STudy of Real World vaccinE Effectiveness of maTernal RSVpreF vaccinatiON Against Respiratory Syncytial Virus (RSV) in Hospitalised Infants in Australia (STREETON)

NCT ID: NCT07122661

Last Updated: 2025-11-19

Basic Information

• Recruitment Status: ACTIVE_NOT_RECRUITING
• Total Enrollment: 1 participants
• Study Classification: OBSERVATIONAL
• Study Start Date: 2025-08-11
• Study Completion Date: 2027-04-30

Brief Summary

This Pfizer-sponsored real-world retrospective non-interventional study will be conducted within a research network comprised of independent hospitals across Australia using data collected during routine standard of care clinical encounters available in health records, supplemented with information from the official national immunisation registry, the Australian Immunisation Register. Additional data from accredited pathology laboratories will be included. There will be no active enrollment of study participants, no direct contact with study participants, and no collection of any primary data outside of the standard of care.

This study will use a test negative design to evaluate real-world vaccine effectiveness of RSVpreF vaccination during pregnancy against RSV-associated outcomes in infants.

Detailed Description

This case-control study using a test negative design will include all infants through 12 months of age who were admitted to one of the participating hospitals with symptoms of respiratory infection, met the clinical case definition of acute respiratory illness, and had a respiratory specimen collected within 10 days prior to hospital admission through 3 days after a hospital admission with an RSV test result through standard of care testing.

The primary objective is to estimate vaccine effectiveness (VE) of ABRYSVO during pregnancy against RSV-positive lower respiratory tract disease (LRTD) hospitalisation among infants from birth through 6 months (0 to ≤180 days) of age.

Baseline characteristics of the study population will be described by case/control status and by maternal RSVpreF vaccination status. Standardised mean differences may be used to compare the distributions (absolute differences >0.10 will be considered meaningful). For all VE objectives, we will use a logistic regression model to compare the odds of maternal ABRYSVO vaccination during pregnancy between test-positive cases and test-negative controls, generating an odds ratio (OR) and 95% CI and we will use multivariable logistic regression to compute an adjusted OR (aOR), from which we will derive final VE estimates, adjusted for potential confounding, according to the formula: VE = (1-aOR) x 100%.

Conditions

Respiratory Syncytial Virus (RSV); Respiratory Syncytial Virus; Lower Respiratory Tract Disease; Respiratory Tract Diseases; Acute Respiratory Illness (ARI)

Study Design

• Observational Model Type: CASE_CONTROL
• Study Time Perspective: RETROSPECTIVE

Study Groups

Cases

Infants who meet the respiratory clinical case definition and test positive for RSV (result obtained from standard of care testing with specimen collected within 10 days prior to hospital admission through 3 days after a hospital admission).

ABRYSVO

Intervention Type: BIOLOGICAL

This is a non-interventional retrospective study; therefore, ABRYSVO vaccine has already been administered according to the standard of care. ABRYSVO is a bivalent RSV prefusion F protein-based vaccine (RSVpreF) composed of two prefusion F proteins to protect against both RSV-A and RSV-B.

Controls

Infants who meet the respiratory clinical case definition and test negative for RSV (result obtained from standard of care testing with specimen collected within 10 days prior to hospital admission through 3 days after a hospital admission).

ABRYSVO

Intervention Type: BIOLOGICAL

This is a non-interventional retrospective study; therefore, ABRYSVO vaccine has already been administered according to the standard of care. ABRYSVO is a bivalent RSV prefusion F protein-based vaccine (RSVpreF) composed of two prefusion F proteins to protect against both RSV-A and RSV-B.

Interventions

ABRYSVO

This is a non-interventional retrospective study; therefore, ABRYSVO vaccine has already been administered according to the standard of care. ABRYSVO is a bivalent RSV prefusion F protein-based vaccine (RSVpreF) composed of two prefusion F proteins to protect against both RSV-A and RSV-B.

Intervention Type: BIOLOGICAL

Other Intervention Names

RSVpreF; RSV Prefusion F

Eligibility Criteria

Inclusion Criteria

1. Infant ≤12 months (≤360 days) of age on the hospitalisation date.

2. Index date within the time period for data collection (approximately 01 March 2025 - 28 February 2027)

3. Hospitalised with acute respiratory illness meeting the protocol-defined clinical case definition, and for whom RSV testing results from a specimen collected 10 days prior to hospital admission through 3 days after a hospital admission are known.

4. Infant born to a birth mother eligible to receive ABRYSVO vaccination, with infant date of birth on or after 17 February 2025.

Exclusion Criteria

Participants meeting any of the following criteria will not be included in the study:

1. Infant born at <28 weeks and 0/7 days of gestational age.

2. Infant received any licensed or investigational RSV preventive product (e.g., palivizumab, nirsevimab, active RSV vaccine) since birth.

3. Infant received ≥1 blood transfusion or other blood products containing antibody (e.g., fresh frozen plasma) since birth.

4. Infant born to a birth mother who received any other licensed or investigational RSV vaccine during this pregnancy.

5. Infant born to a birth mother for whom ABRYSVO vaccination status cannot be confirmed in available data sources.

• Minimum Eligible Age: 0 Years
• Maximum Eligible Age: 12 Months
• Eligible Sex: ALL
• Accepts Healthy Volunteers: No

Sponsors

The Kids Research Institute Australia on behalf of the Centre for Child Health Research, University of Western Australia

UNKNOWN

Sponsor Role: collaborator

Pfizer

INDUSTRY

Sponsor Role: lead

Responsible Party

Responsibility Role: SPONSOR

Principal Investigators

Pfizer CT.gov Call Center

Role: STUDY_DIRECTOR

Pfizer

Locations

Pfizer

Sydney, , Australia

Countries

Australia

Other Identifiers

C3671066

Identifier Type: -

Identifier Source: org_study_id