Group B Streptococcus (GBS) is a leading cause of neonatal infection in Europe and is increasingly recognised as a major cause of neonatal infection in Sub-Saharan Africa1-3. Long-term control depends on the availability of an effective vaccine and is a priority of global health. A GBS vaccine would reduce the burden of GBS (maternal disease, stillbirths, premature births and infant disease including pneumonia, sepsis and meningitis) by protecting both mothers and infants. There are vaccine candidates currently in development, but there are several factors that complicate the licensure process in the context of GBS. The traditional pathway to licensure of a new vaccine includes a classical phase III trial to demonstrate efficacy. As GBS is a relatively rare disease, classical phase III trials are difficult and expensive to achieve. Additionally, the epidemiological data needed to estimate GBS disease burden, and the potential impact of vaccination is lacking in many African countries.

Indirect evidence of protection in the form of immunologic data could facilitate licensure in place of demonstration of efficacy via traditional phase III trials, with post-licensure evaluations providing confirmation of effectiveness against disease outcomes.

The PREPARE project was a multi-country, multi-partner research initiative implemented over 70 months from october 2019 to July 2025. It was designed to generate high-quality scientific data to inform the development and deployment of Group B Streptococcus (GBS) vaccines in Sub-Saharan Africa. The project consisted of six coordinated work packages (WPs), each targeting a different but complementary aspect of the project’s aims. The project was led by city St George’s, University of London (previously St George’s, University of London), and brought together Industry partners with academic institutions in Malawi, South Africa, Uganda, France, Italy, the Netherlands and the UK.

The objectives of PREPARE were to:

· 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.

These overarching objectives were achieved through six work packages (WPs):

· WP1 – Project Management, Scientific Coordination and Oversight of Capacity Building

· WP2 – Clinical trial site development and GBS disease surveillance

· WP3 – Developing serocorrelates of protection against GBS.

· WP4 – Multivalent CPS-conjugate vaccine trial with Pfizer

· WP5 – Minervax Alp-NN GBS vaccine trial

· WP6 – Communications, networking and dissemination

The outputs of PREPARE are being actively exploited in the following ways:

EMR system in Uganda:

Plans to be adopted by Ministry of Health and scaled to other hospitals.

Trial Results:

To be used by Pfizer and MinervaX to support Phase III trial planning.

Biobank and serocorrelate data:

To compare and integrate with other sero-epidemiological studies to define protective thresholds against iGBS, providing the evidence needed by regulatory authorities to support GBS vaccine licensure.

Cohort surveillance data:

Supports public health policy and vaccine prioritisation in Africa.

Capacity strengthening:

Establishes local readiness for future vaccine research and rollout.

The PREPARE project has not only contributed to scientific and medical advancements but has also had a profound effect on the health systems, communities, and researchers it engaged with. The integration of innovative data management tools, extensive vaccine trials, and a collaborative approach between African and European institutions has set a new standard for maternal vaccine research in low-resource settings. The evidence generated will shape global GBS vaccine policy, and the biobank and data repositories will serve as valuable resources for ongoing research. Moreover, the project has demonstrated the power of international collaboration in addressing urgent global health challenges, highlighting how cross-continental partnerships can bridge gaps in knowledge and bring about lasting changes. As the world continues to grapple with the challenges of infectious diseases and vaccine-preventable mortality, the results and lessons learned from PREPARE will continue to influence public health practice, maternal health policy, and global vaccine development for years to come. The legacy of PREPARE lives on in its contributions to vaccine science, maternal health research, and the empowerment of local healthcare systems in Africa, positioning the region to face future health challenges more resiliently. Public Dissemination and Website. PREPARE maintains a public-facing project website that provides a comprehensive view of the project’s objectives, ongoing research, clinical trials, data dissemination, and community engagement efforts. It serves as a key resource for stakeholders, researchers, policymakers, and the public, providing open access to the findings and publications resulting from this groundbreaking initiative. For more detailed information on the PREPARE project, its research findings, and public health initiatives, you can visit the official project website.

Website: www.gbsprepare.org

October 2019 – July 2025