ClinicalTrials.gg
RecruitingNCT04732026Updated Oct 26, 2023

Serocorrelate of Protection Against GBS (PREPARE WP3)

An observational study in Group B Streptococcus Carrier in Childbirth, Group B Streptococcal Infection, Late-Onset and Group B Streptococcal Infection, Early-Onset, sponsored by St George's, University of London. Recruiting at 6 sites in 6 countries. Open to participants aged Up to 90 Days. Per ClinicalTrials.gov, last updated 2023-10-26.

Sponsored by St George's, University of London · Observational

From the registry’s dates

  • Primary completion was expected by Mar 2024, 2 years 8 months ago, but the record still lists the study as recruiting.
  • Started Apr 2020; still recruiting 6 years 7 months later.
Study type
Observational
Model
Case-control
Time perspective
Prospective
Enrollment
600
Ages
Up to 90 Days
Sex
All
01

Study summary

A multicentre, international case-control study to develop a biobank of sera from 150 cases of serotype III GBS disease and associated clinical information from seven countries (Malawi, Uganda, UK, the Netherlands, Italy and France), with 3:1 (450) serotype matched healthy controls.

Read the detailed description

Group B Streptococcus (GBS) causes severe infections in young infants across the world. In 2015 it was estimated that there were at least 319,000 infants under three months of age with GBS disease worldwide, resulting in 90,000 deaths and at least 10,000 children with long term disabilities. Around 20% of all pregnant women carry GBS in their vagina and bowel, and babies are exposed to GBS bacteria around the time of birth. The options for prevention are currently limited to offering antibiotics during labour.

A vaccine that could be given to pregnant women has the greatest potential to benefit mothers and babies worldwide. There are vaccines currently being tested in clinical trials, including in pregnant women. Given the complexity, size and costs associated with a phase III trial, it is generally agreed that indirect evidence (correlates) of protection (CoP), based on immunologic data from vaccine and seroepidemiological studies, opsonophagocytic assays and supported by animal models, could be pivotal for vaccine licensure, with effectiveness subsequently confirmed in post-licensure evaluations.

This study aims to develop a biobank of sera from 150 cases of serotype III GBS disease and associated clinical information from seven countries (Malawi, Uganda, UK, the Netherlands, Italy and France) with 3:1 (450) serotype matched healthy controls.

GBS cases will be identified through active surveillance of GBS disease in infants, as part of ongoing epidemiological studies in Uganda, the UK, Italy, France, the Netherlands and Malawi. Upon identification of cases, consent will be requested to obtain a serum sample (1-2 mL of blood collected from infant), the GBS isolate and to collect brief clinical and demographic details. Each site will aim to collect around 50 cases of invasive GBS disease cases (with all samples) over the course of 2 years.

Each site will also recruit approximately 1000 women to have a rectovaginal swab at 35-37 weeks gestation and cord and maternal blood samples at delivery. These women and their infants will be followed up to 90 days of age and considered appropriate controls if the infants are exposed to the same serotype/strain of GBS at delivery as the case - but do not develop GBS the first 90 days of life. We will select 3 controls for every case.

The biorepository will be established at the St George's University of London for all samples from the European Union and Malawi and the MRC/UVRI \& LSHTM Uganda Research Unit for Ugandan samples.

02

Conditions studied

  • Group B Streptococcus Carrier in Childbirth
  • Group B Streptococcal Infection, Late-Onset
  • Group B Streptococcal Infection, Early-Onset
  • Group B Streptococcus Neonatal Sepsis
  • Group B Strep Infection
03

In context

Streptococcal Infections

146 studies on the registry are indexed under Streptococcal Infections; 14 are open to participants now.

This study's planned enrollment of 600 is above the median of 400 across 31 observational studies indexed under Streptococcal Infections.

Browse Streptococcal Infections studies →

Lead sponsor

St George's, University of London is the lead sponsor of 106 studies on the registry; 12 are open to participants now.

Counted across the registry records on this site, refreshed daily.

04

Who can participate

Ages eligible
Up to 90 Days
Sexes eligible
All
Sampling method
Non-probability sample

Study population

The study will enroll infant subjects from the general population who are delivered at one of the six hospital sites.

Eligibility criteria

Inclusion Criteria:

Cases:

Infant 0-90 days of life with GBS identified from a normally sterile site.

Controls:

Healthy infant born to a GBS colonised woman that does not develop GBS disease between birth and 90 days of life.

Exclusion Criteria An infant is not eligible unless a parent/person with parental responsibility gives .

Terms in these criteria, in plain language(1)

Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.

Informed consent

Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.

You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.

