Clinical trial NCT06466629: The Optimal Timing of Vaccination in Pregnancy
Official title: The Optimal Timing of Vaccination in Pregnancy: a Multi-dimensional Mechanistic Approach to Measure Immune Responses in Pregnant Women
Study type: OBSERVATIONAL
Overall status: RECRUITING
Conditions: Pertussis/Whooping Cough
Lead sponsor: Universiteit Antwerpen
Sponsor class: OTHER
Collaborators: name: Université Libre de Bruxelles
First posted: 2024-06-20
Enrollment: 96
Sex: FEMALE
Minimum age (years): 18
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Observational model: COHORT
Time perspective: PROSPECTIVE
Sampling method: NON_PROBABILITY_SAMPLE
Study population: Female pregnant population within Flanders

Brief summary: The central aim of this study is to investigate the optimal timing of vaccination in pregnant women. Therefore, pregnant women will be vaccinated against pertussis at different timepoints and blood and breast milk samples will be taken at several timepoints. The main objectives are to assess the impact of timing on humoral and cellular immune responses in pregnant women, on antibody characteristics transferred across the placenta and on transplacental transport efficiency. The impact of maternal pertussis vaccination and timing of maternal pertussis vaccination on breastmilk antibody composition will also be investigated, as well as the impact of vaccination during pregnancy on the mucosal uptake of breastmilk IgA antibodies by the infant respiratory and gastrointestinal tract.


Eligibility criteria: Inclusion Criteria:

* Ability to provide informed consent.
* Willing to be vaccinated with a Tdap vaccine during pregnancy.
* Intend to be available for follow-up visits and phone call access until 6 months postpartum.
* Influenza and COVID-19 vaccination during pregnancy (as per Belgian recommendations) is allowed.

Exclusion Criteria:

* Vaccinated with an aP containing vaccine during the last 5 years
* Significant mental illness (e.g. schizophrenia, psychosis, major depression)
* Serious underlying immunological condition (e.g. immunosuppressive disease or therapy, human immunodeficiency virus (HIV) infection...).
* Systemic treatment with immune suppressive medication, including chronic steroid use of \> 10 mg prednisone or equivalent.
* Anything in the opinion of the investigator that would prevent volunteers from completing the study or put the volunteer at risk.
* Previous severe reaction to any vaccine
* High risk for serious obstetrical complications.

Primary outcomes:
measure: Measurement of antibody levels, subclass antibody levels, antibody glycosylation and antibody functionality in maternal blood after Tdap vaccination at different timings in pregnancy.
timeFrame: Before Tdap vaccination
measure: Measurement of antibody levels, subclass antibody levels, antibody glycosylation and antibody functionality in maternal blood after Tdap vaccination at different timings in pregnancy.
timeFrame: One month after Tdap vaccination
measure: Measurement of antibody levels, subclass antibody levels, antibody glycosylation and antibody functionality in maternal blood after Tdap vaccination at different timings in pregnancy.
timeFrame: At delivery
measure: Measurement of antibody levels, subclass antibody levels, antibody glycosylation and antibody functionality in maternal blood after Tdap vaccination at different timings in pregnancy.
timeFrame: 6 months postpartum
Secondary outcomes:
measure: Measurement of cytokine levels and T-cell subsets in maternal blood after Tdap vaccination at different timings in pregnancy.
timeFrame: Before Tdap vaccination
measure: Measurement of cytokine levels and T-cell subsets in maternal blood after Tdap vaccination at different timings in pregnancy.
timeFrame: One month after Tdap vaccination
measure: Measurement of cytokine levels and T-cell subsets in maternal blood after Tdap vaccination at different timings in pregnancy.
timeFrame: At delivery
measure: Measurement of cytokine levels and T-cell subsets in maternal blood after Tdap vaccination at different timings in pregnancy.
timeFrame: 6 months postpartum
measure: Measurement of antibody levels in cord blood at delivery after Tdap vaccination at different timings in pregnancy to calculate the transport of antibodies across the placenta
timeFrame: At delivery
measure: Measurement of antibody levels, subclass antibody levels, antibody glycosylation and antibody functionality in breastmilk after Tdap vaccination at different timings in pregnancy.
timeFrame: 6 months postpartum
Other outcomes:
Locations:
city: Edegem
country: Belgium
facility: Vaccinopolis
state: Antwerp
Study officials:
References: