NCT06881953

Brief Summary

Bronchiolitis is a viral lower respiratory tract infection, caused in 50 to 80% of cases by the respiratory syncytial virus (RSV). Although generally mild, RSV bronchiolitis remains the leading cause of infant hospitalizations for acute respiratory distress in Europe. In France, nearly 30% of children under two years of age are affected annually, representing approximately 480,000 cases. RSV bronchiolitis accounts for 2 to 3% of hospital admissions among infants under one year each winter. These situations place a significant burden on pediatric intensive care units and emergency departments, impacting the delivery of care for other pediatric patients and raising concerns among parent and families. Until September 2023, RSV lower respiratory tract infection prevention strategies in infants in France were limited to non-pharmacological barrier measures, with a monthly injection of the monoclonal antibody palivizumab (Synagis®) recommended among high-risk infants, particularly those born preterm before 35 weeks of gestation. At the end of 2023, a new monoclonal antibody, nirsevimab (Beyfortus®), indicated for passive immunization in the general infant population, received marketing authorization. Administered as a single dose to neonates (from birth) and infants during their first RSV season, nirsevimab demonstrated an estimated efficacy of 76% to 83% in preventing severe RSV bronchiolitis during the 2023-2024 epidemic in France. At the same time, the RSV vaccine Abrysvo® (Pfizer) became available in France since September 2024, following European marketing authorization in August 2023. Administered during the third trimester of pregnancy, this maternal immunization strategy aims to confer passive immunity to neonates (from birth up to six months of age) through transplacental transfer of RSV-specific maternal antibodies. For the 2024-2025 RSV season, the national prevention strategy for RSV-related respiratory infections in infants is based on general non-pharmacological measures and, between September 15, 2024, and January 31, 2025, on maternal vaccination (administered between 32 and 36 weeks of gestation) and/or direct administration of nirsevimab to neonates. To date, no population-based data are available in France regarding maternal adherence to the current RSV prevention strategy for respiratory syncytial virus (RSV) infections in infants. The acceptability of maternal RSV vaccination remains unknown, as well as the factors associated with the choice between the two recommended strategies and the reasons given by pregnant women for their decision. The objective of this study is to assess, in population, the adherence of pregnant women to the current RSV infection prevention strategy for infants in France, which has not yet been studied. The study will focus on the method most commonly chosen by women (maternal vaccination with Abrysvo® during pregnancy or administration of nirsevimab (Beyfortus®) to their neonates), aiming to identify the factors associated with the choice of one strategy over the other and to describe the main reasons women give for their decision to either follow or not follow one of the prevention strategies.

Trial Health

57
Monitor

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Trial has exceeded expected completion date
Enrollment
400

participants targeted

Target at P75+ for all trials

Timeline
Completed

Started Jun 2025

Shorter than P25 for all trials

Geographic Reach
1 country

1 active site

Status
recruiting

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

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Study Timeline

Key milestones and dates

First Submitted

Initial submission to the registry

March 11, 2025

Completed
7 days until next milestone

First Posted

Study publicly available on registry

March 18, 2025

Completed
3 months until next milestone

Study Start

First participant enrolled

June 17, 2025

Completed
6 months until next milestone

Primary Completion

Last participant's last visit for primary outcome

December 17, 2025

Completed
Same day until next milestone

Study Completion

Last participant's last visit for all outcomes

December 17, 2025

Completed
Last Updated

June 24, 2025

Status Verified

March 1, 2025

Enrollment Period

6 months

First QC Date

March 11, 2025

Last Update Submit

June 18, 2025

Conditions

Keywords

Respiratory syncytial virusnirsevimabvaccinehealth campaign

Outcome Measures

Primary Outcomes (1)

  • Adherence of pregnant women to the current RSV infection prevention strategy for infants in France.

    The primary aim of this study is to assess the adherence of pregnant women to the current RSV infection prevention strategy for infants in France, defined as the administration of the RSV vaccine Abrysvo® during pregnancy and/or the direct administration of specific monoclonal antibodies (nirsevimab, Beyfortus®) to the neonate.

    Through study time period, 6 months

Secondary Outcomes (3)

  • Assessing the factors associated with overall adherence to this prevention strategy.

    Through study time period, 6 months

  • Identifying and assessing the maternal and organizational factors associated with the choice of maternal vaccination or administration of nirsevimab to the neonate.

    Through study time period, 6 months

  • Describing the main reasons reported by women to explain their decision to follow or not follow one of the prevention strategies.

    Through study time period, 6 months

Interventions

The questionnaire will be completed on line by the participants (approx. 10 min).

Eligibility Criteria

Age18 Years+
Sexfemale(Gender-based eligibility)
Gender Eligibility Detailsas this study is concerned with pregnancy and maternity, only women will be included.
Healthy VolunteersNo
Age GroupsAdult (18-64), Older Adult (65+)
Sampling MethodNon-Probability Sample
Study Population

Women who gave birth at term in metropolitan France between October 1, 2024, and January 31 or February 2025 (i.e., during the first implementation period of the RSV-related lower respiratory infection prevention strategy for infants in metropolitan France)

You may qualify if:

  • Age ≥ 18
  • Able to speak and understand French well enough to read and comprehend the information leaflet and the questionnaire
  • Delivery in metropolitan France between October 1, 2024, and January 31, 2025
  • Live-born child
  • Term-born child (37 weeks of gestation or more)
  • No objection to participating in the study

You may not qualify if:

  • Women under legal protection

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (1)

Public health department, Hôpital Pitié Salpêtrière

Paris, 75013, France

RECRUITING

MeSH Terms

Conditions

Respiratory Syncytial Virus Infections

Interventions

Surveys and Questionnaires

Condition Hierarchy (Ancestors)

Pneumovirus InfectionsParamyxoviridae InfectionsMononegavirales InfectionsRNA Virus InfectionsVirus DiseasesInfections

Intervention Hierarchy (Ancestors)

Data CollectionEpidemiologic MethodsInvestigative TechniquesHealth Care Evaluation MechanismsQuality of Health CareHealth Care Quality, Access, and EvaluationPublic HealthEnvironment and Public Health

Central Study Contacts

Bénédicte COULM, RM,PhD

CONTACT

Study Design

Study Type
observational
Observational Model
COHORT
Time Perspective
PROSPECTIVE
Sponsor Type
OTHER
Responsible Party
SPONSOR

Study Record Dates

First Submitted

March 11, 2025

First Posted

March 18, 2025

Study Start

June 17, 2025

Primary Completion

December 17, 2025

Study Completion

December 17, 2025

Last Updated

June 24, 2025

Record last verified: 2025-03

Data Sharing

IPD Sharing
Will share

Data are available upon reasonable request The procedures carried out with the French data privacy authority (CNIL, Commission nationale de l'informatique et des libertés) do not provide for the transmission of the database, nor do the information and consent documents signed by the patients. Consultation by the editorial board or interested researchers of individual participant data that underlie the results reported in the article after deidentification may nevertheless be considered, subject to prior determination of the terms and conditions of such consultation and in respect for compliance with the applicable regulations.

Shared Documents
STUDY PROTOCOL, ICF
Time Frame
Beginning 3 months and ending 3 years following article publication. Requests out of these time frame can also be submitted to the sponsor
Access Criteria
Researchers who provide a methodologically sound proposal.

Locations