05

Study design

Observational model
Case-control
Time perspective
Prospective
Enrollment
600 participants (estimated)
Patient registry
No
Biospecimen retention
Samples without dna

Groups and cohorts

  • Cases

    150 infants with invasive serotype III GBS disease (isolation of GBS from a normally sterile site, i.e. blood or CSF) in the first 90 days of life from six countries (Malawi, Uganda, UK, the Netherlands, Italy and France).

  • Controls

    450 infants exposed to serotype III GBS at birth - but who do not develop invasive GBS disease in the first 90 days of life from six countries (Malawi, Uganda, UK, the Netherlands, Italy and France).

06

What researchers measure

Primary outcomes

  1. To establish a biobank of at least 150 GBS serotype III cases including both the isolate and associated maternal and infant serum.

    Biobank at St George's, University of London

    Time frame: Over the course of 2 years

Secondary outcomes

  1. To determine the quantity of antibody associated with protection against GBS disease

    Geometric mean and median antibody titres will be calculated for cases and controls and comparisons made as appropriate

    Time frame: Over the course of 2 years

  2. To determine the functional antibody associated with protection against GBS disease.

    Samples will be tested using opsonophagocytosis killing assay for both anti-capsular and anti-protein antibodies.

    Time frame: Over the course of 2 years

  3. To demonstrate the relationship between antibody quantity and function in protection against GBS disease

    To directly compare total antibody concentration titers (measured by multiplex LUMINEX) with opsonophagocytosis from functional antibodies at the time of birth and at the time of disease.

    Time frame: Over the course of 2 years

  4. To refine estimates for serocorrelates of protection against GBS disease.

    To provide initial data on the relationship between antibody and invasive GBS disease risk by estimating the odds ratio of invasive GBS disease for antibody concentrations above various thresholds for STIII

    Time frame: Over the course of 2 years

  5. To provide training to participating African laboratories to assure the quality of sample collection and data curation.

    A South-South partnership between Makerere University John Hopkins Research Collaboration (MUJHU),and Malawi-Liverpool-Wellcome Trust Clinical Research Programme (MLW) to optimise the capacity for conducting clinical trials for maternal immunisation in Sub-Saharan Africa

    Time frame: Over the course of 2 years

07

Study locations

6 of 6 sites recruiting
08

References and documents

Individual participant data

Plan to share: No

No publications or documents are linked to this record.

09

Timeline

Tracking since Sep 25, 2026
ElapsedEstimatedEstimated, not yet reached

Started Apr 2020 (actual). Primary completion is estimated for Mar 2024, 47 months after the start.

How these figures are worked out, and which studies are left out of them.

Registered
Jan 26, 2021
First posted
Feb 1, 2021
StartActual
Apr 1, 2020
Primary completionEst.
Mar 1, 2024
CompletionEst.
Apr 1, 2024
Last update
Oct 26, 2023
What these dates mean
Start.
When the first participant enrolled; while estimated, when the study expects to open to recruitment.
Primary completion.
When the last participant was examined or treated to collect data for the study's main question, its primary outcome. A study that stopped early gives the date its data collection stopped.
Completion.
When the last participant's last visit took place, for every outcome, secondary ones and side effects included: the end of the study. Often later than primary completion, sometimes the same day.
Actual and Est.
Actual means the registry says the date has happened. Est. (estimated) is a date the sponsor plans or expects. It can still move, and the sponsor is expected to change it to actual once it has passed.
No changes since tracking began. The registry record was last updated on Oct 26, 2023, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
10

Registry details

Key details

Study ID
NCT04732026
Collaborators
MU-JHU CARE, MRC/UVRI and LSHTM Uganda Research Unit, University of Liverpool, Assistance Publique - Hôpitaux de Paris, Academisch Medisch Centrum - Universiteit van Amsterdam (AMC-UvA), Azienda Ospedaliero-Universitaria di Modena
Responsible party
Sponsor
First posted
Feb 1, 2021
Start date
Apr 1, 2020
Primary completion
Mar 1, 2024 (estimated)
Completion
Apr 1, 2024 (estimated)
Last update
Oct 26, 2023

Study contacts

Hannah Davies, Dr
Contact
hdavies@sgul.ac.uk
+442087255214
Madeleine Cochet
Contact
mcochet@sgul.ac.uk
+442087255214
Kirsty Le Doare, Prof
principal investigator · St George's, University of London
Stephen Cose, Dr
principal investigator · London School of Hygiene and Tropical Medicine

Oversight

FDA-regulated drug
No
FDA-regulated device
No
View the source record on ClinicalTrials.gov ↗

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