks (28 days) after vaccination of Vi-DT(pooled)

Definded as a Seroconversion rates of anti-Vi IgG ELISA antibody titers after vaccination of three lots of Vi-DT.

Seroconversion rate 44 weeks (28 days) after vaccination of Vi-DT(pooled)

Definded as a Seroconversion rates of anti-Vi IgG ELISA antibody titers at 4 weeks (28 days) after vaccination of three lots of Vi-DT in each age strata

Seroconversion rate 54 weeks (28 days) after vaccination of MR compared to baseline (D0)

Definded as IgG ELISA antibody titers for Measles (M), and Rubella (R) following single dose of MR a vaccine at baseline D0 and 4 weeks

Safety endpoints for solicited adverse events (reactogenicity)7days after vaccination of Vi-DT(pooled)/ Typbar TCV®

Proportion of participants with local and systemic solicited adverse events

Trial Locations

Locations (4)

Nepalgunj medical college

🇳🇵

Banke, City- Nepalgunj, Nepal

Dhulikhel Hospital

🇳🇵

Kavre, Dhulikhel, Nepal

Kanti Children's Hospital

🇳🇵

Kathmandu, Sukedhara, Nepal

B.P.Koirala Institute of Health Sciences

🇳🇵

Rautahat, Dharan, Nepal

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