Typhoid
Conditions
Keywords
Typhoid, Vi-DT, Conjugate vaccine, First in human, New vaccine
Brief summary
This is a randomized, observer-blinded Phase 2 study in healthy infants and toddlers 6-23 months of age at the time of the first vaccine dose. The purpose of this study is to assess the safety and immunogenicity of the Vi-DT vaccine in age group 6-23months of age. The Vi-DT vaccine is administered at 25 µg either as a single dose, or two doses given 6 months apart.
Detailed description
This study is carried out in healthy children aged 6 to 23 months at a single site. A total of 285 participants are enrolled, 114, 114 and 57 participants are randomized to either the single dose, two-dose Vi-DT regimens or placebo/comparator group, respectively within age strata. Three age strata is 6 to less than 9 months, 9 to 12 months and 13 to 23 months. The investigators allow the 9-12 months old children to receive Measles-Mumps-Rubella (MMR) vaccine concomitantly with Vi-DT vaccine and descriptive analysis of immune response to MMR only and to MMR and Vi-DT vaccines are performed to assess the possible immunological interference with MMR vaccine.
Interventions
Manufacturer: SK Bioscience Co., Ltd. Ingredient: Purified Vi-polysaccharide conjugated to diphtheria toxoid Dose: 0.5 mL/Vial
Manufacturer: Sanofi Pasteur Dose: 0.25 ml \*Participants who have not been vaccinated for flu before, will receive a second dose of flu-vaccine after unblinding.
Manufacture: Euro-Med Inc. Dose: 0.5 mL
Sponsors
Study design
Masking description
Observer Blinded
Intervention model description
Participants age 6-23 months
Eligibility
Inclusion criteria
* Healthy infants and children 6-23 months of age at enrollment as determined by medical history, physical examination and clinical judgment of the investigator * Birth weight ≥ 2500 g * ≥ 37 weeks of pregnancy or judge to be full-term by the midwife or birth attendant * Parents aged 18 years and above and legal guardians aged 21 years and above as per the legal authorization in the Philippines, who have voluntarily given informed consent * Parents/ legal guardians willing to follow the study procedures of the study and available for the entire duration of the study
Exclusion criteria
* Child with a congenital abnormality * Subject with abnormal routine biological values at screening * Subject concomitantly enrolled or scheduled to be enrolled in another trial * Acute illness, in particular infectious disease or fever (axillary temperature ≥37.5°C), within three days prior to enrolment and vaccination * Known history of immune function disorders including immunodeficiency diseases, or chronic use of systemic steroids (\>20 mg/day prednisone equivalent for periods exceeding 10 days), cytotoxic or other immunosuppressive drugs * Child with a previously ascertained or suspected disease caused by S. typhi * Child who have had household contact with/and or intimate exposure to an individual with laboratory-confirmed S. typhi * Known history or allergy to vaccines or other medications * Know history of allergy to eggs, chicken protein, neomycin and formaldehyde * History of uncontrolled coagulopathy or blood disorders * Mother has known HIV infection or other immune function disorders * 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 * Child whose parents or legal guardian planning to move from the study area before the end of study period
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Safety endpoints: solicited and unsolicited adverse events and serious adverse events | Solicited AE: during 7 days after each vaccination. Unsolicited AE: after the first vaccination until 4 weeks after the second vaccination. SAE will be captured after the first vaccination up to week 100 for Group A, week 96 for Group B, week 36 Group C | * Frequency (percentage) of solicited local reactions at the injection site: Pain, tenderness, erythema/redness, swelling/induration and pruritus local * Frequency (percentage) of solicited systemic reactions: Fever, lethargy, irritability, vomiting, diarrhea, drowsiness, loss of appetite, persistent crying, rash and nasopharyngitis * Frequency (percentage) of unsolicited adverse events * Frequency (percentage) of serious adverse events |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Immunogenicity Endpoints | At week 28, 4 weeks after the second vaccination | Seroconversion rate of anti-Vi IgG by Geometric Mean Titers (GMT) will be measured 4 weeks after the second vaccination using an in-house ELISA assay using standardized reagents and reference serum. The level of the specific anti-Vi IgG in ELISA units for each serum sample is determined by comparison to a reference serum. The number of anti-Vi IgG positive sera will be used to calculate the seroconversion rates. |
Other
| Measure | Time frame | Description |
|---|---|---|
| Exploratory Endpoints | At week 4, 4 week after MMR vaccination | Seroconversion rates of Measles, Mumps and Rubella will be determined 4 week after MMR vaccination. Serum titers will be measured by routinely used commercially available ELISA kits. Kit-specific threshold of positivity will be used to determine specific seroconversion rates. |
Countries
Philippines