The Optimal Timing of Vaccination in Pregnancy

Recruiting

• Conditions: Pertussis/Whooping Cough
• Interventions: Biological: Triaxis, Sanofi Pasteur

• Registration Number: NCT06466629
• Lead Sponsor: Elke Leuridan, MD, PhD

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.

Detailed Description

Not available

Study Timeline

• Study Start: 2021-07-01
• Study First Submitted: 2022-11-16
• Status Verified: 2024-06
• Study First Submitted QC: 2024-06-13
• Last Update Submitted: 2024-06-13
• Study First Posted: 2024-06-20
• Last Update Posted: 2024-06-20
• Primary Completion: 2024-10-31
• Study Completion: 2025-04-30

Recruitment & Eligibility

• Status: RECRUITING
• Sex: Female
• Target Recruitment: 96

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.

Study & Design

• Study Type: OBSERVATIONAL
• Study Design: Not specified

Arm && Interventions

Group	Intervention	Description
Cohort 2	Triaxis, Sanofi Pasteur	Pregnant women vaccinated with Tdap vaccine between 25-27 weeks of gestation
Cohort 3	Triaxis, Sanofi Pasteur	Pregnant women vaccinated with Tdap vaccine between 34-36 weeks of gestation
Cohort 1	Triaxis, Sanofi Pasteur	Pregnant women vaccinated with Tdap vaccine between 16-18 weeks of gestation

Primary Outcome Measures

Name	Time	Method
Measurement of antibody levels, subclass antibody levels, antibody glycosylation and antibody functionality in maternal blood after Tdap vaccination at different timings in pregnancy.	6 months postpartum

Secondary Outcome Measures

Name	Time	Method
Measurement of cytokine levels and T-cell subsets in maternal blood after Tdap vaccination at different timings in pregnancy.	6 months postpartum
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	At delivery
Measurement of antibody levels, subclass antibody levels, antibody glycosylation and antibody functionality in breastmilk after Tdap vaccination at different timings in pregnancy.	6 months postpartum

Trial Locations

Locations (1)

Vaccinopolis; 🇧🇪 Edegem, Antwerp, Belgium