GBS is a major cause of neonatal infection and long-term control depends on the availability of an effective vaccine. A GBS vaccine would reduce the burden of GBS (maternal disease, stillbirths, premature births and infant disease) by protecting both mothers and infants. Several vaccine candidates are currently in development. The traditional pathway to licensure of a new vaccine includes demonstration of efficacy through a classical phase III trial. This is problematic for GBS, as it is a relatively rare disease, making classical phase III trials difficult and expensive to achieve. However, indirect evidence of protection, based on immunologic data, could facilitate licensure, with subsequent confirmation of effectiveness against disease outcomes in post-licensure evaluations.

PREPARE proposes a program of work that ultimately leads to GBS vaccine licensure and implementation

This program of work will:

• Develop a clinical vaccine trial site in a Sub-Saharan setting capable of undertaking phase II-IV trials
• Determine the pregnancy outcome rates in this population in preparation for trials of vaccines in pregnant women
• Define the burden of neonatal, infant and maternal GBS disease in a Sub-Saharan African population
• Estimate the serocorrelates of protection against the major GBS types causing disease in European and African settings
• Conduct two trials of candidate GBS vaccines

We will do this by:

• Undertaking hospital-based surveillance for GBS disease at a single hospital in Uganda and collecting pregnancy outcome data on a cohort of up to 70 000 women;
• Developing a consortium of sites in Malawi, South Africa, Uganda and Europe collecting longitudinal blood samples and develop a Biobank of these samples in Uganda;
• Use validated serological assays developed by consortium partners to measure antibody concentrations associated with protection against GBS disease in mothers and babies from these bio banked samples;
• Partnering with vaccine manufacturers to test two investigational products in HIV positive and negative women. This proposal meets the requirements of the EDCTP call number RIA2018V by accelerating vaccine development and the progress to licensure of suitable GBS vaccines and providing the background data required by policy makers considering the implementation of GBS vaccines in Sub-Saharan Africa.

For more details, please visit www.gbsprepare.org.

October 2019 – September 2024